Unpredictable

TROPICAL DEPRESSION TWENTY ATTAINED TROPICAL STORM STATUS JUST OFF THE EAST COAST OF THE YUCATAN PENINSULA. THIS IS BASED ON 850 MB FLIGHT LEVEL WINDS OF 50 KT WITHIN A BAND OF VERY DEEP CONVECTION TO THE SOUTHEAST OF THE BROAD CIRCULATION CENTER... WHICH IS CHARACTERIZED BY A FAIRLY LARGE AREA OF WEAK WINDS.

THE FLIGHT LEVEL WINDS CORRESPOND TO ABOUT 40 KT AT THE SURFACE.

THE CENTRAL PRESSURE FELL TO ABOUT 1003 MB. SATELLITE IMAGERY INDICATES THE CENTER IS NOW MAKING LANDFALL SOUTH OF TULUM... SO THE ADVISORY INTENSITY REMAINS 40 KT... BUT STAN IS EXPECTED TO WEAKEN WHILE SPENDING ALMOST THE NEXT 24 HOURS OVER LAND.

CONDITIONS ARE STILL EXPECTED TO BE CONDUCIVE FOR RESTRENGTHENING OVER THE SOUTHWESTERN GULF OF MEXICO... AND THE OFFICIAL FORECAST ANTICIPATES A HURRICANE BY 72 HOURS... IN ACCORDANCE WITH THE SHIPS MODEL AFTER ACCOUNTING FOR INTERACTION WITH LAND IN THE SHORT TERM.

STAN CONTINUES MOVING WEST-NORTHWESTWARD AT ABOUT 5 KT... ALTHOUGH THIS IS A LITTLE UNCERTAIN GIVEN THE DIFFICULTY IN SPECIFYING THE EXACT CENTER OF THE BROAD CIRCULATION.

THE NEW OFFICIAL FORECAST IS VERY SIMILAR TO THE PREVIOUS ADVISORY... ONLY A LITTLE SLOWER LATE IN THE PERIOD DUE TO A LACK OF MODELS ACTUALLY SHOWING FINAL LANDFALL ON THE GULF COAST OF MEXICO. THIS SOLUTION IS FOLLOWED FOR CONTINUITY AND SINCE THE VARIOUS MODEL SOLUTIONS BEYOND 48 HOURS ARE SO DIVERSE.

THERE WOULD APPEAR TO BE ENOUGH RIDGING OVER THE GULF OF MEXICO TO FORCE STAN WESTWARD ACROSS THE ENTIRE BAY OF CAMPECHE.

FORECASTER KNABB

FORECAST POSITIONS AND MAX WINDS

INITIAL 02/0900Z 19.6N 87.5W 40 KT

12HR VT 02/1800Z 20.1N 88.9W 30 KT...INLAND

24HR VT 03/0600Z 20.7N 90.9W 35 KT

36HR VT 03/1800Z 21.0N 92.9W 45 KT

48HR VT 04/0600Z 20.9N 94.5W 55 KT

72HR VT 05/0600Z 20.5N 96.0W 70 KT

96HR VT 06/0600Z 20.0N 97.5W 30 KT...INLAND

120HR VT 07/0600Z...DISSIPATED

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