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
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.
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.
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
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.
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 may become Hurricane Hanna again and will be a wind and
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 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
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
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