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| #63607 (Received by flhurricane at: 10:46 PM 30.Dec.2005) TCDAT5 TROPICAL STORM ZETA DISCUSSION NUMBER 2 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 4 PM EST FRI DEC 30 2005 DVORAK CLASSIFICATIONS AT 18Z WERE T3.0...OR 45 KT...FROM TAFB AND SAB...WHILE AFWA GAVE ZETA A SUBTROPICAL T2.5 CLASSIFICATION. BASED ON THESE CLASSIFICATIONS...THE INITIAL INTENSITY IS HELD AT 45 KT. THE WELL-DEFINED BANDING STRUCTURES SEEN THIS MORNING HAVE ALREADY BECOME RAGGED...AND WATER VAPOR IMAGERY SHOWS DRY WESTERLIES BEGINNING TO IMPINGE ON THE WESTERN PORTION OF THE CIRCULATION. WHILE THERE COULD BE BRIEF ADDITIONAL DEVELOPMENT DURING TONIGHT'S CONVECTIVE MAXIMUM...STRONG WESTERLIES ARE NOT FAR FROM THE CYCLONE AND SHOULD OVERTAKE ZETA WITHIN 24 HOURS. THE INITIAL MOTION IS 310/6. THERE HAS BEEN LITTLE CHANGE TO THE FORECAST REASONING. ZETA IS STILL MOVING AROUND A MID-LEVEL LOW TO ITS SOUTHWEST...BUT THIS FEATURE IS EXPECTED TO WEAKEN AS THE WESTERLIES MOVE IN DURING THE NEXT 12-24 HOURS. ASSUMING ZETA WEAKENS IN RESPONSE TO THE INCREASE IN SHEAR...IT SHOULD THEN TURN WESTWARD WITH THE LOW-LEVEL FLOW. THE OFFICIAL FORECAST IS A BLEND OF THE MEDIUM AND SHALLOW BAM MODELS...AND THE 12Z GFDL. THE HISTORICAL RECORD SHOWS THAT ALICE OFFICIALLY BECAME A TROPICAL STORM AT 1200 UTC 30 DECEMBER 1954. MY WORKING BEST TRACK FOR ZETA CURRENTLY SHOWS STORM STATUS BEGINNING AT 1200 UTC THIS MORNING... WHICH TENTATIVELY ALLOWS ZETA TO TIE ALICE FOR THE LATEST FORMING TROPICAL STORM IN THE ATLANTIC BASIN. HOWEVER...A CASE CAN BE MADE FOR CONSIDERING ZETA A TROPICAL STORM AS EARLY AS 0600 UTC THIS MORNING. WE'LL HAVE TO WAIT FOR THE FINAL ANALYSIS OF ZETA'S TRACK TO SEE EXACTLY WHERE ITS FORMATION FALLS RELATIVE TO ALICE'S. ALTHOUGH THE ATMOSPHERE SEEMS TO WANT TO DEVELOP TROPICAL STORMS AD NAUSEAM...THE CALENDAR WILL SHORTLY PUT AN END TO THE USE OF THE GREEK ALPHABET TO NAME THEM. FORECASTER FRANKLIN FORECAST POSITIONS AND MAX WINDS INITIAL 30/2100Z 25.3N 37.3W 45 KT 12HR VT 31/0600Z 25.6N 38.0W 45 KT 24HR VT 31/1800Z 25.8N 39.0W 35 KT 36HR VT 01/0600Z 26.0N 40.4W 25 KT...DISSIPATING 48HR VT 01/1800Z 26.0N 42.0W 25 KT...REMNANT LOW 72HR VT 02/1800Z...DISSIPATED |
