000 WTNT43 KNHC 140859 TCDAT3 HURRICANE PAULA DISCUSSION NUMBER 12 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL182010 400 AM CDT THU OCT 14 2010 THE CLOUD PATTERN OF PAULA HAS CONTINUED TO BECOME LESS ORGANIZED THIS MORNING AS THE HURRICANE IS ENCOUNTERING 30 KT OF SOUTHWESTERLY VERTICAL WIND SHEAR. HOWEVER...RADAR DATA FROM CUBA SHOWS THAT THE EYE AND EYEWALL ARE STILL INTACT FOR NOW. AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT JUST REPORTED THE CENTRAL PRESSURE HAS RISEN TO 999 MB...WITH 700 MB FLIGHT-LEVEL WINDS OF 72 KT. BASED ON THIS...THE INITIAL INTENSITY IS REDUCED TO 65 KT. A BROAD MID/UPPER-LEVEL TROUGH OVER THE EASTERN UNITED STATES IS TRYING TO STEER PAULA IN A GENERALLY EAST-NORTHEASTERLY DIRECTION. HOWEVER...A LOW-LEVEL RIDGE OVER THE WESTERN ATLANTIC IS BLOCKING THIS MOVEMENT WITH THE RESULT BEING A SLOW INITIAL MOTION OF 050/4. THE DYNAMICAL MODELS FORECAST THE MID/UPPER-LEVEL WESTERLY FLOW FLOW TO INCREASE WHILE HIGH PRESSURE BUILDS IN AT THE LOW LEVELS NORTH AND WEST OF PAULA. THIS EVOLUTION IS LIKELY TO CAUSE PAULA TO SHEAR APART...WITH THE LOW-LEVEL REMNANTS TURNING SOUTHEASTWARD AND THEN POSSIBLY SOUTHWESTWARD. WHILE THE GUIDANCE AGREES WITH THIS SCENARIO...THERE IS A LARGE SPREAD ON WHEN AND WHERE THIS DECOUPLING WILL OCCUR. THE ECMWF IS THE FARTHEST WEST...WHILE THE GFDL IS THE FARTHEST EAST. THE NEW FORECAST TRACK LIES BETWEEN THESE EXTREMES CLOSE TO THE VARIOUS CONSENSUS MODELS...AND IS ALMOST IDENTICAL TO THE PREVIOUS FORECAST SHEAR...DRY AIR ENTRAINMENT...AND LAND INTERACTION SHOULD CAUSE PAULA TO WEAKEN SIGNIFICANTLY DURING THE NEXT 48 HR. THE INTENSITY FORECAST CALLS FOR THE SYSTEM TO WEAKEN TO A TROPICAL STORM LATER TODAY...A TROPICAL DEPRESSION IN ABOUT 36 HR...AND TO A REMNANT LOW BY 48 HR. THERE IS A POSSIBILITY THAT THE CYCLONE COULD WEAKEN FASTER THAN CURRENTLY FORECAST ONCE IT SHEARS APART. FORECAST POSITIONS AND MAX WINDS INITIAL 14/0900Z 22.3N 84.9W 65 KT 12HR VT 14/1800Z 22.6N 84.0W 60 KT...INLAND 24HR VT 15/0600Z 22.9N 82.5W 45 KT...INLAND 36HR VT 15/1800Z 22.9N 81.1W 30 KT...INLAND 48HR VT 16/0600Z 22.3N 80.1W 25 KT...POST-TROP/REMNT LOW 72HR VT 17/0600Z 21.5N 79.5W 20 KT...POST-TROP/REMNT LOW 96HR VT 18/0600Z...DISSIPATED $$ FORECASTER BEVEN