for a more recent update on Ike & Hanna, CLICK HERE
For a remnant of Gustav Radar Loop and a Tropical Storm Hanna Radar Loop, CLICK HERE.
Basically nothing has changed from the last posting. Ike is still a very strong
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
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.
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
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.
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
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
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 $$