000 AXNT20 KNHC 021805 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED MAY 02 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS... WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 7N11W 4N20W 5N34W AND INTO NE BRAZIL NEAR 2S45W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 3S-12N E OF 18W. SCATTERED MODERATE IS WITHIN 60NM EITHER SIDE OF THE AXIS BETWEEN 24W-30W. THE TROUGH THAT WAS EMBEDDED IN THE ITCZ NEAR 30W HAS BECOME VERY ELONGATED AND IS DIFFICULT TO DISCERN...AND CONVECTION HAS ALSO DIMINISHED AROUND THIS FEATURE. HAVE THUS OPTED TO LEAVE THE TROUGH OFF THE MAP FOR NOW. ...DISCUSSION... GULF OF MEXICO... THE W PORTION OF AN ATLC SFC RIDGE EXTENDS INTO THE GULF THIS AFTERNOON WHICH IS PRODUCING LIGHT TO MODERATE RETURN FLOW ACROSS THE AREA...STRONGEST IN THE WRN PORTION WHERE THE GRADIENT IS A LITTLE TIGHTER IN RESPONSE TO LOWER PRESSURE OVER MEXICO. LITTLE CLOUD COVER/FAIR WEATHER DOMINATES MUCH OF THE BASIN...THOUGH THE MOBILE RADAR IS SHOWING ISOLATED SHOWER/TSTMS MOVING N IN THE N GULF. THIS SEEMS TO BE ASSOCIATED WITH THE LOW LEVEL CONFLUENCE NOTED FROM 26N-30N BETWEEN 86W-89W. A BAND OF UPPER MOISTURE IS SEEN IN WV IMAGERY BETWEEN NE MEXICO AND LOUISIANA...SUPPORTED BY DIFFLUENCE BETWEEN THE UPPER RIDGE EXTENDING INTO THE WRN GULF FROM THE EPAC AND THE UPPER LOW OVER SE KANSAS. UPPER TROUGHING AND FAIRLY DRY AIR IS OVER THE ERN GULF. LIGHT TO MODERATE RETURN FLOW CONTINUES THROUGH THE END OF THE WORKWEEK. THIS LOW LEVEL MOISTURE ALONG WITH THE DYNAMICS AHEAD OF THE MID/UPPER LOW MOVING E FROM NEW MEXICO WILL SUPPORT SHOWER/TSTMS ACTIVITY IN THE NW GULF DURING THU. CARIBBEAN SEA... MODERATE TO FRESH TRADE FLOW WITH TYPICAL LOW LEVEL MOISTURE PATCHES/ISOLATED SHOWERS DOMINATE MUCH OF THE BASIN THIS AFTERNOON. ADDITIONAL LOW LEVEL CONFLUENCE AND UPPER DIFFLUENCE ARE ALLOWING THESE SHOWERS TO GET A LITTLE DEEPER IN THE NW CARIB BETWEEN ERN HONDURAS AND ERN CUBA. SCATTERED MODERATE CONVECTION LIKELY TIED TO THE ITCZ IS IN THE SW CARIB S OF 13N BETWEEN 76W-82W. UPPER MOISTURE OVER THIS AND OTHER EPAC ITCZ CONVECTION IS SPREADING NE BETWEEN CENTRAL AMERICA AND THE SE BAHAMAS...WITH UPPER SW FLOW. UPPER FLOW BENDS MORE WLY IN THE ERN CARIB AROUND RIDGING. SIMILAR TRADE WIND REGIME EXPECTED OVER THE NEXT COUPLE OF DAYS. ATLANTIC... A PAIR OF SFC TROUGHS EMBEDDED IN THE WRN PORTION OF HIGH PRES DOMINATE THE WRN ATLC WEATHER TODAY. THE FIRST IS OFFSHORE FLORIDA ALONG 31N78W 26N79W. ASSOCATED SCATTERED SHOWERS/TSTMS ARE FROM 27N-31N BETWEEN 78W-80W. THE OTHER IS EXTENDING THROUGH THE SE BAHAMAS ALONG 26N73W 20N74W. SCATTERED SHOWERS/TSTMS ASSOCIATED WITH THIS TROUGH ARE AFFECTING THE TURKS AND CAICOS...SE BAHAMAS...AND ADJACENT WATERS FROM 20N-27W BETWEEN 68W-76W. THE GFS MODEL HAS BEEN KEYING IN ON THIS TROUGH...AND FORMS A CLOSED LOW NE OF THE BAHAMAS BY TOMORROW EVENING. SEE OFFSHORE WATERS FORECAST UNDER AWIPS HEADER MIAOFFNT3 FOR MORE DETAILS. THE PAIR OF TROUGHS IN THE WRN ATLC ARE BEING SUPPORTED BY LIFT AHEAD OF THE UPPER TROUGH EXTENDING S THROUGH THE GULF OF MEXICO. ANOTHER REMNANT SFC TROUGH IS ALONG 31N51W 28N58W...GENERATING ISOLATED SHOWERS FROM 27N-31W BETWEEN 50W-59W. THE REMAINDER OF THE ATLC DISCUSSION AREA IS DOMINATED BY HIGH PRES...S OF A 1029MB CENTER S OF THE AZORES NEAR 33N31W. ANOTHER WEAK 1022MB HIGH PRES CENTER IS NEAR 30N63W...BUT IS EXPECTED TO GET ABSORBED INTO THE AZORES HIGH THROUGH THU. $$ WILLIS