Hurricane Ike and the Turtle September 6, 2008

for a more recent update on hurricane ike, CLICK HERE

Louisville Weather: The weekend looks good. Clouds will lurk the first part of Saturday but never fear, the sun will be here. Saturday afternoon, partly cloudy with highs in the upper 70′s and low 80′s. Sunday, plenty of sunshine, highs in the mid 80′s. Expected big cool-down doesn’t get here until next weekend.

Tropical Storm Hanna Forecast Track 0905 11pm

Tropical Storm Hanna is behaving itself and should remain as a tropical storm as it moves inland near Myrtle Beach, head to Dover Delaware and then to Boston. Its will move very fast and be leaving the coast of Maine by Sunday evening. For a Tropical Storm Hanna Radar Loop, CLICK HERE. Navigate to street level, add clouds and lightning. Hit “animate” to loop the image. It’s not pixelie so knock yourself out. Inland flooding should be limited due to its rapid speed. I would think that one of the biggest threats would be tornadoes and it will be interesting to see what the seas do off of New England.

Hurricane Ike Forecast Track 0906 11pm

Hurricane Ike: I went to a movie premiere tonight on which Snow White did the make-up work. On the one hand, I was surprised when I looked at the models but then again, I wasn’t. See, I told you on Wednesday that we had been expecting a big front here in the Ohio Valley on Tuesday. Its not too unusual when you get into the seasonal change that the models have the general story right but has the timing wrong. In this case, we still have decidedly cooler air coming down the pike, but it won’t be until next weekend. Cold air wants to dive into the US but other features come along that holds it up until it’s allowed to come down. That usually just makes for an adjustment of the long term forecast. In this case, it throws the hurricane forecast into a real stir. Several days ago, the story was for Ike to run across Cuba or south of Florida and

Hurricane Ike Spaghetti Model 0906 00Z

into the Gulf. Then the hurricane models picked up on the front coming through here. If we get a front here that drops our overnight lows into the 40′s, then one would accept the idea that it will go pretty deep and generally quickly, so it made some sense for a number of the models to turn the storm as it was approaching, or before, it got to Florida. Well, now that the models have been keeping the cold air bottled up and, therefore, no trofs digging south, the advertised notion is that the ridge hangs tough or even builds west. So, instead of turning the storm, a the majority of the models are back to taking Hurricane Ike south of the Florida Peninsula and into the Gulf.

Hurricane Ike Spaghetti Model Intensity Graph 0906 00Z

After that…it gets murky. For instance. The 18Z GFS took the storm around the

Hurricane Ike Intensity Probability Table 0905 11pm

Florida peninsula and wrapped it back to landfall between Tampa and Tallahassee. Now, the 00Z GFS takes it across Cuba and heads it west across the Gulf of Mexico and has it hang around in the Central Gulf before taking it toward the central Louisiana coast in about 6 days. That is reasonably close what the 12Z ECMWF does, though its a more direct and slightly quicker route to south Louisiana. Both of these time frames reflect getting caught up by the trof that should be moving through Louisville on Friday night. If you buy the deep digging trof notion, then they both make sense. On the hurricane spaghetti model, you will note some variation of that theme, except that a number of the models have the turn around into the Gulf more in the eastern Gulf. Thats the bad news. The good news is that the longer a storm is alive, the more things that can happen to it to weaken it. In this case, Cuba could pose a problem for Ike. Typically, if a big bopper gets ripped up, it rarely returns to its former intensity. Having said all of that, the National Hurricane Center’s track has a minimal influence from Cuba and advertises a very strong hurricane in the Gulf of Mexico by Day 5. Interests from South Florida to the Gulf states should keep up with this next week. Even South Texas…I mean..what if the hurricane is so far south it sneaks under the trof?

On This Date In History: The United States staged the first submarine attack in history. Well, it was really still the American colonies and it wasn’t a true submarine. It was around midnight in 1776 on September 6 that the British Fleet lay in anchor near Manhattan poised to pounce on General Washington’s beleagured army. Quietly, Sgt. Ezra Lee peddled, with both hands and feet, briskly to turn the propeller of an egg shaped, wooden capsule that was able to float just under the water line using water ballast tanks. The contraption was the brainchild of David Buschnell, who just 4 years before spent his inheritance on an undergraduate degree at Yale. He was, what was then considered, the ripe old age of 30. Buschnell was able to demonstrate that gun powder could be ignited underwater if it were in a close container. So, Lee was to sneak up on the Flag Ship of the British Navy and use a device to screw in a container of gunpowder, ignite it and peddle away as fast as he could. Trouble was, Lee was unable to successfully screw in the charge.

While Buschnell had successfully tested the submarine in the Connecticut River, the currents of the merging East River and Hudson River create a rather turbulent situation when one considers there is the ocean tide tossed in for good measure. It is suspected that Lee was very inexperienced at operating the Turtle and was unable to maintain a stable platform while submerged under the ship. He therefore failed in is two attempts to bore through the hull. He abandoned the mission and released the 130 pound charge after a couple of British rowboats spotted him. While this attempt failed, the whole exercise got the military minds whizzing. It is interesting to note that the Submarine was first conceived as a military weapon, though Jules Verne captured even more imaginative uses with his 20,000 Leagues Under the Sea in the 19th Century.

HURRICANE IKE DISCUSSION NUMBER 20

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008

1100 PM EDT FRI SEP 05 2008

THE EYE OF IKE BRIEFLY RE-APPEARED AROUND 0000 UTC. SINCE THAT TIME AN INTERMITTENT WARM SPOT HAS BEEN SEEN IN THE CENTRAL DENSE OVERCAST IN CONVENTIONAL SATELLITE IMAGERY. THE LATEST MICROWAVE IMAGERY FROM JUST PRIOR TO 0000 UTC INDICATED THAT THE EYE HAD A SMALL OPENING IN THE NORTHWESTERN QUADRANT…OTHERWISE THE INNER-CORE REMAINS WELL INTACT. SUBJECTIVE AND OBJECTIVE DVORAK INTENSITY ESTIMATES ARE BETWEEN T5.5 AND 6.0…AND THE ADVISORY INTENSITY WILL REMAIN 100 KT…OR AT THE LOWER END OF THOSE ESTIMATES. ANOTHER AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT IS SCHEDULED TO INVESTIGATE IKE AROUND 0600 UTC…WHICH SHOULD PROVIDE A MORE ACCURATE ASSESSMENT OF IKE’S STRENGTH. IKE CONTINUES TO MOVE BRISKLY WEST-SOUTHWESTWARD AT ABOUT 14 KT. IKE IS BEING STEERED IN THAT DIRECTION DUE TO A MID-LEVEL RIDGE THAT EXTENDS FROM NEAR BERMUDA SOUTHWESTWARD BETWEEN IKE AND HANNA. THIS RIDGE IS FORECAST TO GRADUALLY SHIFT NORTHWARD DURING THE NEXT COUPLE OF DAYS. AS THIS HAPPENS…IKE IS EXPECTED TO GRADUALLY TURN MORE WESTWARD. THE TRACK GUIDANCE HAS COME INTO BETTER AGREEMENT ON THIS SOLUTION…AND HAS ONCE AGAIN SHIFTED SOUTH AND WESTWARD. IN FACT…MOST OF THE RELIABLE GUIDANCE NOW TAKES HANNA EITHER OVER OR ALONG THE NORTH COAST OF CUBA. THE NEW TRACK HAS BEEN SHIFTED SOUTH AND WESTWARD OF THE PREVIOUS ADVISORY…AND IT IS ALSO A LITTLE FASTER. IT SHOULD BE NOTED…THAT THE DYNAMICAL MODEL CONSENSUS AND SEVERAL OF THE INDIVIDUAL MODELS ARE SOUTHWEST OF THE 4 AND 5 DAY NHC POSITIONS AND IF THIS TREND CONTINUES SOME ADDITIONAL WESTWARD SHIFT COULD BE REQUIRED. THE NORTHEASTERLY SHEAR CURRENTLY DISRUPTING THE HURRICANE IS FORECAST TO ABATE DURING THE NEXT 12 TO 24 HOURS. SINCE IKE…STILL APPEARS TO BE A VERY HEALTHY HURRICANE…LITTLE IF ANY ADDITIONAL WEAKENING IS EXPECTED BEFORE IT REACHES THE SOUTHEASTERN BAHAMAS. BEYOND 36 HOURS…THE SHEAR IS FORECAST TO BE VERY LIGHT AND THE ONLY NEGATIVE FACTOR FOR STRENGTHENING WILL BE POSSIBLE LAND INTERACTION. WITH THE OFFICIAL TRACK PREDICTION ALONG THE NORTHERN COAST OF CUBA…IT SHOWS ONLY SLIGHT WEAKENING DUE TO LAND. HOWEVER…IKE COULD BE WEAKER THAN SHOWN BELOW IF THE CENTER MOVES OVER CUBA…AND CONVERSELY COULD BE A LITTLE STRONGER IF IT REMAINS OVER WATER.

FORECAST POSITIONS AND MAX WINDS

INITIAL 06/0300Z 22.6N 65.6W 100 KT

12HR VT 06/1200Z 22.3N 67.6W 100 KT

24HR VT 07/0000Z 22.0N 70.3W 100 KT

36HR VT 07/1200Z 21.9N 72.8W 105 KT

48HR VT 08/0000Z 21.9N 75.3W 115 KT

72HR VT 09/0000Z 22.9N 79.6W 110 KT

96HR VT 10/0000Z 24.5N 82.5W 110 KT

120HR VT 11/0000Z 26.0N 84.5W 115 KT

$$ FORECASTER BROWN/AVILA

Hurricane Ike, Tropical Storm Hanna-Steady As She Goes September 5, 2008

Hurricane Ike 0905 2115Z

for a more recent update on hurricane Ike, click here

Hurricane Ike Forecast Track 0905 5pm

There’s really nothing new to report regarding Hurricane Ike or Tropical Storm Hanna. You can find a Tropical Storm Hanna Radar Loop by a simple CLICK HERE. It’s close enough to radar installations to get a good look. Just navigate from the default area of the Ohio Valley to the coast. You can get lightning, clouds and radar all the way to street level so if you have friends in, say Wilmington, you can see what’s happening at their house.

Otherwise, I’m letting the National Hurricane Center Forecast Discussion stand alone this time. Dr. Jack Beven always does a great job. For my take, you can scroll back or Click Here for the previous post.

HURRICANE IKE DISCUSSION NUMBER 19

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008

500 PM EDT FRI SEP 05 2008

Hurricane Ike Spaghetti Model 0905 18Z

AN AIR FORCE RECONNAISSANCE PLANE HAS PERFORMED THE FIRST PENETRATIONS ON IKE AND HAS CONFIRMED THE SATELLITE ESTIMATES. PEAK FLIGHT LEVEL WINDS OF 109 KT WERE RECORDED…ALONG WITH SFMR WINDS OF 94 KT…PLUS A DROPSONDE SUGGESTED WINDS OF AT LEAST 95 KT. A CONSENSUS OF ALL DATA SOURCES SUGGEST SUSTAINED WINDS OF AROUND 100 KT…SO THIS VALUE WILL BE THE INITIAL INTENSITY. SOME WEAKENING COULD OCCUR IN THE NEXT DAY OR SO DUE TO PERSISTENT NORTHERLY SHEAR. HOWEVER THIS SHEAR IS FORECAST TO DIMINISH BY LATE TOMORROW…AND SHOULD ALLOW SOME STRENGTHENING…PERHAPS RAPID…BY LATE IN THE WEEKEND. THE OFFICIAL FORECAST IS BASICALLY AN UPDATE OF THE PREVIOUS ONE…SHOWING AN EXTREMELY DANGEROUS HURRICANE FOR THE NEXT SEVERAL DAYS. THIS FORECAST IS IN LINE WITH LGEM MODEL EARLY ON…AND IS

Hurricane Ike spaghetti model Intensity Graph 0905 18Z

A LITTLE LOWER THAN THE GFDL/HWRF THEREAFTER. A BIG UNCERTAINTY IN THE LONG RANGE INTENSITY FORECAST IS IKE’S POTENTIAL INTERACTION WITH CUBA OR FLORIDA…WHICH COULD WEAKEN THE HURRICANE MORE THAN SHOWN BELOW. AIRCRAFT AND SATELLITE FIXES SUGGEST A MOTION OF ABOUT 255/13. A GRADUAL BEND BACK TOWARD THE WEST IS FORECAST IN A DAY OR SO AS RIDGING TO THE NORTHWEST OF IKE WEAKENS SOMEWHAT. ALL MODELS SUGGEST SOME SORT OF WEAKNESS IN THE RIDGE NEAR FLORIDA IN A FEW DAYS BETWEEN A RIDGE OVER THE WESTERN ATLANTIC AND THE GULF OF MEXICO. THIS WEAKNESS MAY ALLOW A WEST-NORTHWEST OR NORTHWEST TURN OF THE HURRICANE. GENERALLY…THE MODELS THAT ARE SHOWING THE NORTHERNMOST TRACKS…SUCH AS THE GFS/NOGAPS…ARE THE ONES WEAKENING THE RIDGE TO THE NORTH FASTER. THE MODELS WITH THE SOUTHERNMOST TRACKS…SUCH AS THE ECMWF/UKMET/GFDL…SHOW A STRONGER RIDGE. OVERALL…MODELS HAVE SHIFTED A LITTLE TO THE SOUTH…AND I’M GOING TO CONTINUE TO LEAN THE FORECAST IN THAT DIRECTION. IF CURRENT TRENDS PERSIST…THE FORECAST COULD BE SHIFTED FARTHER TO THE SOUTH OR WEST LATER TONIGHT. IT SHOULD BE STRESSED THAT FOUR- AND FIVE-DAY TRACK FORECASTS CAN HAVE SIGNIFICANT ERRORS…AND ONE SHOULD NOT FOCUS ON THE EXACT TRACK.

FORECAST POSITIONS AND MAX WINDS

INITIAL 05/2100Z 22.9N 64.1W 100 KT

12HR VT 06/0600Z 22.6N 66.2W 95 KT

24HR VT 06/1800Z 22.2N 68.9W 95 KT

36HR VT 07/0600Z 22.1N 71.3W 100 KT

48HR VT 07/1800Z 22.2N 73.7W 110 KT

72HR VT 08/1800Z 23.0N 78.2W 115 KT

96HR VT 09/1800Z 24.5N 81.5W 115 KT

120HR VT 10/1800Z 25.5N 83.0W 115 KT

$$ FORECASTER BLAKE/BEVEN

TROPICAL STORM HANNA DISCUSSION NUMBER 36

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082008

500 PM EDT FRI SEP 05 2008

Tropical Storm Hanna Spaghetti Model 0905 18Z

REPORTS FROM AN AIR FORCE RESERVE HURRICANE HURRICANE HUNTER AIRCRAFT

INDICATE THAT HANNA IS JUST BELOW HURRICANE STRENGTH. THE STEPPED

Tropical Storm Hanna Forecast Track 0905 5pm

FREQUENCY MICROWAVE REPORTED TWO AREAS OF WIND OF ABOUT 65 KT. HOWEVER…DROPSONDE DATA SUGGESTS THAT THE SFMR ESTIMATES WERE A LITTLE TOO HIGH. THE MAXIMUM 850 MB FLIGHT-LEVEL WINDS WERE 75 KT ABOUT 75 N MI EAST OF THE CENTER. THE LAST REPORTED CENTRAL PRESSURE WAS 984 MB…UP A LITTLE FROM THIS MORNING. BASED ON ALL THIS…THE INITIAL INTENSITY IS SET AT 60 KT. IT SHOULD BE NOTED THAT THERE IS NOT MUCH DIFFERENCE METEOROLOGICALLY BETWEEN A 60-KT TROPICAL STORM AND A 65-KT HURRICANE. THE MOTION IS A SOMEWHAT WOBBLY 360/17…WITH A RE-ANALYSIS OF AIRCRAFT DATA SUGGESTING THIS MOTION BEGAN JUST AFTER THE 11Z AIRCRAFT FIX. HANNA IS MOVING AROUND THE WESTERN END OF THE SUBTROPICAL RIDGE OVER THE WESTERN ATLANTIC AND SHOULD ENTER THE WESTERLIES IN 24-36 HR. THIS SHOULD RESULT IN RECURVATURE TO THE NORTHEAST AND ACCELERATION. ALL GUIDANCE AGREES WITH THIS SCENARIO…AND THERE ARE NO SIGNIFICANT OUTLIERS AMONGST THE DYNAMICAL MODELS. THE NEW FORECAST TRACK IS ADJUSTED A LITTLE TO THE RIGHT OF THE PREVIOUS TRACK AND LIES DOWN THE MIDDLE OF THE GUIDANCE ENVELOPE. VERTICAL WIND SHEAR AND DRY AIR ENTRAINMENT ARE STILL ISSUES FOR HANNA…AND SIGNIFICANT STRENGTHENING APPEARS UNLIKELY BEFORE LANDFALL. HOWEVER…THERE IS A POSSIBILITY THAT A CONVECTIVE BURST COULD CAUSE THE STORM TO REACH HURRICANE STRENGTH. THE CYCLONE SHOULD WEAKEN AFTER LANDFALL AND BECOME EXTRATROPICAL IN ABOUT 36 HR. THE GFS AND UKMET CONTINUE TO SUGGEST THE POSSIBILITY OF DEEPENING AS AN EXTRATROPICAL SYSTEM LATE IN THE FORECAST PERIOD…AND THIS IS REFLECTED IN THE 96 AND 120 HR FORECASTS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 05/2100Z 30.8N 78.7W 60 KT

12HR VT 06/0600Z 33.2N 78.5W 60 KT

24HR VT 06/1800Z 36.7N 76.8W 50 KT…INLAND

36HR VT 07/0600Z 40.7N 72.4W 45 KT…EXTRATROPICAL

48HR VT 07/1800Z 44.5N 65.6W 40 KT…INLAND EXTRATROPICAL

72HR VT 08/1800Z 50.0N 47.5W 40 KT…EXTRATROPICAL

96HR VT 09/1800Z 51.0N 30.0W 45 KT…EXTRATROPICAL

120HR VT 10/1800Z 52.5N 14.0W 45 KT…EXTRATROPICAL

$$ FORECASTER BEVEN

Hurricane Ike Comparable to Ike Harris? Is Tropical Storm Hanna Part of a “Triple Threat?” September 5, 2008

for a more recent update on Hurricane Ike and Hanna, Click Here

I’m sitting here flipping through the channels and see one cable network continually saying “the east coast is facing a triple threat!”. They say people are “bracing” for Hanna, that Ike is “threatening” and Josephine is coming along like “an angry cousin.” Hrmph. this type of hyperbole is dangerous because it creates the “boy who cried wolf” situation. When it really is serious, as may be the case in a week with Ike, then some people may not listen.

For a Tropical Storm Hanna Radar Loop, CLICK HERE navigate wherever you like, even to street level. Hit “animate” to loop.

Tropical Storm Hanna Forecast Track 0905 11AM

First, we’ll chat a bit about Tropical Storm Hanna and then we’ll get to Hurricane Ike and how it relates to former NFL star Ike Harris. Hanna is a tropical storm that

Tropical Storm Hanna Spaghetti Model 0905 12Z

perhaps has questionable tropical cyclone characteristics but certainly has winds that may be gusting in some quadrants to hurricane force. And, I have to admit that the satellite imagery is looking pretty good all of a sudden. The winds may in fact get to hurricane force but the general effect of the storm will be some coastal tidal flooding and some storms that would have the potential for tornadoes. Okay…winds of 65-75 mph can be an issue but in this case, those

Tropical Storm Hanna Spaghetti Model Intensity Graph 0905 11AM

type of winds will be more of the exception than the rule as the storm is not fully formed. Yes, you hear on TV that its “getting organized” but its got a long way to go to be truly fearsome in that regard and not much ocean to work with. The rainfall flood potential will be limited by its increasing forward speed as it is forecast to be in North Carolina for Saturday morning and 24 hours later be near the Kennedy Compound in Massachusetts. I heard a tv foof just say that “it looks like a washout on the east coast this entire weekend.” Nonsense. But, as the storm zips by, it would not be wise to dismiss it. These guys interacting along the coast seem to enhance the possibility of tornadoes, that can hit and leave very quickly and with little warning. The National Hurricane Center Forecast Discussion for Tropical Storm Hanna is at the bottom.

Hurricane Ike As Successful As Ike Harris In Second Phase of Life?

Hurricane Ike As Tough as Ike Harris(82)?

Hurricane Ike: So far, I have found a way to compare Hurricane Ike to Tina Turner and Ike Clanton. Now, I’ve come up with Ike Harris. Harris was a pro-football player of note with the Cardinals and Saints. He had over 3300 yards receiving and 16 touchdowns. So, what does that have to do with Hurricane Ike aside from their names? Well, being a professional athlete for several years is a pretty high accomplishment. A hurricane reaching Cat 4 status in a short period of time is pretty

impressive as well. Once Ike Harris’ athletic career ending, he used the education he received at Iowa State and as the door of one chapter of his life ended, a new one opened and today, Ike Harris is a respected and successful member of the business community. He was named as one of the top 75 most powerful African-Americans in corporate America. Please read this press release. So often we hear about athletes who don’t do so well when their career is over. We need to hear more about people like Mr. Harris who has no doubt positively influenced numerous lives and probably could do more if the word got out. I just did my part.

Hurricane Ike Forecast Track 0905 11AM

Okay..so how does Ike Harris’ story compare to the tale of Hurricane Ike. Well, the

Hurricane Ike Spaghetti Model Intensity Graph 0905 12Z

first part of Ike’s career is just about done. It was a very strong hurricane but has been chopped a bit by strong northeasterly shear. It has gotten weaker. This often spells the end of tropical cyclones. But, Hurricane Ike will probably begin anew and grow in intensity and most likely, become a geographically larger storm. It’s pretty small now but I’ve observed over the years that small storms don’t usually stay small for long. Hurricane Camille was a small storm with 200 mph winds when it hit Mississippi in 1969, but it had only

Hurricane Ike Spaghetti Model 0905 12Z

been a hurricane for less than 3 days. Ike is moving west, a big fat ridge is building. That building in ridge is part of the reason why Hanna will kicked shot out like a cannon to the northeast because the ridge is building Soutwest behind it

Hurricane Ike Intensity Probability Table 0905 11AM

toward Florida. That ridge will drive the storm southwest toward the Bahamas.

I think I’ve been suggesting that it wasn’t a good idea to totally write off a Gulf of Mexico scenario and at that point, the issue remains iffy but seems to have a bit more clarity. We in Louisville were looking at a strong front coming down early in the week and bringing decidedly cooler air. We have shoved that back to the end of the week because indications are that forces upstream will not allow the cool air to move in so quickly. The big push South, in other words, is being held up. Because the trof associated with the front is going to be delayed, then the erosion of the ridge building into Florida could be delayed. More and more models are going along with that scenario with many returning to an old story of several days ago that wants to take the storm either South of Florida, possibly through Cuba, or across Florida into the Gulf of Mexico. The number of models suggesting a turn prior to the Florida Peninsula has decreased markedly. The official forecast has shifted west, hooking around the southern tip of Florida.

Bottom line: Strong hurricane moving to the Bahamas. Threat to Florida great. Threat to East Coast falling. Threat to Gulf States increasing. Forecast track after 84 hours, very much in flux. Note the last line in the NHC discussion.

HURRICANE IKE DISCUSSION NUMBER 18

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008

1100 AM EDT FRI SEP 05 2008

NORTHERLY SHEAR CONTINUES TO A TAKE A TOLL ON IKE. SATELLITE IMAGES SHOW THAT THE EYE HAS BECOME LESS CLEAR AND THAT MOST OF THE CONVECTION IS IN THE SOUTHERN SEMICIRCLE. IN ADDITION…A RECENT SSMIS MICROWAVE IMAGE SHOWS THAT THE EYEWALL IS OPEN ON THE NORTH SIDE. USING A BLEND OF THE OBJECTIVE AND SUBJECTIVE DVORAK CLASSIFICATIONS…THE INITIAL INTENSITY IS LOWERED TO 105 KT…AND THIS COULD BE GENEROUS. AN AIR FORCE RESERVE RECONNAISSANCE PLANE IS SCHEDULED TO INVESTIGATE THE HURRICANE THIS AFTERNOON TO OBTAIN A BETTER ESTIMATE OF THE CURRENT INTENSITY AND WIND RADII. ALMOST ALL OF THE GLOBAL MODELS SHOW DECREASING SHEAR OVER IKE IN ABOUT A DAY DUE TO A WEAKENING OF STRONG NORTHEASTERLY UPPER WINDS. EXCEPT FOR A SMALL PATCH OF SSTS NEAR AND NORTH OF THE SOUTHEASTERN BAHAMAS…WATERS ARE VERY WARM ALONG THE FORECAST PATH. THE OFFICIAL FORECAST SHOWS A SLOW WEAKENING OF THE HURRICANE DUE TO THE SHEAR FOR THE FIRST 24 HOURS…THEN SHOWS INTENSIFICATION AS UPPER-WINDS SLACKEN…IN GENERAL AGREEMENT WITH THE LGEM MODEL. IN A COUPLE DAYS…VERTICAL WIND SHEAR WILL LIKELY BECOME LIGHT…AND CONDITIONS LOOK RATHER FAVORABLE FOR INTENSIFICATION. THE OFFICIAL FORECAST COULD BE CONSERVATIVE IN THE LONGER-RANGE AS THE HWRF AND GFDL SHOW A MORE INTENSE HURRICANE. REGARDLESS OF EXACTLY HOW STRONG IT IS…ALL SIGNS ARE THAT IKE WILL BE A DANGEROUS HURRICANE FOR DAYS TO COME. IKE HAS BEEN MOVING SOUTH OF WEST DURING THE PAST FEW HOURS…ABOUT 260/14. THIS GENERAL TRACK WITH SOME DECREASE IN FORWARD SPEED IS FORECAST OVER THE NEXT 36 HOURS DUE TO A STRONG RIDGE WEDGING INTO BETWEEN IKE AND HANNA. THE RIDGE SHOULD WEAKEN SOMEWHAT IN A COUPLE OF DAYS…STEERING THE HURRICANE MORE TO THE WEST AND EVENTUALLY WEST-NORTHWEST. HOWEVER…MODELS ARE NOT IN GOOD AGREEMENT ON WHEN THIS WEST-NORTHWEST MOTION COULD MATERIALIZE. GENERALLY THE MODELS THAT DRIVE THE SYSTEM FARTHER SOUTH…SUCH AS THE ECMWF/HWRF/GFDL MODELS…SUGGEST THE RIDGE WILL REMAIN INTACT ENOUGH TO EVENTUALLY SEND IKE TOWARD CUBA OR THE SOUTHEASTERN GULF OF MEXICO. THE UKMET/GFDN/NOGAPS…ON THE OTHER HAND…SUGGEST THE HURRICANE WILL MOVE MORE THE WEST AND HAS A BETTER CHANCE OF BEING AFFECTED BY A WEAKNESS IN THE RIDGE AROUND 80W. SINCE THE HURRICANE IS MOVING WELL SOUTH OF THE LATTER CLUSTER OF MODELS ALREADY…THE OFFICIAL FORECAST LEANS MORE TOWARD THE SOUTHERN GUIDANCE AND SHIFTED SOUTHWEST OF THE PREVIOUS FORECAST. IT CANNOT BE REPEATED ENOUGH THAT FOUR- AND FIVE-DAY TRACK FORECASTS CAN HAVE SIGNIFICANT ERRORS…AND COMBINED WITH THE FACT THAT THE MODEL SPREAD IS STILL NOTABLE BEYOND 72 HOURS…ONE SHOULD NOT FOCUS ON THE EXACT TRACK.

FORECAST POSITIONS AND MAX WINDS

INITIAL 05/1500Z 23.2N 62.7W 105 KT

12HR VT 06/0000Z 22.9N 64.7W 95 KT

24HR VT 06/1200Z 22.5N 67.4W 90 KT

36HR VT 07/0000Z 22.2N 69.9W 95 KT

48HR VT 07/1200Z 22.2N 72.5W 105 KT

72HR VT 08/1200Z 23.0N 77.0W 115 KT

96HR VT 09/1200Z 24.0N 80.0W 115 KT

120HR VT 10/1200Z 25.5N 82.0W 100 KT

$$ FORECASTER BLAKE

WTNT43

KNHC 051452 TCDAT3

TROPICAL STORM HANNA DISCUSSION NUMBER 35

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082008

1100 AM EDT FRI SEP 05 2008

SATELLITE IMAGERY AND RADAR DATA FROM THE MELBOURNE WSR-88D INDICATE THAT HANNA HAS BECOME A LITTLE BETTER ORGANIZED THIS MORNING…AS THE LATEST CONVECTIVE BURST HAS PRODUCED AN INNER WIND CORE. HOWEVER…THE RADAR-OBSERVED VELOCITIES DO NOT YET SUGGEST INTENSIFICATION. THE INITIAL INTENSITY REMAINS 55 KT. THE CENTER OF HANNA JOGGED WESTWARD BETWEEN 06-12Z. HOWEVER…THE MELBOURNE RADAR SUGGEST THE CENTER HAS RESUMED A MORE NORTHWARD MOTIONS…WITH THE INITIAL MOTION ESTIMATED AT 325/17. HANNA IS MOVING AROUND THE WESTERN END OF THE SUBTROPICAL RIDGE OVER THE WESTERN ATLANTIC AND SHOULD ENTER THE WESTERLIES IN 24-48 HR. THIS SHOULD RESULT IN RECURVATURE TO THE NORTHEAST AND ACCELERATION. ALL GUIDANCE AGREES WITH THIS SCENARIO…AND THERE ARE NO SIGNIFICANT OUTLIERS AMONGST THE DYNAMICAL MODELS. THE NEW FORECAST TRACK IS ADJUSTED A LITTLE TO THE LEFT FOR THE FIRST 36 HR TO ACCOUNT FOR THE INITIAL POSITION…AND IS CLOSE TO THE PREVIOUS FORECAST TRACK THEREAFTER. WHILE VERTICAL WIND SHEAR AND DRY AIR ENTRAINMENT ARE STILL ISSUES…THE INCREASED ORGANIZATION SUGGESTS THE POSSIBILITY OF STRENGTHENING BEFORE LANDFALL. THUS…THE INTENSITY FORECAST CALLS FOR A PEAK INTENSITY OF 60 KT NEAR LANDFALL. NONE OF THE GUIDANCE INDICATES THAT HANNA WILL REACH HURRICANE STRENGTH PRIOR TO LANDFALL…ALTHOUGH THIS CANNOT BE RULED OUT. THE CYCLONE SHOULD WEAKEN AFTER LANDFALL AND BECOME EXTRATROPICAL IN ABOUT 48 HR. THE GFS AND UKMET SUGGEST THE POSSIBILITY OF DEEPENING AS AN EXTRATROPICAL SYSTEM LATE IN THE PERIOD…AND THIS IS REFLECTED IN THE 96 AND 120 HR FORECASTS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 05/1500Z 28.9N 79.2W 55 KT

12HR VT 06/0000Z 31.2N 79.7W 60 KT

24HR VT 06/1200Z 34.5N 79.1W 55 KT…INLAND

36HR VT 07/0000Z 38.2N 76.1W 45 KT…INLAND

48HR VT 07/1200Z 42.5N 70.1W 40 KT…EXTRATROPICAL

72HR VT 08/1200Z 49.0N 52.5W 40 KT…EXTRATROPICAL

96HR VT 09/1200Z 50.5N 35.0W 45 KT…EXTRATROPICAL

120HR VT 10/1200Z 51.0N 18.5W 45 KT…EXTRATROPICAL

$$ FORECASTER BEVEN

Hurricane Ike Still Mean; More Like Ike Clanton Than Ike Turner September 4, 2008

for a more recent update on Hurricane Ike, CLICK HERE

For a radar loop of Tropical Storm Hanna as it approaches the US Coast, CLICK HERE. This site allows for navigation to street level and is not clouded by pixels. Keep in mind that radar returns may be sparse until the storm comes in range of US radar installations.

Hurricane Ike Clanton?

Hurricane Ike continues to be quite strong. It seems to have a demeanor more akin to Wyatt Earp nemesis Ike Clanton than Ike Turner. The Ike of Tombstone, AZ fame managed to escape the famed Gunfight at the OK Corral in 1881unscathed. But, he continued his life of crime and violence. After being tracked down by a detective on his trail after charges of cattle-rustling, Ike refused to surrender and was shot and killed by Jonas Brighton on June 1, 1887.

Now, Hurricane Ike is violent and, like Ike Clanton, will get into a bit of a tussle that could threaten its life, but will probably emerge unscathed. Ike will encounter some pretty decent shear that will diminish its intensity as it disrupts the upper outflow. But, Ike is moving right along and should escape the shear and move back into a more favorable environment. Data

Hurricane Ike Forecast Track 0904 5PM

still suggests that a ridge builds in and the storm takes on about a vector of 240 degrees, which is a bit unusual and indicates just how strong the ridge building in

Hurricane Ike Spaghetti Model Intensity Graph 0904 18Z

really is. Because the ridge is so strong, I doubt if the storm will stall, though the forward speed may be reduced as it reaches the periphery of the ridge when it gets to the Bahamas. The National Hurricane Center mentions in their discussion the cold upwelling produced by Hanna’s residency in the Bahamas that I mentioned previously. But, they don’t reach a strong conclusion given that the storm will be moving over very warm water prior to reaching the area of probable upwelling and because the storm is not projected to stall.

I have thought for days that Ike would be a trouble maker and I would think it would be wise of folks in

Hurricane Ike Intensity Probability Table 0904 5PM

Hurricane Ike Spaghetti Model 0904 18Z

Florida to be of the same mind. Earlier the general track took the storm across Cuba or Florida into the Gulf. But, a strong trof associated with a cold front, that might drop our overnight temperatures in the Ohio Valley to the 40′s, will traverse the nation. The last couple of days the models had picked up on this feature and advertised a turn from the Bahamas. It was, and still remains, possible that the storm may get caught up in the trof and turn safely away from the US. There was always the possibility that the trof did not dig down far enough south to pick up the storm. The latest models are trying to inch the outlying track farther west, with one even taking it back to the old crossing-Cuba solution. For that reason, Gulf Coast residents should probably keep their ears on. I can’t imagine a cold front of the stature that I described not digging far enough so south. My limited imagination notwithstanding, there remains the possibility that the ridge between the front and the hurricane may get squished and elongated, but stay in place, thus presenting a more westerly track.

The NHC does not go that far but has shifted the late day track farther west. Given the forecast track, there is a very real possibility that South Florida may be in the way of a very strong hurricane by the middle of next week.

That is not the case this week. Hanna has dry air intrusion, has hung around over the same place for so long that it is killing itself by bringing cold water to the surface. It is in a very bad spot and there is not any data that suggests that Hanna will become a hurricane again. Nevertheless, it is still a threat for strong ripe tides…not a good idea to go surfing. It will bring some rise in tides and bring strong storms with heavy rain and gusty winds along the coast. The landfall with a storm such as this is not overly important, except that the strongest winds will be near what should be a rather broad area of low pressure affecting the Carolinas. Should be a pretty tough day on the Outer Banks and a wet day or so up the Eastern Sea Board. While it will be dangerous, the risk of a catastrophic event is low.

Josephine is still a long way out and I’m not overly concerned nor excited about it at this time. Here is the National Hurricane Center Forecast Discussion for Hurricane Ike followed by the National Hurricane Center Discussion for Tropical Storm Hanna:

HURRICANE IKE DISCUSSION NUMBER 15

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

AL092008 500 PM EDT THU SEP 04 2008

THERE HAS BEEN LITTLE CHANGE TO THE OVERALL APPEARANCE OF IKE DURING THE PAST FEW HOURS. IKE IS MAINTAINING A WELL-DEFINED EYE…THOUGH CLOUD TOPS HAVE WARMED SOME IN THE EYEWALL RECENTLY. IT IS INTERESTING THAT WHILE IKE STARTED OUT AS A LARGE SYSTEM…THE CLOUD CANOPY HAS NOTICEABLY SHRUNK TODAY WITH FEW OUTER BANDS. THERE HAS BEEN ONLY A SMALL DECREASE IN OBJECTIVE T-NUMBERS…SO THE INITIAL INTENSITY IS REDUCED SLIGHTLY TO 115 KT. STRONG NORTHEASTERLY SHEAR IS LIKELY DURING THE NEXT DAY OR SO…WHICH SHOULD CAUSE WEAKENING. IN FACT…THE SHIPS MODEL RESPONDS TO THE SHEAR BY WEAKENING THIS SYSTEM TO A CATEGORY ONE HURRICANE…THOUGH THE GFDL/HWRF ARE CONSIDERABLY HIGHER. IN A COUPLE DAYS…VERTICAL WIND SHEAR IS FORECAST TO WEAKEN AND…COMBINED WITH RATHER WARM WATER WATERS EAST OF THE BAHAMAS…SHOULD RESULT IN RESTRENGTHENING. THE HURRICANE’S EXACT TRACK IS IMPORTANT BECAUSE IT COULD BE IMPACTED BY COOLER WATERS UPWELLED BY HANNA. THE OFFICIAL FORECAST IS CLOSE TO THE PREVIOUS ONE BUT IS A LITTLE LOWER FOR THE FIRST 36 HOURS OUT OF RESPECT FOR THE SHIPS/LGEM MODELS. IKE IS EXPECTED TO BE A POWERFUL HURRICANE AS IT APPROACHES THE BAHAMAS IN A COUPLE OF DAYS. THE INITIAL MOTION ESTIMATE IS 285/12…SLOWER THAN BEFORE AND A LITTLE TO THE LEFT. RIDGING FROM THE CENTRAL ATLANTIC IS FORECAST TO BUILD TO THE NORTH AND NORTHWEST OF THE TROPICAL CYCLONE… CAUSING A WEST…AND THEN WEST-SOUTHWEST MOTION OF IKE BY LATE TOMORROW. THE STRENGTH OF THE RIDGING BETWEEN IKE AND HANNA WILL BE CRITICAL TO WHEN AN EVENTUAL TURN TOWARD THE WEST-NORTHWEST WILL OCCUR IN THE LONG-RANGE. THERE HAS BEEN A NOTICEABLE WESTWARD SHIFT IN ALMOST ALL OF THE GLOBAL MODEL GUIDANCE TODAY…WITH THE GFDL/ECMWF EVEN TAKING THE SYSTEM AS FAR SOUTHWEST AS CUBA. THE OTHER MODELS ARE PRETTY CLUSTERED ON A TRACK NEAR OR THROUGH THE CENTRAL AND NORTHWESTERN BAHAMAS. THE NHC FORECAST IS SHIFTED WESTWARD AND IS PRETTY CLOSE TO THE HWRF MODEL. ONE SHOULD NOT FOCUS ON THE EXACT 4 AND 5 DAY FORECAST POSITIONS BECAUSE LARGE UNCERTAINTIES EXIST AT THOSE TIMES. FORECAST POSITIONS AND MAX WINDS

INITIAL 04/2100Z 23.6N 58.2W 115 KT

12HR VT 05/0600Z 23.9N 60.0W 105 KT

24HR VT 05/1800Z 23.7N 62.5W 95 KT

36HR VT 06/0600Z 23.2N 65.1W 95 KT

48HR VT 06/1800Z 22.7N 67.7W 100 KT

72HR VT 07/1800Z 22.5N 72.5W 105 KT

96HR VT 08/1800Z 24.0N 76.0W 110 KT

120HR VT 09/1800Z 25.5N 79.0W 110 KT

$$ FORECASTER BLAKE

TROPICAL STORM HANNA DISCUSSION NUMBER 32

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

AL082008 500 PM EDT THU SEP 04 2008

THE RECONNAISSANCE AIRCRAFT INVESTIGATING HANNA IS FINDING THE CIRCULATION CENTER AT 850 MB DISPLACED TO THE NORTHWEST OF THE MEAN CENTER OF ROTATION APPARENT IN THE LOW CLOUD LINES. THERE ARE ALSO MULTIPLE SWIRLS…BUT IT DOES APPEAR THAT THE LOW-LEVEL CENTER HAS JUMPED A LITTLE BIT TO THE WEST IN RESPONSE TO THE CONVECTIVE ASYMMETRY. ALTHOUGH A COUPLE MORE SHIFTS ARE POSSIBLE…THE ORIENTATION OF THE SHEAR SHOULD TURN MORE SOUTHERLY WITH TIME…THAT IS…MORE ALONG THE TRACK…AND THEN HAVE LESS OF AN IMPACT ON THE TRACK. THE BASIC FORECAST PHILOSOPHY IS UNCHANGED. THE NEW TRACK FORECAST IS VERY CLOSE TO THE PREVIOUS ONE WITH ONLY A SLIGHT LEFTWARD SHIFT…AND IS NEAR THE MODEL CONSENSUS. RECONNAISSANCE DATA THUS FAR DO NOT SUPPORT ANY INCREASE IN THE INTENSITY ESTIMATE. WATER VAPOR IMAGERY CONTINUES TO SHOW VERY DRY AIR IMPINGING ON HANNA FROM THE SOUTHEAST…AND THIS IS EXPECTED TO CONTINUE. WHILE THE VERTICAL SHEAR IS FORECAST TO DIMINISH A LITTLE PRIOR TO LANDFALL…NONE OF THE OBJECTIVE GUIDANCE MODELS NOW MAKE HANNA A HURRICANE AND THE OFFICIAL INTENSITY FORECAST NOW TOPS OUT AT 60 KT. HURRICANE WATCHES WILL REMAIN IN EFFECT FOR THE POSSIBILITY THAT HANNA BECOMES A LITTLE STRONGER THAN FORECAST…AND PEOPLE ARE REMINDED THAT THERE IS VERY LITTLE DIFFERENCE BETWEEN A STRONG TROPICAL STORM AND A MINIMAL HURRICANE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 04/2100Z 25.5N 75.0W 55 KT

12HR VT 05/0600Z 27.2N 76.4W 55 KT

24HR VT 05/1800Z 30.3N 78.0W 60 KT

36HR VT 06/0600Z 33.9N 78.3W 60 KT…ON THE COAST

48HR VT 06/1800Z 37.5N 76.5W 50 KT…INLAND

72HR VT 07/1800Z 46.0N 65.5W 40 KT…EXTRATROPICAL

96HR VT 08/1800Z 51.0N 50.0W 40 KT…EXTRATROPICAL

120HR VT 09/1800Z 52.5N 32.5W 45 KT…EXTRATROPICAL

$$ FORECASTER FRANKLIN

Hurricane Ike Remains a Powerhouse: Hanna Resembles Nana September 4, 2008

for a more recent update on Ike & Hanna, CLICK HERE

Hanna More Like Nana, But Can Still Bite

For a remnant of Gustav Radar Loop and a Tropical Storm Hanna Radar Loop, CLICK HERE.

Hurricane Ike Forecast Track 11AM 0904

Basically nothing has changed from the last posting. Ike is still a very strong

Hurricane Ike Spaghetti Model 0904 12Z

hurricane. I guess the only real difference between now and 12 hours ago is that the Hurricane Ike Spaghetti Model Intensity Graph. Previously, it was all over the place with the models evenly stretched from it concluding as a tropical storm to it being a near Cat 5 hurricane. This time, the debate between models is largely between a strong Cat 3 to near Cat 5. The models seem to be coming together on Ike being a Big Bopper for some time. I explained why it is generally a tough row to hoe for a storm to stay strong over time. Tough but not

Hurricane Ike Spaghetti Model Intensity Graph 0904 12Z

impossible. Refer back that post for the explanation. Now you know why I’ve been saying since Ike first became a storm that I like Ike…now its time to be concerned about Ike.

Tropical Storm Hanna Forecast Track 11AM 0904

Other than that, Hanna is becoming increasingly boring and probably should be named Nana instead, since it seems increasingly to be a real dog. I told you last night that I

Tropical Storm Hanna Spaghetti Model 0904 12Z

had noted on several models some odditities that questioned the true tropical nature of Hanna in a few days. I didn’t tell you about the satellite photo, that looked odd to me too. Well, the NHC did not neglect to mention those items. That just brings into question the structure of the storm but does not pragmatically change the idea that the east coast will get wind, waves, somewhat higher tides and rain. Not a big deal but potentially problematic on a localized basis. Don’t pooh-pooh Hanna too much, but don’t go bananas either.

Josephine to me is too far out to fool with right now and I’m not to enthused about the position. At this early juncture I just have a notion that it will be a maritime concern…though it should not be dismissed altogether.

Tropical Storm Hanna Spaghetti Model Intensity Graph 0904 12Z

Tropical Storm Josephine Forecast Track 11AM

HURRICANE IKE DISCUSSION NUMBER 14
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008
1100 AM EDT THU SEP 04 2008

IKE CONTINUES TO DISPLAY A WELL-DEFINED EYE WITH VERY COLD CLOUD
TEMPERATURES IN THE EYEWALL. HOWEVER THE CLOUD PATTERN IS NOW
ASYMMETRIC DUE TO SOME NORTHERLY SHEAR AFFECTING THE CYCLONE.
OBJECTIVE AND SUBJECTIVE DVORAK CLASSIFICATIONS HAVE COME DOWN A
LITTLE BIT SO THE INITIAL INTENSITY IS REDUCED TO 120 KT. GLOBAL
MODELS UNANIMOUSLY INCREASE THE SHEAR OVER IKE AND KEEP STRONG
NORTHEASTERLY WINDS NEAR THE CYCLONE FOR THE NEXT FEW DAYS. THIS
PATTERN SHOULD INDUCE A STEADY WEAKENING. IN ADDITION…INNER-
CORE EYEWALL CYCLES COULD OCCUR…WHICH COULD WEAKEN IKE AS WELL.
IN THE LONGER-TERM…THE SHEAR IS FORECAST TO RELAX AND SOME
STRENGTHENING COULD OCCUR. HOWEVER…DEPENDING ON THE EXACT TRACK
OF IKE…THE HURRICANE COULD BE IMPACTED BY COOLER WATERS NEAR THE
SOUTHEASTERN BAHAMAS THAT HAVE BEEN STIRRED UP BY HANNA. THE
OFFICIAL FORECAST IS LOWER THAN THE PREVIOUS ONE BUT STILL SHOWS
IKE AS A POWERFUL HURRICANE THROUGHOUT THE PERIOD.

IKE CONTINUES TO MOVE WEST-NORTHWESTWARD…AT ABOUT 290/14…A
LITTLE SLOWER THAN BEFORE. A BEND TOWARD THE WEST AND WEST-
SOUTHWEST SEEMS PROBABLE AS A HIGH BUILDS IN TO THE NORTHWEST OF
IKE. THE STRENGTH OF THE HIGH IS THE BIG QUESTION MARK FOR FIRST
PART OF THIS FORECAST WITH THE MODELS BECOMING INCREASINGLY
DIVERGENT. THE MODELS HAVE SPLIT INTO TWO GENERAL CAMPS THIS
MORNING. THE UKMET/GFS/HWRF ALLOW THE CYCLONE TO GAIN A LITTLE MORE
LATITUDE INITIALLY…THEN SHOW LESS OF A WEST-SOUTHWESTWARD MOTION
OVER THE NEXT SEVERAL DAYS. HOWEVER ANOTHER GROUP OF MODELS…
COMPRISED OF THE NOGAPS/ECMWF/GFDN/GFDL…SHOW A FASTER TURN TOWARD
THE WEST AND WEST-SOUTHWEST AND SUGGEST MORE OF A THREAT TO THE
BAHAMAS. WITH CREDIBLE MODELS IN EACH GROUP…IT IS PROBABLY BEST
TO STAY FAIRLY CLOSE TO THE OVERALL MODEL CONSENSUS. THE OFFICIAL
NHC FORECAST IS CLOSE TO THE PREVIOUS ONE AND IS NEAR A
BIAS-CORRECTED GLOBAL MODEL CONSENSUS.

BECAUSE OF THE UNCERTAINTIES IN 4- AND 5-DAY TRACK FORECASTS…IT IS
STILL TOO EARLY TO SAY WHAT LAND AREAS ARE LIKELY TO BE IMPACTED BY
THIS HURRICANE. HOWEVER INTERESTS IN THE TURKS AND CAICOS ISLANDS
AND THE SOUTHEASTERN BAHAMAS SHOULD BE MONITORING THE PROGRESS OF
IKE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 04/1500Z 23.2N 57.0W 120 KT
12HR VT 05/0000Z 23.8N 58.9W 115 KT
24HR VT 05/1200Z 24.0N 61.3W 110 KT
36HR VT 06/0000Z 23.6N 63.8W 105 KT
48HR VT 06/1200Z 23.0N 66.7W 100 KT
72HR VT 07/1200Z 22.5N 71.0W 100 KT
96HR VT 08/1200Z 23.5N 74.5W 105 KT
120HR VT 09/1200Z 25.5N 77.5W 105 KT

$$
FORECASTER BLAKE

TROPICAL STORM HANNA DISCUSSION NUMBER 31…CORRECTED NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082008 1100 AM EDT THU SEP 04 2008 …CORRECT STATUS AT 48 AND 72 HR… VERY DRY AIR ASSOCIATED WITH THE UPPER-LEVEL LOW OVER THE NORTHWESTERN BAHAMAS IS CHOKING OFF CONVECTION NEAR THE CORE OF HANNA…AND THE CYCLONE HAS A VERY SUBTROPICAL APPEARANCE. CONVECTION HAS DIMINISHED SUBSTANTIALLY OVER THE PAST 6-12 HOURS AND THE HIGHEST FLIGHT-LEVEL AND SFMR WINDS HAVE COME DOWN AS WELL. BASED ON SOME 52 KT SFMR WINDS AROUND 11Z…THE INITIAL INTENSITY IS LOWERED TO 55 KT. CONDITIONS ARE NOT CONDUCIVE TO STRENGTHENING RIGHT NOW…WITH MODERATE SOUTHERLY SHEAR AND POOR THERMODYNAMICS. THE GFS SUGGESTS THAT DRY AIR IS LIKELY TO CONTINUE TO BE AN ISSUE UP TO LANDFALL. HOWEVER…AS HANNA AND THE UPPER LOW BEGIN TO SEPARATE SOME OF THE GLOBAL MODELS…INCLUDING THE GFS…SUGGEST THAT THE SHEAR WILL LESSEN SOMEWHAT. THIS WOULD ALLOW FOR SOME INTENSIFICATION…AND SO THE OFFICIAL FORECAST CONTINUES TO SHOW HANNA ATTAINING HURRICANE STRENGTH. THIS IS IN GOOD AGREEMENT WITH THE HWRF…ALTHOUGH THE GFDL AND SHIPS GUIDANCE IS LOWER. THE INITIAL MOTION IS 315/10. THE FORECAST SCENARIO IS UNCHANGED FROM PREVIOUS ADVISORIES. MID-LEVEL HIGH PRESSURE IS BUILDING OVER THE WESTERN ATLANTIC AS A DEEP LAYER LOW MOVES AWAY FROM NEW ENGLAND. HANNA IS EXPECTED TO RECURVE AROUND THE PERIPHERY OF THE HIGH AHEAD OF A MID-LATITUDE SHORT WAVE TROUGH IN THE WESTERLIES. MODEL GUIDANCE REMAINS IN FAIRLY GOOD AGREEMENT AND LITTLE CHANGE TO THE FORECAST TRACK IS REQUIRED. THE OFFICIAL FORECAST IS SLIGHTLY TO THE RIGHT OF THE MODEL CONSENSUS BECAUSE THE BETTER PERFORMING MODELS THIS YEAR…NAMELY THE GFS AND GFDL…ARE ON THE RIGHT SIDE OF THE GUIDANCE ENVELOPE. BECAUSE OF THE LARGE… SPRAWLING NATURE OF THE CIRCULATION…THE EXACT TRAJECTORY OF THE CENTER IS RELATIVELY UNIMPORTANT. FORECAST POSITIONS AND MAX WINDS INITIAL 04/1500Z 24.5N 73.5W 55 KT 12HR VT 05/0000Z 26.2N 75.2W 55 KT 24HR VT 05/1200Z 28.7N 77.2W 60 KT 36HR VT 06/0000Z 31.7N 78.2W 65 KT 48HR VT 06/1200Z 35.4N 77.4W 55 KT…INLAND 72HR VT 07/1200Z 43.0N 69.5W 40 KT…EXTRATROPICAL 96HR VT 08/1200Z 50.0N 54.0W 40 KT…EXTRATROPICAL 120HR VT 09/1200Z 51.5N 37.5W 45 KT…EXTRATROPICAL $$

Hurricane Ike Gains the Power of Tina; Tropical Storm Hanna Still a Menace September 4, 2008

for a more recent update on Hurricane Ike & Tropical Storms Hanna and Josephine, CLICK HERE.

Hurricane Ike at 0315Z Thursday. Its a compact put powerful storm.

For a Gustav Radar Loop or a Tropical Storm Hanna Radar Loop, CLICK HERE. Its not like a conventional

Like Tina, Tropical Ike Knows How to Steal the Show

radar that you can find on the web because you have the ability to navigate wherever you like. Even to street level and the resolution does not change…no confusing pixels. You get returns from all US radar installations and it would appear that Puerto Rico (US protectorate) as well. But, it seems there is hole in the Bahamas so Hannas returns will be limited until it move closer to full US radar range, though you can still get an idea of its motion. Click “animate” to loop and you can add lightning and clouds.

Hurricane Ike NHC Forecast 11pm 0903

As I had cautioned, Ike had the potential to become a big bopper. It zipped up even quicker than I had thought…I’d have at least given it a day. I also told you that Ike would certainly become the star of the show, much as Tina Turner outshined her Ike. Though I must say that her Ike was quite the polite traveller on the flight we shared. Anyway, I’ve told you all along that I like Ike better than its fellow storms Hanna and Josephine. I was speaking in terms of a meteorologist that marvels at the power and beauty of a fully formed hurricane. As a human and and American, Ike’s growth into maturity brings a sense of fear.

Hurricane Ike Spaghetti Model 0904 00Z

But let’s don’t give up just yet. Hurricane Ike is a 135 mph category 4 hurricane. it’s a long way out. Tropical Cyclones typically have a difficult time maintaining maximum intensity over time. This is part of the reason why the US has been struck by but a handful of such ferocious storms. A storm has to have perfect

Hurricane Ike Spaghetti Model Intensity Graph 0903 00Z

conditions to become a storm of great strength. Then, as it moves across the ocean, it has to have an environment that can support that intensity. The ocean water has to remain at least 80 degrees. It has to maintain some sense of forward motion. Otherwise, upwelling of colder water can become suicidal for an idle storm. The storm has to have an environment of supportive upper winds and that is very tough when a storm has to travel over a long distance. Time itself becomes an issue becuase the atmosphere is not static: it is in flux. So, sooner or later atmospheric conditions will become hostile. Then there is the internal structure. Dry air intrusion can serve as a dagger to a hurricane. Then of course, there is interaction with land. Relatively small Islands like Hispaniola and Cuba have tall mountains that can disrupt the circulation. That’s a lot of hurdles and I’ve left some out.

Hurricane Ike Intensity Probability Table 0903 11pm

So…Ike has a long way to go. The NHC feels like that there will be some shear in the near term that should act to limit the storm but the concern is that the shear will not be sufficient to really disrupt the storm that much. After a time, the storm is expected to move back into a favored environment and the forecast takes it right back to Cat 4 status. At that time its in the same region as Hanna has been hanging out. The question arises about how much upwelling in the region from Hanna’s pokiness will affect the storm. My guess is that as long as it keeps moving, it shouldn’t be too much of an issue. Besides that, the depth of the warm water in the region might negate the issue of upwelling. Then there’s the final issue. …where does it go from there?

After getting forced in the somewhat unconventional WSW motion, it will come around the ridge that is steering it. We have a strong trof coming through the Ohio Valley early next week. The question as to whether the trof is deep enough and far enough east to turn the storm away from the United States becomes germain. The storm should be very strong. Hurricane Ike has great potential and because of its proximity to the United States in the final days of the forecast time frame, it would be very wise for coastal concerns to keep up with Hurricane Ike. The Gulf of Mexico seems to be less likely scenario for a destination but it is not completely out of the question.

Tropical Storm Hanna Forecast Track 0903 11pm

Tropical Storm Hanna may become Hurricane Hanna again and will be a wind and

Tropical Storm Hanna Spaghetti Model Intensity Graph 0904 00Z

rain maker for the east coast. Certainly the eastern part of North Carolina. I explained before two things. One is that the exact landfall of Hanna will prove quite difficult due to the geography of the US coastline and the angle of attack. The second is that Hanna spent a long time getting the shoot kicked out of it and it stayed a long time over the same part of real estate. So, its a bit ragged. Some models that I saw even showed some signs of it losing

Tropical Storm Hanna Spaghetti Model 0904 00Z

tropical characteristics. But, so what? Its still an area of low pressure with high winds and strong storms and can create some tough seas. Its expected to turn extra-tropical after landfall and is not expected to be a major storm. It also should pick up speed rapidly as it moves up the east coast so the flooding concerns from Wilmington to Boston should be limited. Don’t take it too lightly though. Sometimes these guys that seem tame can cause unexpected problems. Its the things that we don’t anticipate that are often the most treacherous.

HURRICANE IKE DISCUSSION NUMBER 12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008
1100 PM EDT WED SEP 03 2008

IKE HAS RAPIDLY INTENSIFIED THIS EVENING. AN EYE BECAME APPARENT IN
CONVENTIONAL SATELLITE IMAGERY SHORTLY AFTER 2100 UTC. SINCE THAT
TIME THE EYE HAS BECOME MORE DISTINCT WITH A RING OF VERY COLD
CLOUDS TOPS SURROUNDING IT. THE LATEST DVORAK DATA T-NUMBERS WERE
T6.0 AND RAW ADT ESTIMATES FROM UW-CIMSS HAVE AVERAGED T6.2 SINCE
2045 UTC. BASED ON THESE ESTIMATES THE INITIAL INTENSITY IS SET
AT 115 KT…MAKING IKE A CATEGORY FOUR HURRICANE. SOME ADDITIONAL
STRENGTHENING IS POSSIBLE DURING THE NEXT 12 HOURS OR SO…THIS
WILL LARGELY BE CONTROLLED BY EYE-WALL REPLACEMENT CYCLES. HOWEVER
BOTH THE GLOBAL MODELS AND SHIPS GUIDANCE INDICATE INCREASING
NORTHEASTERLY SHEAR IN ABOUT 24 HOURS AND IT IS DIFFICULT TO
PREDICT HOW AN INTENSE HURRICANE LIKE IKE WILL BE AFFECTED BY THIS
SHEAR. THE NHC INTENSITY FORECAST INDICATES SOME WEAKENING BETWEEN
24-72 HOURS DUE TO THE SHEAR…BUT NOT AS MUCH AS INDICATED BY THE
SHIPS GUIDANCE. AT DAYS 4 AND 5…IT APPEARS THAT THE SHEAR WILL
DECREASE SO RE-STRENGTHENING IS PREDICTED AT THAT TIME.

THE INITIAL MOTION ESTIMATE IS 295/15. THE TRACK GUIDANCE AGREES
ON A CONTINUED WEST-NORTHWESTWARD MOTION DURING THE NEXT 24 HOURS.
DURING THE MIDDLE PORTION OF THE FORECAST PERIOD…A MID-LEVEL
RIDGE IS EXPECTED TO BUILD TO THE NORTH OF THE CYCLONE…AND THE
MODELS UNANIMOUSLY RESPOND BY TURNING IKE WEST-SOUTHWESTWARD. THE
LINGERING QUESTION THAT REMAINS AT THE LONGER RANGE IS WHEN IKE
WILL MOVE AROUND THE WESTERN PERIPHERY OF THE RIDGE. THE
MODEL SPREAD REMAINS QUITE LARGE AT DAYS 4 AND 5. THE GFDL IS ON
THE LEFT SIDE OF THE GUIDANCE WITH A TRACK NEAR HISPANIOLA AND
EASTERN CUBA…WHILE THE GFS AND UKMET SHOW A POSITION TO THE
NORTHEAST OF THE BAHAMAS. FOR NOW…THE OFFICIAL TRACK IS BETWEEN
THESE POSSIBLE SOLUTIONS AND IS IN BEST AGREEMENT WITH THE
HWRF…THE 12Z ECMWF…AND THE MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 04/0300Z 22.1N 54.1W 115 KT
12HR VT 04/1200Z 23.1N 56.2W 115 KT
24HR VT 05/0000Z 24.0N 58.7W 105 KT
36HR VT 05/1200Z 24.3N 61.0W 105 KT
48HR VT 06/0000Z 23.8N 63.6W 100 KT
72HR VT 07/0000Z 22.5N 68.5W 100 KT
96HR VT 08/0000Z 22.5N 72.0W 110 KT
120HR VT 09/0000Z 24.0N 75.5W 115 KT

$$
FORECASTER BROWN

TROPICAL STORM HANNA DISCUSSION NUMBER 29
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082008
1100 PM EDT WED SEP 03 2008

HANNA HAS BEEN A TENACIOUS TROPICAL CYCLONE. SINCE ITS FORMATION IT
HAS FOUGHT TWO UPPER-LEVEL LOWS…STRONG NORTHERLY SHEAR AND THE
EFFECTS OF LAND. FURTHERMORE…AT TIMES HANNA HAS RESEMBLED A
SUBTROPICAL CYCLONE. SURFACE AND AIRCRAFT OBSERVATIONS TONIGHT
CONTINUE TO SHOW THAT HANNA HAS A LARGE CIRCULATION AND SATELLITE
IMAGES SUGGEST THAT THE SHEAR IS DECREASING AND HANNA IS DEVELOPING
UPPER-LEVEL OUTFLOW. THESE CHANGES IN THE UPPER FLOW OVER HANNA
HAVE BEEN ACCURATELY FORECAST BY MOST OF THE NUMERICAL WEATHER
PREDICTION MODELS. THE INITIAL INTENSITY IS 55 KNOTS…AND IS
BASED ON A 68 KT FLIGHT-LEVEL WIND MEASURED AS THE PLANE DEPARTED
THE CYCLONE. WITH THE MORE FAVORABLE UPPER-LEVEL ENVIRONMENT…SOME
INTENSIFICATION IS INDICATED IN THE OFFICIAL FORECAST. HANNA IS
FORECAST TO REGAIN HURRICANE STATUS IN A DAY OR TWO BUT IT COULD
OCCUR EARLIER. NONE OF THE GUIDANCE INTENSIFIES HANNA BEYOND 70
KNOTS.

THE CENTER HAS BEEN ROTATING AROUND A LARGE CYCLONIC GYRE AND FIXES
FROM THE RECONNAISSANCE PLANE AND DATA FROM A NOAA BUOY SUGGEST
THAT THE INITIAL MOTION IS 335/11. SOME OF THIS MOTION COULD HAVE
RESULTED FROM REFORMATION OF THE CENTER. SINCE THE SUBTROPICAL RIDGE
IS EXPANDING TO THE NORTHEAST OF HANNA…A NORTHWEST MOTION SHOULD
CONTINUE DURING THE NEXT DAY OR TWO WITH A GRADUAL TURN TO THE
NORTH AROUND THE WESTERN EDGE OF THE HIGH. THE TRACK
MODELS ARE NOT TIGHTLY CLUSTERED AND THE CONFIDENCE IN THE TRACK
FORECAST IS NOT VERY HIGH. HOWEVER…THE MIDDLE OF THE GUIDANCE
ENVELOPE HAS HANNA MOVING OVER OR VERY CLOSE TO THE COAST OF THE
CAROLINAS. BECAUSE HANNA IS A LARGE CYCLONE…A HURRICANE WATCH
WILL LIKELY BE REQUIRED FOR A PORTION OF THE SOUTHEASTERN UNITED
STATES COAST EARLY THURSDAY.

A NOAA JET HAS SAMPLED THE ENVIRONMENT TONIGHT AND THE DATA IS BEING
USED TO INITIALIZE THE 00Z GLOBAL MODEL RUNS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 04/0300Z 23.2N 72.1W 55 KT
12HR VT 04/1200Z 24.7N 73.1W 55 KT
24HR VT 05/0000Z 26.9N 75.0W 60 KT
36HR VT 05/1200Z 29.3N 77.3W 65 KT
48HR VT 06/0000Z 32.0N 79.0W 70 KT
72HR VT 07/0000Z 39.5N 74.0W 50 KT…INLAND
96HR VT 08/0000Z 46.5N 63.0W 35 KT…EXTRATROPICAL
120HR VT 09/0000Z 49.0N 47.0W 35 KT…EXTRATROPICAL

$$
FORECASTER AVILA

Hurricane Ike Is Born; Tropical Storm Hanna On Bahamian Holiday September 3, 2008

Say Hello to Hurricane Ike above

for a more recent update on Tropical Storm Hanna and Hurricane Ike, CLICK HERE

For a Gustav Radar Loop and a Tropical Storm Hanna Radar loop, click here and navigate to your desired location.

Hurricane Ike NHC Forecast Track 5pm 0903

I’ve been telling you that I like Ike and so I’m going to start off with Ike, even though Hanna is closer to the United States.  Tropical Storm Ike became Hurricane

Hurricane Ike Spaghetti model Intensity Graph 0903 18Z

 Ike as expected at 5 pm on Wednesday.  Winds are projected at 80 mph and the storm is moving northwest but a ridge it should encounter a building ridge that is pretty formidable as it is forecast to be strong enough to shove it with a soutwesterly component for several days.  Now, the outperiods are the question marks as the storm swings into the Bahamas, the spaghetti model indicates that a number of models want to start to swing the storm northwest toward the Florida peninsula.  That is in response to a strong trof moving through the Ohio

Hurricane Ike Spaghetti Model 0903 18Z

Valley which will cool things off in Louisville appreciably.  That trof is running a little ahead of schedule and that is part of the key.  If the trof comes faster and deeper, it will pick up the storm just off the SE Florida coast, posing a threat to Florida and the East Coast.  If the trof does not dig as deep as progged, the storm moves faster or the trof moves slower, then that would provide the opportunity for Ike to head to the Gulf, which is what earlier models suggested.  But the ECMWF was one of the first models to pick up on this earlier turn and now many of the others have followed suit.  As I’ve said before, its a long way out and there is lots of time but Ike looks to be in a good spot to get going pretty good.  Questions arise when it gets into the Bahamas.  Hanna has been churning up the water in that area. And, our long wave pattern is looking kinda fall-like and that may increase the chances of a more hostile environment down the line.  Lots of time and space, lots of variables.

Tropical Storm Hanna NHC Forecast Track 5pm 0903

Tropical Storm Hanna has gotten beaten up pretty good. Its delay has allowed for

Tropical Storm Hanna Spaghetti Model Intensity Graph 0903 18Z

the trof that was to pick up the storm and turn it into the SE will be farther along.  So, as the storm finally gets going with a northwestward trajectory, it will get picked up well before it approaches the Florida coast and turn sooner, making the landfall more of a glancing blow to the eastern side of North Carolina.  Places like Wilmington and Cape Hatteras will get some action from a minimal hurricane (maybe) but much of the SE will be spared.  I noted some odd looking data for a tropical cyclone on some of the

Tropical Storm Hanna Spaghetti Model 0903 18Z

models yesterday and now the NHC has it losing tropical characteristics pretty quickly and shoot it up the east coast like squeezing a wet watermelon seed.  Hanna does not look particularly menacing and out ahead of it, perhaps and onshore flow will bring much needed rain to Western North Carolina and Eastern Tennesee.

Josephine is way out there still and as we get deeper into September, it may prove difficult for it to be of anything more than a maritime concern.  Here is the track nonetheless.  The following is the National Hurricane Center Forecast Discussion for Hurricane Ike then the National Hurricane Center Forecast Discussion for Tropical Storm Hanna.

HURRICANE IKE DISCUSSION NUMBER  10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL092008
500 PM EDT WED SEP 03 2008

AS ANTICIPATED…IKE HAS CONTINUED TO STRENGTHEN AND ALL
SATELLITE-BASED ESTIMATES SAY IT HAS BECOME A HURRICANE.  SINCE THE
1800 UTC DVORAK ESTIMATES OF 65 KT…AN EYE HAS BECOME APPARENT IN
LATE-DAY VISIBLE IMAGERY…SO THE INTENSITY IS SET TO 70 KT.  THE
CYCLONE IS INTENSIFYING WITHIN A COCOON OF NEARLY ZERO VERTICAL
WIND SHEAR…IN BETWEEN THE DEEP-LAYER LOW OVER THE NORTHWESTERN
ATLANTIC AND AN UPPER-LEVEL TROUGH DOMINATING THE EASTERN PORTION
OF THE BASIN.  WATER VAPOR IMAGERY REVEALS THAT THE UPPER-LEVEL
NORTHERLIES ALONG THE WESTERN FLANK OF THE EASTERN TROUGH ARE
STARTING TO JUST SLIGHTLY RESTRICT IKE’S OUTFLOW.  GLOBAL MODELS
FORECAST THE SHEAR TO INCREASE FROM THE EAST…BUT PROBABLY NOT
QUICKLY ENOUGH TO HALT IKE’S INTENSIFICATION TREND IN THE SHORT
TERM.  THE NEW OFFICIAL FORECAST SHOWS AN INTERMEDIATE INTENSITY
PEAK AT 24 HOURS PRIOR TO THE ONSET OF THE SHEAR…FOLLOWED BY
SLIGHT WEAKENING UNTIL THE SHEAR ABATES AFTER IKE GETS FARTHER
WEST.  BY THAT TIME…IN ABOUT 72 HOURS…OCEAN AND ATMOSPHERIC
FACTORS BECOME QUITE CONDUCIVE FOR INTENSIFICATION…AND THE
DYNAMICAL MODELS GFDL AND HWRF…FORECAST A MAJOR HURRICANE BY DAYS
4 AND 5…WHICH IS ALSO SHOWN IN THE OFFICIAL FORECAST.  LONG-RANGE
INTENSITY FORECASTS ARE RATHER UNCERTAIN…HOWEVER…AND THE
INTENSITY PROBABILITY TABLE INCLUDED IN THIS ADVISORY PACKAGE
INDICATES THAT THERE IS ROUGHLY A 50 PERCENT CHANCE THAT IKE WILL
BE A MAJOR HURRICANE FOUR AND FIVE DAYS FROM NOW.  IF IKE IS WEAKER
THAN THE OFFICIAL FORECAST AT DAYS 3-5…THEN THE
STATISTICAL-DYNAMICAL MODELS SHIPS AND LGEM WILL TURN OUT TO BE
MORE ACCURATE.

THE HURRICANE CONTINUES HEADING WEST-NORTHWESTWARD OR 290/16.  AS
THE LARGE AND DEEP-LAYER LOW CURRENTLY JUST OFF THE NORTHEAST
U.S. COAST DEPARTS TO THE NORTHEAST…MID-LEVEL RIDGING WILL BUILD
OVER THE WESTERN ATLANTIC…WHICH WILL PUSH IKE GENERALLY WESTWARD
DURING THE NEXT SEVERAL DAYS.  UNDULATIONS IN THE TRACK ARE
LIKELY THOUGH.  IKE SHOULD CONTINUE WEST-NORTHWESTWARD UNTIL THE
WESTERN ATLANTIC RIDGE FORMS…AFTER WHICH THE TROPICAL CYCLONE
WILL GRADUALLY ROUND THAT RIDGE.  THE BIG QUESTION AT LONGER RANGES
IS IF AND WHEN IKE WILL ROTATE AROUND THE WESTERN PERIPHERY OF THAT
RIDGE…WHICH WILL DETERMINE WHETHER IKE DIRECTLY AFFECTS ANY LAND
AREAS.  THE MODELS DO NOT PROVIDE AN UNANIMOUS ANSWER…WHICH IS
NOT SURPRISING THIS FAR IN ADVANCE.  ALL OF THE MODELS DO SHOW THE
BEGINNINGS OF A MOTION NORTH OF DUE WEST BY DAY 5…BUT IT IS TOO
EARLY TO DETERMINE IF THIS IS THE START OF RECURVATURE…OR IF
ENOUGH RIDGING WILL REMAIN BEYOND DAY 5 TO KEEP IKE MOVING
GENERALLY WESTWARD.

FORECAST POSITIONS AND MAX WINDS

INITIAL      03/2100Z 21.6N  52.7W    70 KT
12HR VT     04/0600Z 22.6N  55.1W    75 KT
24HR VT     04/1800Z 23.8N  57.9W    85 KT
36HR VT     05/0600Z 24.3N  60.4W    80 KT
48HR VT     05/1800Z 23.8N  63.1W    80 KT
72HR VT     06/1800Z 22.5N  68.0W    90 KT
96HR VT     07/1800Z 22.5N  72.0W   100 KT
120HR VT     08/1800Z 23.5N  76.0W   100 KT

$$
FORECASTER KNABB
TROPICAL STORM HANNA DISCUSSION NUMBER  28
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL082008
500 PM EDT WED SEP 03 2008

AN ASCAT PASS FROM 14Z REVEALED THAT THE LOW-LEVEL CIRCULATION OF
HANNA WAS BECOMING ELONGATED IN RESPONSE TO THE ASYMMETRIC
DISTRIBUTION OF CONVECTION.  IN SPITE OF THIS…DATA FROM THE
RECONNAISSANCE AIRCRAFT INDICATE THAT HANNA IS BECOMING A LITTLE
BETTER ORGANIZED.  TROPICAL STORM FORCE WINDS HAVE RETURNED TO THE
SOUTHWEST QUADRANT AND THE PRESSURE HAS FALLEN TO 989 MB.  THE
AIRCRAFT DATA CONTINUE TO SUGGEST THAT THE MAXIMUM WINDS ARE ABOUT
50 KT.

A MORE DEFINITIVE NORTHWARD MOTION HAS COMMENCED…WITH THE INITIAL
ESTIMATE BEING 360/10.   THE UPPER LOW OFF OF NEW ENGLAND IS
BEGINNING TO MOVE OUT…AND AS IT DOES SO MID-LEVEL RIDGING WILL
BUILD IN BEHIND IT.  HANNA SEEMS TO BE FOLLOWING THE CONVECTION
FAIRLY WELL…AND I’VE HAD TO SPEED UP MY PREVIOUS FORECAST A
LITTLE BIT.  THE OFFICIAL FORECAST IS IN BEST AGREEMENT WITH A
BLEND OF THE ECMWF AND THE GFS.  THE HWRF AND GFDL CONTINUE TO BE
FASTER THAN THE OFFICIAL FORECAST…AND IF HANNA DEVELOPS FASTER
THAN SHOWN BELOW ADDITIONAL TIMING ADJUSTMENTS MAY NEED TO BE MADE.
IT’S WORTH NOTING THAT CONNECTING THE 48 AND 72 HOUR FORECAST POINTS
WITH A STRAIGHT LINE GIVES A MISLEADING UNDERESTIMATE OF THE
THREAT TO THE GEORGIA AND SOUTH CAROLINA COASTS.  ONLY A GRADUAL
RIGHT TURN IS EXPECTED AFTER 48 HOURS.

AS THE UPPER LOW IN THE BAHAMAS AND HANNA SEPARATE…THE SOUTHERLY
SHEAR OVER THE CYCLONE WILL TURN SOUTHEASTERLY AND LESSEN.  THIS IS
EXPECTED TO PROVIDE A MORE FAVORABLE ENVIRONMENT FOR
STRENGTHENING…ALTHOUGH NONE OF THE OBJECTIVE AIDS SHOWS VERY
MUCH.  THE SHIPS AND LGEM BRING THE SYSTEM ONLY TO 60 KT…AND THE
HWRF NOT QUITE THAT HIGH.  THE OFFICIAL FORECAST IS IN GOOD
AGREEMENT WITH THE GFDL WHICH BRINGS HANNA TO 70 KT PRIOR TO
LANDFALL.

FORECAST POSITIONS AND MAX WINDS

INITIAL      03/2100Z 21.9N  71.9W    50 KT
12HR VT     04/0600Z 23.2N  72.7W    55 KT
24HR VT     04/1800Z 25.2N  74.5W    60 KT
36HR VT     05/0600Z 27.4N  76.6W    65 KT
48HR VT     05/1800Z 30.0N  78.5W    70 KT
72HR VT     06/1800Z 36.8N  76.9W    50 KT…INLAND
96HR VT     07/1800Z 44.5N  67.0W    35 KT…EXTRATROPICAL
120HR VT     08/1800Z 48.0N  55.0W    35 KT…EXTRATROPICAL

$$
FORECASTER FRANKLIN

Tropical Storm Ike Shaping Up Like Tina; Tropical Storm Hanna Fading September 3, 2008

for a more recent update on ike and hanna, Click here

I like Ike….just look at it above…shaping up like Tina!!

For a Gustav Radar Loop or a Tropical Storm Hanna Radar Loop, CLICK HERE

Tropical Storm Hanna NHC Forecast Track 11AM 0903

I’m not going to write too much this time.  Hanna is getting the shoot kicked out

Tropical Storm Hanna Spaghetti Model 0903 12Z

of it by shear.  Its starting to drift north and the spaghetti models are getting together in suggesting that it may even stay off shore.  The NHC has shifted its forecast track east but not completely toward the consensus….yet.  The storm is becoming less interesting and less of a threat.  It’s taken so much time in the islands that an upper low has now wandered in to mess it up and the delay also make it so the trof picks it up before it gets to the coast since it stayed on schedule.

Tropical Storm Ike NHC forecast Track 11AM 0903

I still like Ike.  Ike is rounding into shape more like Tina Turner than Ike Turner as I suspect it will at some time become a beautifully formed storm.  Once this upper

Tropical Storm Ike Spaghetti Model 0903 12Z

 low that is menacing Hanna moves through, ridging will build in and the course of Ike would shift west, if not slightly south of west.  The official forecast takes it into the Florida Straits.  Still the same question that I had last time which regards the depth of the front coming through here on Tuesday. It’s pretty strong and so if it digs far enough South, then it would pick up Ike and turn it toward the coast.  If Ike keeps up a good pace, then it should get south of the

Tropical Storm Ike Spaghetti Model Intensity Graph 0903 12Z

Florida Peninsula before it can get picked up and then turn up toward say the Panhandle.  The the front beats it to the coast, then it would turn up into the peninsula.  BUT…if the trof doesnt dig deep enough leaving Ike farther south, then it would slip underneath and head into the Gulf, threatening the northern Gulf if not the western Gulf.    Some support for this notion lies in the ridge flattening out along the Dixie states with the trof not getting far south and Ike getting sent on its merry way…essentially, the ridge stands between the front and the hurricane.  Lots of time…lots of things can happen. I just outlined three of them.  But I’m tellin’ you…I still like Ike.  I suspect that it will be a hurricane soon and has big bopper potential. Some time I’ll tell you about my sitting by Ike Turner on a flight from Louisville to Houston.

TROPICAL STORM IKE DISCUSSION NUMBER   9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL092008
1100 AM EDT WED SEP 03 2008

IKE IS WRAPPING UP SOME SOLID CONVECTIVE BANDING AS VIEWED IN
VISIBLE IMAGERY…AND SINCE A PARTIAL OVERPASS SEVERAL HOURS AGO
FROM AMSR-E SUGGESTED A MICROWAVE EYE WAS FORMING…WE MIGHT SEE AN
EYE IN THE VISIBLE BEFORE TOO MUCH LONGER.  SUBJECTIVE DVORAK
T-NUMBERS AT 1200 UTC WERE A CONSENSUS 4.0…BUT OBJECTIVE NUMBERS
ARE A LITTLE LOWER…SO THE INTENSITY IS SET TO 60 KT FOR NOW.  IN
ANY CASE…IKE IS ON THE CUSP OF BEING A HURRICANE AND SHOULD BE
ONE LATER TODAY.  THE UNDERLYING OCEAN TEMPERATURES WILL ONLY GET
WARMER ALONG THE FORECAST TRACK…MAXIMIZING BEYOND 48 HOURS NEAR
29 CELSIUS…WHICH WOULD FAVOR A STRENGTHENING TREND THROUGHOUT THE
FIVE-DAY PERIOD.  DURING THE NEXT COUPLE OF DAYS…HOWEVER…IKE
MIGHT ENCOUNTER A LITTLE INCREASE IN WIND SHEAR FROM THE NORTH
BEHIND THE MID-LATITUDE TROUGH THAT WILL BE TRAVERSING THE
NORTHWESTERN ATLANTIC.  THE OBJECTIVE GUIDANCE DOES NOT FORECAST
ANY WEAKENING AS A RESULT…BUT NONE OF THE MODELS FORECAST ROBUST
STRENGTHENING…UNTIL IKE HEADS FARTHER WEST…ESCAPES THE
SHEAR…AND MOVES OVER EVEN WARMER WATERS NEAR THE GREATER
ANTILLES.  STEADY STRENGTHENING IS FORECAST AT DAYS 3-5 IN LINE
WITH MOST OF THE INTENSITY MODELS…AND IKE COULD REACH MAJOR
HURRICANE STATUS BEFORE FIVE DAYS PASS.

IKE CONTINUES WEST-NORTHWESTWARD OR 285/16 ALONG THE SOUTHWESTERN
PERIPHERY OF A MID-LEVEL RIDGE OVER THE CENTRAL ATLANTIC.  THE
MODELS FORECAST IKE TO BEND A LITTLE TO THE RIGHT AROUND THAT
RIDGE…BUT IN A COUPLE OF DAYS IT WILL RUN INTO A RIDGE BUILDING
OVER THE WESTERN ATLANTIC.  NEARLY ALL OF THE MODELS AGREE THAT
THIS PATTERN WILL FORCE IKE WEST-SOUTHWESTWARD AND EVENTUALLY
WESTWARD AROUND THE SOUTHERN PERIPHERY OF THAT FEATURE…BUT THEY
DO NOT AGREE ON THE EXACT LATITUDE OR THE SPEED OF THAT WESTWARD
MOTION.  THE CONSENSUS HAS SLOWED DOWN A LITTLE LATE IN THE
FIVE-DAY PERIOD…AND SO HAS THE OFFICIAL FORECAST TRACK…BUT
OTHERWISE THE NEW TRACK IS SIMILAR TO THE PREVIOUS ONE…EXCEPT FOR
A LITTLE MORE NORTHWARD PROGRESS WITHIN THE NEXT COUPLE OF DAYS.

FORECAST POSITIONS AND MAX WINDS

INITIAL      03/1500Z 20.8N  51.2W    60 KT
12HR VT     04/0000Z 21.7N  53.7W    65 KT
24HR VT     04/1200Z 23.1N  56.8W    70 KT
36HR VT     05/0000Z 23.8N  59.4W    70 KT
48HR VT     05/1200Z 24.0N  62.0W    70 KT
72HR VT     06/1200Z 22.5N  67.0W    80 KT
96HR VT     07/1200Z 22.0N  71.5W    90 KT
120HR VT     08/1200Z 22.5N  75.5W   100 KT

$$
FORECASTER KNABB
TROPICAL STORM HANNA DISCUSSION NUMBER  27
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL082008
1100 AM EDT WED SEP 03 2008

Tropical Storm Hanna Spaghetti Model Intensity Graph 0903 12Z

THERE HAVE BEEN SOME STRUCTURAL CHANGES WITH HANNA TODAY AS IT
INTERACTS WITH THE UPPER-LEVEL LOW MOVING THROUGH THE NORTHWESTERN
BAHAMAS.  THE WIND FIELD HAS EXPANDED IN THE NORTHERN SEMICIRCLE
AND THE LOW-LEVEL CIRCULATION CENTER HAS BECOME LESS WELL DEFINED.
VISIBLE IMAGERY SUGGESTS MULTIPLE LOW-LEVEL SWIRLS COMING OUT OF
THE DEEP CONVECTION TO THE NORTH OF A MEAN CENTER…AND THE
SYSTEM’S CONVECTIVE BANDS ARE WELL REMOVED FROM THE CORE.  THE
RECONNAISSANCE MISSION THAT ENDED AROUND 12Z REPORTED SOME SFMR
WINDS OF UP TO 45 KT ABOUT 70 NM FROM THE CENTER…AND THE INITIAL
INTENSITY ESTIMATE REMAINS 50 KT.

BECAUSE THE CENTER IS NOT WELL DEFINED…THE INTIAL MOTION IS HARD
TO GAUGE.  MY BEST ESTIMATE IS 360/5…AND THIS COULD BE THE START
OF THE EXPECTED NORTHWESTWARD TURN.  THE STEERING FLOW SHOULD
BECOME BETTER DEFINED OVER THE NEXT 24-48 HOURS AS THE UPPER LOW
MOVES WEST-SOUTHWESTWARD AND MID-LEVEL RIDGING BUILDS IN BEHIND THE
LARGE DEEP-LAYER LOW OFF THE UPPER U.S. EAST COAST.  MODEL GUIDANCE
RESPONDS TO THIS PATTERN WITH A NORTHWESTWARD ACCELERATION WITH A
RECURVATURE AROUND THE MID-LEVEL RIDGE IN ABOUT THREE DAYS.  THE
GUIDANCE HAS BEEN TOO FAST WITH THIS SCENARIO OVER THE PAST COUPLE
OF DAYS…AND GIVEN THE POOR CORE STRUCTURE OF HANNA I AM INCLINED
TO THINK THAT SUBSEQUENT INTERACTION WITH THE UPPER STEERING MAY BE
A LITTLE OVERDONE…AT LEAST INITIALLY.  THE OFFICIAL FORECAST IS
IN BEST AGREEMENT WITH THE ECMWF AND UKMET IN TERMS OF SPEED…WITH
THE GFS/HWRF/GFDL SHOWING A MORE VERTICAL SYSTEM MOVING MORE
RAPIDLY.  THE GUIDANCE HAS ALSO BEEN TRENDING EASTWARD OVER THE
PAST FEW CYCLES…AND I HAVE SHIFTED THE TRACK SLIGHTLY IN THAT
DIRECTION.

WESTERLY SHEAR AND DRY AIR ASSOCIATED WITH THE UPPER LOW WILL
INHIBIT DEVELOPMENT IN THE SHORT TERM BUT SHOULD DIMINISH OVER THE
NEXT COUPLE OF DAYS…TO BE REPLACED WITH MODERATE SOUTHEASTERLY
SHEAR.  THIS PATTERN WOULD PERMIT SOME RE-INTENSIFICATION…BUT
HANNA WILL NEED TO RECREATE AN INNER CORE IN ORDER TO INTENSIFY
SUBSTANTIALLY.  THE AVAILABLE GUIDANCE STILL BRINGS HANNA TO
MINIMAL HURRICANE INTENSITY AND THE OFFICIAL FORECAST IS JUST ABOVE
THIS GUIDANCE.

FORECAST POSITIONS AND MAX WINDS

INITIAL      03/1500Z 20.6N  71.8W    50 KT
12HR VT     04/0000Z 21.5N  72.0W    50 KT
24HR VT     04/1200Z 23.4N  73.3W    55 KT
36HR VT     05/0000Z 25.2N  75.2W    60 KT
48HR VT     05/1200Z 27.3N  77.1W    65 KT
72HR VT     06/1200Z 33.0N  79.0W    70 KT
96HR VT     07/1200Z 42.0N  71.0W    35 KT…INLAND EXTRATROPICAL
120HR VT     08/1200Z 47.0N  60.0W    35 KT…EXTRATROPICAL

$$
FORECASTER FRANKLIN

Tropical Storm Hanna and Tropical Storm Ike Hope Life is Like George Bush, Not Wilbur Wright September 3, 2008

for a more recent update on Hanna and Ike, CLICK HERE

For access to a Gustav Radar Loop or a Tropical Storm Hanna Radar Loop, CLICK HERE.

Information on Tropical Storm Hanna, Tropical Storm Ike and Tropical Storm Josephine can be found below.

Louisville Weather: Bad news…its going to stay hot and dry. Good news is that the threat of Tropical Storm Hanna becoming a strong, well developed Hurricane has diminished so its track should not allow for any subsidence to speak of to reach the Ohio Valley and so a front on Friday will be able to bring some moisture from Gustav into the area. You won’t have to build an ark and the rain will just by scattered in nature, but something is better than nothing. A better chance for area-wide rain shows up with a strong cold front Tuesday. Temperatures do back off for the weekend with Hanna’s passing and the advance of the front.

Wilbur Not As Lucky As Orville

On This Date in History: On this date in 1908, Orville and Wilbur Wright made their first public demonstration of their airplane. Actually, it wasn’t the same Wright Flyer that made the historic flight in December 1903. They had made a number of improvements over nearly 5 years, but no one really noticed. The day that they made their initial flight, they had invited the press but no one came. Instead, they had been focused on the ill-fated attempt at heavier than air flight by the more celebrated Samuel Pierpont Langley. Following the Wright’s flight at Kitty Hawk, NC the New York Daily Tribune printed a small story with the headline “Dayton Boys Fly Airship.” The newspaper obviously had no clue as to what they had accomplished. After that, the Wrights worked on improving their “airship” but even the farmers weren’t interested. A farmer once watched the Wrights fly a plane near Dayton, Ohio 24 miles in 38 minutes, but he didn’t even stop plowing his field. Well, the brothers on this date in 1908 began a series of demonstrations for the Army at Fort Myer, Virginia and the public was invited. The demonstrations went on for several days and it took but two short weeks for the Wrights to achieve a somewhat infamous aviation record when on September 17, Orville took Lt. Thomas E Selfridge on a ride to demonstrate the potential military value of the airplane. A guy wire broke and got tangled in a propeller and the plane “came down like a bird shot dead in full flight.” Orville shattered his hip and left leg but Selfridge was killed, going in the record book as the first aviation crash and first aviation fatality. So Orville got to make the first flight, was the first to crash, the first to be in a fatal air crash. Meanwhile, poor old Wilbur was the first Wright born on my birthday, the first to get typhoid fever around the time that the Titanic sunk in April 1912 and was the first Wright to die when he succumbed a month later. Talk about bad breaks…

Lt. George H. W. Bush is Rescued

On this date in 1944, a young Lieutenant pilot was recovering on a US submarine after his plane crash. He went to to at least earn the same fame as Orville Wright. Lt. George Bush was but 20 years old when his plane was shot down over the Pacific Ocean by enemy anti-aircraft fire. His two crewmen were killed. One of them was killed in the aircraft while the other bailed out with Bush. But, only Bush’s parachute opened. After paddling around in a life raft for 4 hours, Lt. Bush was picked up by the USS Finback. But the sub had other things to do and Bush spent the next month on board while the Finback continued its mission. Bush spent his time assisting in picking up other downed pilots. For his heroism and actions during numerous sorties (58 missions in 1944 alone) Bush received the Navy’s Distinguished Flying Cross, three Air Medals and a Unit Citation shared with the rest of the crew of the USS Jacinto. He went on to be a Congressman, Ambassador to the UN, CIA Director, Vice-President, President of the United States and only the second former President to have a son also hold the nation’s highest elective office. Imagine all that the nation would have missed had the Finback not been in the area. You never know what one good turn can lead to.

1890 Census Tabulating Machine; Uncle Sam Has Been Nosey Ever Since

One thing we do know that we can count on is government bureaucracy and its been going on since the beginning of our Republic. The Constitution calls for a census to be taken every ten years in order to determine, among other things, the representation in the House of Representatives from each state. The first census of 1790 took 18 months to complete. So, one hundred years later they got smart and decided to get smart and introduced the world’s first punch-card tabulation system. Should happen fast, right? Wrong. See, the boys in the Capitol thought that the new machine gave them Carte-Blanche to not just take basic information, but instead collect all sorts of information. The form consisted of 13,000 pieces of information!!! Talk about an intrusive government….and it’s been getting nosier by the day ever since.

Tropical Storm Hanna NHC Forecast track 11pm 0902

Tropical Storm Hanna. Nothing much has changed since the previous update.

Tropical Storm Hanna Spaghetti Model 0903 00Z

For part of the day Tuesday, Hanna was loitering east of the Bahamas and actually drifing Southeast. It spent much of the day getting kicked by upper level shearing and its hanging out in one area didn’t do itself any favors as for water temperatures. But, its still expected to get moving and swing along the Florida coast with a landfall near Savannah Georgia, though this forecast track is on the left edge of the model consensus. It is expected to reach only a cat 1 status. The exact landfall will be difficult to pinpoint given the geography of the coastline but at this time it appears that it will mainly be a story of beach erosion and rain issues.

Tropical Storm Ike NHC Forecast Track 0902 11PM

Tropical Storm Ike: Tropical Storm Ike still looks like a potential trouble maker

Tropical Storm Ike Spaghetti Model 0903 00Z

on down the road. The spaghetti model indicates that the greatest clustering of tracks takes it westward through Bahamas and across Cuba into the Gulf. Indications are that it will intensify into a formidable storm before crossing Cuba. What happens after that remains to be seen how it handles the mountains of Cuba and atmospherice conditions thereafter. Both the GFS and CMC models keep it south of Florida. The ECMWF has a different solution. It takes it through the Bahamas and then tends to move it slightly north of west toward the southern tip of Florida by Tuesday. This is perhaps in response to a strong cold front moving through the Ohio Valley at that time. It may be day or so soon with turning the storm in response to the trof but it raises an interesting question regarding the front. If it digs far South, then the front would pick up Ike and turn it toward the US. If Ike is able to sneak below the trof, then it would open the door for a storm going deeper into the Gulf of Mexico. It will be interesting to see how it shakes out…but I still think Ike is going to be a trouble maker.

Tropical Storm Josephine is still a long way out with many scenarios and with many miles and days before it becomes an issue with which I care to concern myself. So you shouldn’t worry about it either.

Gustav Rains While Tropical Storm Hanna Dawdles and Tropical Storm Ike Churns Along September 2, 2008

Gustav Weakened But Still Cost Billions

Hurricane Gustav Damage Estimates Lowered-LINK TO STORY

For a Gustav Radar Loop or a Tropical Storm Hanna Radar Loop, CLICK HERE

for a more recent update on Tropical Storm Hanna and Tropical Storm Ike CLICK HERE

0902 5 Day Forecast Rainfall (QPF) Thru Sun AM

Tropical Depression Gustav is lurking in NE Texas and will continue to lumber along and probably get ripped apart and stretch into the plains. The moisture will be try to get to the Ohio Valley but activity will be suppressed, in spite of a frontal zone in the area. So far, rain fall totals from radar estimates have been in the 5-10 inch range in Louisiana but rain should continue for the next couple of days. Because Gustav has been moving, the catastrophic rain amounts for this week may not come to fruition.

Tropical Storm Hanna NHC Forecast Track 0902 5PM

Tropical Storm Hanna is just hanging around in the islands. It’s even been drifing SE! It is expected to get caught up in a trof and begin a northwestward motion and

Tropical Storm Hanna Spaghetti Model Intensity Graph 0902 18Z

approach Florida. Then it would swing more NNW and the point of landfall will be rather difficult given the approach is at such a small angle relative to the coast. If you’ve been following along, the track has gone from Savannah to Wilimington to the middle of SC, back to Savannah and now back to north of Savannah. Changes of just a few miles of the track as it swings around can alter the landfall point by many miles. If you recall a similar situation with

Tropical Storm Hanna Spaghetti Model 0902 18Z

Hurricane Charlie several years ago when it went up the western coast of Florida. It was forecast to go in near Tampa but went in well north of Fort Myers. The media went nuts but the landfall was in the broad forecast place (the cone) and was in the hurricane warning area. It’s for that reason that the NHC reiterates not to focus on the specific spot of the landfall. In the case of Hanna, it will be important to remember that as the geography will make it very difficult. Hanna is not forecast to become much more than a minimal hurricane and the spaghetti intensity models are not enthused about making it much more than a tropical storm. At this point, with the environmental conditions as they are, it appears this will be mainly remembered as a rain maker, hopefully some of that will get to eastern Tennessee that needs the rain badly. The 5 pm National Hurricane Center Tropical Storm Hanna Discussion is below.

Tropical Storm Ike NHC Forecast Track 5PM

I still think that Tropical Storm Ike is a potential troublemaker. A ridge expands and builds in taking Ike almost due west after it initially moves WNW prior to the

Tropical Storm Ike Spaghetti Model Intensity Graph 0902 18Z

expansion of the ridge. One of the models on the Spaghetti Intensity Graph rapidly take this to nearly a cat 5. The boys at the National Hurricane Center are discounting this model….though they did mention it in the discussion, which raises my eyebrow a bit. Nevertheless, conditions are decent for development and if the ridge does what it is supposed to do, then Ike would get driven toward Cuba and, presumably, into the Gulf. There are a lot of

Tropical Storm Ike Spaghetti Model 0902 18Z

things than can happen to mess Ike up but nothing really jumps out at me. It would run over the upwelled water of Hanna’s dawdling in the Bahamas. But, I suspect that the depth of the water is relatively deep so the upwelled water may not be that cold and Ike may be running fast enough that it won’t affect it too much. If it gets there, there are also the mountains of Cuba and perhaps Hispaniola. So, Ike had some hurdles ahead…but I still think he may be a trouble maker. We’ll see. The National Hurricane Center Tropical Storm Ike Discussion is at the bottom.

Tropical Storm Josephine NHC Forecast Track 5 pm 0902

I’m blowing off Josephine for now because its so far away. But, it may end up getting into the ridge that is steering Ike and after getting drawn northwest by a trof in the Atlantic, start moving more westward.

TROPICAL STORM HANNA DISCUSSION NUMBER 24
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082008
500 PM EDT TUE SEP 02 2008

AN AIR FORCE RECONNAISSANCE AIRCRAFT CURRENTLY INVESTIGATING HANNA
CONFIRMS THAT THE SYSTEM HAS WEAKENED. THE PEAK FLIGHT-LEVEL WIND
AT 850 MB WAS 66 KT WHICH CORRESPONDS TO ABOUT 55 KT AT THE
SURFACE. HANNA WILL CONTINUE TO ENCOUNTER STRONG SHEAR FOR ANOTHER
12-24 HOURS WHICH SHOULD LIMIT STRENGTHENING IN THE SHORT TERM. BY
TOMORROW…GLOBAL MODELS FORECAST AN UPPER-LEVEL LOW TO CUT OFF
JUST WEST OF HANNA AND THEN DROP SOUTHWARD DURING THE NEXT FEW
DAYS. IF THIS EVOLUTION MATERIALIZES…AND ASSUMING HANNA IS ABLE
TO FIGHT OFF THE SHEAR…THE ENVIRONMENT WOULD GRADUALLY BECOME
MORE FAVORABLE FOR STRENGTHENING. THE OFFICIAL INTENSITY FORECAST
CALLS FOR HANNA TO REGAIN HURRICANE STRENGTH IN A DAY OR SO…IN
LINE WITH NEARLY ALL OF THE AVAILABLE INTENSITY MODELS.
HOWEVER…THE EVOLUTION OF THE LARGE-SCALE ENVIRONMENT OVER THE
NEXT DAY OR SO IS COMPLEX…WHICH RESULTS IN LOWER THAN NORMAL
CONFIDENCE IN THE INTENSITY FORECAST.

THE LAST FEW AIRCRAFT FIXES INDICATE THAT HANNA CONTINUES TO DRIFT
SOUTHEASTWARD WITH AN INITIAL MOTION ESTIMATE OF 150/02. TRACK
MODELS INSIST THAT HANNA WILL START ITS MUCH-ANTICIPATED TURN
TOWARD THE NORTHWEST SOON…AS A LARGE MID-LATITUDE TROUGH OVER THE
WESTERN ATLANTIC LIFTS NORTHWARD AND THE SUBTROPICAL RIDGE BUILDS
BACK IN. SUCH A TRACK WOULD TAKE THE CYCLONE NORTHWESTWARD THROUGH
THE CENTRAL AND NORTHWESTERN BAHAMAS DURING THE NEXT TWO DAYS.
HANNA IS THEN EXPECTED TO ACCELERATE AS IT MAKES ITS APPROACH TO
THE SOUTHEASTERN UNITED STATES. HOWEVER…UNTIL HANNA BEGINS A
MORE DEFINITIVE MOTION…IT WILL BE DIFFICULT TO NARROW THE
POTENTIAL IMPACT AREA. IN ADDITION…THE ANTICIPATED ANGLE OF
APPROACH TO THE SOUTHEAST UNITED STATES COAST MEANS THAN ONLY A
SMALL DEVIATION LEFT OR RIGHT OF THE TRACK WILL HAVE LARGE
IMPLICATIONS IN BOTH TIME AND LOCATION OF LANDFALL. IN FACT…THE
WIND SPEED PROBABILITY PRODUCT INCLUDED WITH THIS ADVISORY PACKAGE
SHOWS THAT THE CHANCES OF HURRICANE-FORCE WINDS ARE ABOUT EQUAL AT
EACH SPECIFIC LOCATION ALONG THE COAST FROM FLORIDA THROUGH THE
CAROLINAS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 02/2100Z 20.4N 72.7W 55 KT
12HR VT 03/0600Z 20.9N 73.1W 55 KT
24HR VT 03/1800Z 22.2N 74.0W 60 KT
36HR VT 04/0600Z 23.5N 75.5W 65 KT
48HR VT 04/1800Z 25.4N 77.2W 70 KT
72HR VT 05/1800Z 30.5N 80.5W 70 KT
96HR VT 06/1800Z 38.0N 78.0W 30 KT…INLAND
120HR VT 07/1800Z 47.0N 66.0W 25 KT…REMNANT LOW

$$
FORECASTER RHOME/KNABB

TROPICAL STORM IKE DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008
500 PM EDT TUE SEP 02 2008

AFTER LOOKING CONVECTIVELY ASYMMETRIC THIS MORNING…IKE HAS
WRAPPED A BAND OF DEEP CONVECTION MOST OF THE WAY AROUND THE CENTER
EXCEPT FOR SMALL BREAK OVER THE SOUTHERN QUADRANT. CONSEQUENTLY…
DVORAK T-NUMBERS HAVE RISEN TO 3.5 FROM BOTH TAFB AND SAB SO THE
INITIAL INTENSITY IS SET AT 55 KT BASED ON THE IMPROVED STRUCTURE.

IKE CONTINUES TO CHUG ALONG WITHIN THE TRADES AT 280/15. THE
MID-LEVEL HIGH THAT IS CENTERED NORTH-NORTHEAST OF IKE…STEERING
IT WESTWARD…IS EXPECTED TO BUILD INTO THE WEST ATLANTIC AND
RESULT IN VERY LITTLE POLEWARD MOTION IN THE COMING DAYS. ALTHOUGH
MOST OF THE MODEL GUIDANCE REMAINS CLUSTERED THROUGH DAY 5…THE
MOST NOTABLE CHANGE FROM THIS MORNING IS THE TRACK OF THE UKMET…
WHICH CURVES IKE TO THE NORTHWEST NEAR 65W IN RESPONSE TO A WEAKER
WEST ATLANTIC RIDGE. THE OFFICIAL FORECAST DISREGARDS THE UKMET AND
FOLLOWS A CONSENSUS OF THE OTHER MODELS…SHOWING A SLIGHT
SOUTH-OF-DUE-WEST MOTION IN ABOUT 48-72 HOURS. IT SHOULD BE NOTED
THAT THE EXACT STEERING REGIME AT DAY 5 REMAINS HIGHLY UNCERTAIN…
AND THE OFFICIAL FORECAST RECONCILES THIS BY SHOWING A MORE OR LESS
WESTWARD TRACK WITHIN THE GUIDANCE ENVELOPE.

THE INTENSITY GUIDANCE IS FAIRLY AGREEABLE IN THE SHORT-TERM…
BRINGING IKE TO A HURRICANE WITHIN ABOUT 12 HOURS. BEYOND
THAT…THE STATISTICAL-DYNAMICAL MODELS ARE A BIT RESERVED AND SHOW
PEAK INTENSITIES OF 70-80 KT BEFORE MODEST NORTHEASTERLY SHEAR SETS
IN BY 48 HOURS. THE HWRF MODEL IS WELL ABOVE ALL THE OTHER GUIDANCE
AND IN GENERAL ITS SOLUTION IS NOT COUNTED AT THIS TIME.
STILL…THERE APPEARS TO BE LITTLE REASON THAT INTENSIFICATION
SHOULD NOT OCCUR SO THE OFFICIAL INTENSITY FORECAST IS A LITTLE
HIGHER THAN THE SHIPS AND LGEM…BUT IN LINE WITH THE INTENSITY
CONSENSUS AND NEAR THE GFDL.

FORECAST POSITIONS AND MAX WINDS

INITIAL 02/2100Z 19.2N 46.3W 55 KT
12HR VT 03/0600Z 19.6N 48.6W 65 KT
24HR VT 03/1800Z 20.3N 51.8W 70 KT
36HR VT 04/0600Z 21.0N 55.0W 75 KT
48HR VT 04/1800Z 21.6N 57.8W 80 KT
72HR VT 05/1800Z 22.0N 63.5W 85 KT
96HR VT 06/1800Z 21.5N 69.5W 90 KT
120HR VT 07/1800Z 21.5N 75.0W 95 KT

$$
FORECASTER BERG/KNABB