Supercomputer Weather: Hurricane Alberto?
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Atlantic Hurricane Season 2006 Starts With Alberto
Report compiled by Alastair Thompson
The Atlantic Hurricane season for 2006 is expected to be one of the worst ever. Last year's season was in fact the worst ever to date, and will be hard to beat, however, so far 2006 is shaping up as expected.
Nine days into the season what is now Tropical Storm Alberto started to form in the Gulf of Mexico. Four days later 20,000 Florida residents have been ordered to evacuate a section of the Florida coast which is expected to bear the brunt of an 8-10 foot storm surge in advance of the hurricane – which according to the latest advisory is now not expected to be an actual hurricane on landfall in 18 hours.
However as Alberto has proven highly unpredictable thus far – strengthening when shear should have stopped it doing so, and advancing at a very uncertain pace for the coast – time will tell whether Alberto becomes a hurricane or not in the end. Either way Alberto has definitely got the United States attention.
Welcome to Atlantic Hurricane Season 2006.
WTNT41 KNHC 130838
TROPICAL STORM ALBERTO DISCUSSION NUMBER 13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012006
500 AM EDT TUE JUN 13 2006
WITH A SLUG OF DRY AIR OVERTAKING THE CENTER OF CIRCULATION... ALBERTO'S CHANCES OF BECOMING A HURRICANE ARE EVAPORATING. THERE IS NO DEEP CONVECTION NEAR THE CENTER AND THE CYCLONE IS TAKING ON A LESS-THAN-TROPICAL APPEARANCE ON SATELLITE IMAGERY. THE WIND FIELD HAS ALSO BROADENED CONSIDERABLY OVER THE PAST 12 HOURS OR SO. PEAK 850 MB FLIGHT-LEVEL WINDS FROM THE LAST RECONNAISSANCE FLIGHT WERE 64 KT...WHICH GIVEN THE RELATIVE LACK OF CONVECTION...WOULD CORRESPOND TO ABOUT 50 KT AT THE SURFACE. A QUIKSCAT PASS NEAR 0Z DID SHOW WINDS AS HIGH AS 55 KT...WHICH WILL BE THE ADVISORY INTENSITY FOR THIS PACKAGE. LITTLE CHANGE IN STRENGTH IS EXPECTED PRIOR TO LANDFALL.
THE INITIAL MOTION IS 035/8. AS A MID-LATITUDE SHORT WAVE MOVES EASTWARD OFF THE ATLANTIC SEABOARD...BUILDING HEIGHTS BEHIND THE TROUGH ARE EXPECTED TO NUDGE THE TRACK A LITTLE TO THE LEFT BEFORE ALBERTO GETS PICKED UP BY THE NEXT SHORT WAVE. MODEL GUIDANCE IS IN GOOD AGREEMENT IN KEEPING THE CENTER OVER LAND FOR MUCH OF THE NEXT 36 HOURS. AFTER THAT...ALBERTO SHOULD ACCELERATE IN THE WESTERLIES AS AN EXTRATROPICAL CYCLONE. THE OFFICIAL FORECAST IS SIGNIFICANTLY FASTER THAN THE PREVIOUS ADVISORY AFTER 72 HOURS...AND IS IN ROUGH AGREEMENT WITH THE DYNAMICAL MODEL CONSENSUS.
SINCE THE BROAD CIRCULATION OF ALBERTO WILL DECAY ONLY SLOWLY AFTER LANDFALL...THERE IS SOME POSSIBILITY OF ONSHORE WINDS TO TROPICAL STORM FORCE NORTH OF THE PRESENT WARNING AREA ON THE ATLANTIC COAST. THE TROPICAL STORM WARNING HAS THEREFORE BEEN EXTENDED NORTHWARD.
FORECAST POSITIONS AND MAX WINDS
INITIAL 13/0900Z 29.2N 84.2W 55 KT
12HR VT 13/1800Z 30.3N 83.4W 45 KT...INLAND
24HR VT 14/0600Z 32.1N 81.9W 35 KT...EXTRATROPICAL
36HR VT 14/1800Z 34.4N 78.9W 30 KT...EXTRATROPICAL
48HR VT 15/0600Z 37.0N 73.5W 35 KT...EXTRATROPICAL
72HR VT 16/0600Z 43.5N 62.0W 40 KT...EXTRATROPICAL
96HR VT 17/0600Z 50.5N 48.5W 40 KT...EXTRATROPICAL
120HR VT 18/0600Z 55.0N 25.0W 40 KT...EXTRATROPICAL
INITIAL 13/0900Z 29.2N 84.2W 55 KT 12HR VT 13/1800Z 30.3N 83.4W 45 KT...INLAND 24HR VT 14/0600Z 32.1N 81.9W 35 KT...EXTRATROPICAL 36HR VT 14/1800Z 34.4N 78.9W 30 KT...EXTRATROPICAL 48HR VT 15/0600Z 37.0N 73.5W 35 KT...EXTRATROPICAL 72HR VT 16/0600Z 43.5N 62.0W 40 KT...EXTRATROPICAL 96HR VT 17/0600Z 50.5N 48.5W 40 KT...EXTRATROPICAL 120HR VT 18/0600Z 55.0N 25.0W 40 KT...EXTRATROPICAL
SUPERCOMPUTER GFS MODEL FORECAST OF ALBERTO'S LANDFALL
+12 Hours (Midday 13
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