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| #64371 (Received by flhurricane at: 4:17 AM 03.Jan.2006) TCDAT5 TROPICAL STORM ZETA DISCUSSION NUMBER 16 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 4 AM EST TUE JAN 03 2006 AT THE CIRRUS LEVEL...ZETA IS NOW EXHIBITING OUTFLOW IN EVERY QUADRANT WHILE IT MAINTAINS CONVECTION WITH TOPS NEAR -70C. HOWEVER...THE CENTER IS STILL NEAR THE SOUTHWEST EDGE OF THE DEEP CONVECTION AS SOME SOUTHWESTERLY FLOW UNDERCUTS THE DEVELOPING OUTFLOW. DVORAK CI NUMBERS FROM TAFB AND SAB ARE T3.5...OR 55 KT...AND AS NOTED IN THE PREVIOUS DISCUSSION THE QUIKSCAT PASS FROM 2039Z LAST EVENING SUPPORTED WINDS THIS STRONG AS WELL. CONSEQUENTLY THE ADVISORY INTENSITY IS INCREASED TO 55 KT. WATER VAPOR IMAGERY SHOWS A MID- TO UPPER-LEVEL TROUGH APPROACHING ZETA FROM THE WEST...BUT THE GLOBAL MODELS ARE QUITE CONSISTENT IN FORECASTING THIS TROUGH TO SPLIT AND DROP SOUTH OF ZETA. IF THIS OCCURS...THE WESTERLY SHEAR OVER ZETA COULD LESSEN SUBSTANTIALLY OVER THE NEXT 12-24 HOURS AND THE GFDL'S FORECAST OF A HURRICANE DOESN'T LOOK SO UNREASONABLE ANY MORE. NO KNOWN HURRICANE HAS EVER FORMED DURING THE MONTH OF JANUARY. I WON'T GO THAT FAR WITH THE OFFICIAL FORECAST...BUT WILL HOLD THE INTENSITY STEADY FOR THE NEXT DAY OR SO. AFTER THE UPPER TROUGH MOVES THROUGH I EXPECT THE SHEAR TO INCREASE AGAIN...AND EVEN THE GFDL WEAKENS ZETA SUBSTANTIALLY BY DAY 4. THE INITIAL MOTION IS 245/2. ZETA REMAINS SOUTH OF A WEAK MID- TO LOWER-LEVEL RIDGE...AND THIS RIDGE SHOULD REMAIN IN PLACE FOR THE NEXT COUPLE OF DAYS. AFTER THAT...MUCH OF THE MODEL GUIDANCE SUGGESTS THAT ZETA MAY LIFT NORTHWARD AHEAD OF THE LARGE LOW CURRENTLY OVER THE EASTERN UNITED STATES...BUT ONCE AGAIN THIS TROUGH IS FORECAST TO SPLIT AND HENCE MAY LEAVE ZETA...OR ITS REMNANTS...BEHIND. THE OFFICIAL FORECAST IS SHIFTED A LITTLE TO THE RIGHT OF THE PREVIOUS TRACK TO BE IN BETTER AGREEMENT WITH THE GFDL. FORECASTER FRANKLIN FORECAST POSITIONS AND MAX WINDS INITIAL 03/0900Z 23.3N 41.3W 55 KT 12HR VT 03/1800Z 23.3N 41.7W 55 KT 24HR VT 04/0600Z 23.3N 42.9W 55 KT 36HR VT 04/1800Z 23.5N 43.9W 45 KT 48HR VT 05/0600Z 24.3N 44.8W 40 KT 72HR VT 06/0600Z 27.0N 45.5W 30 KT 96HR VT 07/0600Z 27.5N 45.5W 25 KT...REMNANT LOW 120HR VT 08/0600Z...DISSIPATED |
