000 WTNT41 KNHC 011444 TCDAT1 TROPICAL STORM FELIX DISCUSSION NUMBER 4 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062007 1100 AM EDT SAT SEP 01 2007 RADAR IMAGES FROM MARTINIQUE INDICATED THE CENTER PASSED VERY NEAR GRENADA OVERNIGHT...WITH THE ISLAND OBSERVING 1005 MB BEFORE THE WEATHER STATION STOPPED REPORTING. SINCE THAT TIME...SATELLITE AND RADAR DATA INDICATE THAT FELIX IS FORMING A SMALL INNER CORE WITH TIGHTLY-WOUND BANDS AROUND THE CENTER. IN FACT...AN AIR FORCE PLANE JUST MADE IT TO THE CENTER AND REPORTED FLIGHT LEVEL WINDS OF 69 KT...CORRESPONDING TO ABOUT 55 KT AT THE SURFACE...AND 55 KT WILL BE USED AS THE INITIAL INTENSITY. ALL ATMOSPHERIC AND OCEANIC PARAMETERS SUPPORT A CONTINUED STRENGTHENING OF THE STORM. WITH SUCH A FAVORABLE ENVIRONMENT...IT IS LIKELY THAT FELIX WILL BECOME A POWERFUL HURRICANE BY THE TIME IT REACHES THE NORTHWESTERN CARIBBEAN SEA. THE GFDL/HWRF ONLY SLOWLY INTENSIFY THE SYSTEM...BUT THE SHIPS/LGEM MODELS SUGGEST THIS STORM COULD BE A MAJOR HURRICANE IN ABOUT 3 DAYS. THE NHC INTENSITY FORECAST GOES WITH THE LATTER SCENARIO AND IS JUST A LITTLE LOWER THAN THE STATISTICAL MODELS FOR THIS FORECAST PACKAGE. FELIX HAS BEEN MOVING BASICALLY TO WEST FOR THE PAST 6-12 HOURS AND MY INITIAL MOTION ESTIMATE IS 270/16. A STRONG RIDGE IS FORECAST TO STEER THE STORM A LITTLE NORTH OF DUE WESTWARD FOR THE NEXT FEW DAYS. TRACK GUIDANCE IS IN GOOD AGREEMENT ON THIS SCENARIO. BEYOND 3 DAYS...THERE IS A QUESTION OF HOW MUCH RIDGING WILL BE PRESENT IN THE GULF OF MEXICO. A FEW MODELS HAVE ENOUGH OF A WEAKNESS IN THE RIDGE TO FORCE A WEST-NORTHWEST OR NORTHWEST MOTION NEAR THE END OF THE PERIOD. HOWEVER...THE RELIABLE GFS/ECMWF ARE KEEPING A STRONG RIDGE. THE OFFICIAL FORECAST IS A LITTLE SOUTH OF THE PREVIOUS ONE DUE TO THE WESTWARD MOTION EARLY ON...BUT THEN IS VERY CLOSE TO THE PREVIOUS FORECAST BY THE END OF THE PERIOD. FORECAST POSITIONS AND MAX WINDS INITIAL 01/1500Z 12.3N 63.6W 55 KT 12HR VT 02/0000Z 12.8N 66.1W 60 KT 24HR VT 02/1200Z 13.4N 69.4W 65 KT 36HR VT 03/0000Z 14.1N 72.9W 70 KT 48HR VT 03/1200Z 14.8N 76.2W 80 KT 72HR VT 04/1200Z 16.0N 82.0W 90 KT 96HR VT 05/1200Z 17.0N 87.0W 100 KT 120HR VT 06/1200Z 18.5N 91.5W 55 KT...INLAND $$ FORECASTER BLAKE/AVILA