Tropical Storm FABIAN
ZCZC MIATCDAT5 ALL TTAA00 KNHC DDHHMM TROPICAL STORM FABIAN DISCUSSION NUMBER 8 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 AM EDT FRI AUG 29 2003 THE CLOUD PATTERN CONSISTS OF A CYCLONIC CURVED BAND THAT WRAPS AROUND THE CENTER OF CIRCULATION. THERE IS FAIR OUTFLOW AT THIS TIME. AN SSMI PASS AT 0930Z SHOWED A RING OF CONVECTION ASSOCIATED WITH THE CENTER OF FABIAN. T-NUMBERS FROM ALL AGENCIES ARE 3.5 ON THE DVORAK SCALE SUGGESTING WINDS OF 55 KNOTS. BECAUSE THE CLOUD PATTERN IS STILL RAGGED...INITIAL INTENSITY IS KEPT AT 50 KNOTS. SHIPS MODEL INTENSIFIES FABIAN ASSUMING THAT THERE WILL BE LOW SHEAR AND HIGHER SSTS AHEAD OF THE TROPICAL CYCLONE. SHIPS DEPENDS ON THE GFS MODEL WHICH IS FORECASTING LOW SHEAR ALONG THE PATH OF THE CYCLONE. HOWEVER...WATER VAPOR IMAGES STILL SHOW A BAND OF STRONG UPPER-LEVEL WESTERLIES ASSOCIATED WITH AN UPPER TROUGH AHEAD OF THE CYCLONE. THE GFDL BRINGS FABIAN TO 100 KNOTS BY THE END OF THE FORECAST PERIOD. DUE TO THE PERSISTENT STRONG UPPER-LEVEL WESTERLY WINDS NORTH OF THE LESSER ANTILLES...THE OFFICIAL FORECAST CALLS FOR A MODEST STRENGTHENING. FABIAN CONTINUES TO MOVE WESTWARD...A LITTLE SLOWER...AT ABOUT 14 KNOTS AROUND THE PERIPHERY OF THE SUBTROPICAL RIDGE. STEERING CURRENTS ARE FORECAST TO WEAKEN RESULTING IN A GRADUAL DECREASE IN FORWARD SPEED. A HIGH PRESSURE SYSTEM CURRENTLY CENTERED JUST EAST OF THE U.S. EAST COAST IS FORECAST TO MOVE EASTWARD. THIS WOULD ALLOW FABIAN TO TURN MORE TO THE WEST-NORTHWEST IN THE LONG RANGE. THIS IS CONSISTENT WITH TRACK GUIDANCE WHICH MOVES FABIAN WELL TO THE NORTH OF THE LEEWARD ISLANDS IN 4 TO 5 DAYS. FORECASTER AVILA FORECAST POSITIONS AND MAX WINDS INITIAL 29/1500Z 15.5N 43.7W 50 KT 12HR VT 30/0000Z 15.8N 46.0W 60 KT 24HR VT 30/1200Z 16.5N 48.5W 65 KT 36HR VT 31/0000Z 17.5N 51.0W 70 KT 48HR VT 31/1200Z 18.5N 53.5W 75 KT 72HR VT 01/1200Z 19.5N 57.5W 80 KT 96HR VT 02/1200Z 20.5N 60.5W 80 KT 120HR VT 03/1200Z 22.0N 64.0W 80 KT NNNN