000 AXNT20 KNHC 020600 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT MON APR 2 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0530 UTC. ...THE ITCZ... ITCZ IS CENTERED ALONG 5N10W 2N20W EQ30W AND INTO NE BRAZIL NEAR 3S44W. ANOTHER IMPRESSIVE AREA OF NUMEROUS MODERATE TO STRONG CONVECTION IS AFFECTING AFRICA AND ADJACENT ATLC WATERS OF THE TONIGHT...FROM 1S-12N BETWEEN THE PRIME MERIDIAN AND 3W. ISOLATED MODERATE IS WITHIN 90NM N/30NM S OF THE AXIS BETWEEN 9W-15W AND WITHIN 90NM EITHER SIDE BETWEEN 28W-31W. SCATTERED MODERATE/ISOLATED STRONG IS FROM 3S-3N BETWEEN 35W-48W. ...DISCUSSION... GULF OF MEXICO... NUMEROUS SHOWERS AND TSTMS HAVE FIRED UP AGAIN ALONG THE ERN SLOPES OF THE SIERRA MADRES WITH MOIST UPSLOPE SE FLOW AND SUBTLE DIFFLUENT FLOW ALOFT. SOME OF THESE ARE SPILLING INTO THE WRN GULF JUST SE OF BROWNSVILLE FROM 23N-26N W OF 96W. UPPER MOISTURE/CIRRUS OVER THE CONVECTION IS SPREADING E OVER MUCH OF THE GULF WITH UPPER WSW FLOW BEHIND RIDGING EXTENDING NNE THROUGH FLORIDA TO THE COAST OF NEW ENGLAND. OTHERWISE CONDITIONS ARE FAIRLY QUIET WITH THE WRN PORTION OF AN ATLC SFC RIDGE OVER THE AREA...AND 5-15 KT RETURN FLOW DOMINATING. RIDGING WILL CONTINUE OVER THE GULF THROUGH TUE NIGHT AND THEN WEAKEN INTO WED IN ADVANCE OF A WEAK COLD FRONT TO PUSH INTO THE N CENTRAL WATERS. POTENTIAL FOR SHOWERS/TSTMS IN THE NW GULF WILL CONTINUE OVER THE NEXT DAY OR SO WITH MOIST SE FLOW. CARIBBEAN SEA... A 1026 MB SFC HIGH SITUATED NORTH OF THE AREA IS PRODUCING MODERATE TO STRONG TRADE WINDS ACROSS THE BASIN. THESE WINDS ARE DRIVING PATCHES OF LOW/MID LEVEL CLOUDS WITH ISOLATED SHOWERS ACROSS THE SEA...MOST CONCENTRATED FROM 13N-16N E OF 73W WHICH SEEMS TO BE ASSOCIATED WITH AN OLD FRONTAL ZONE. SIMILAR MOISTURE IS POOLING UP ALONG THE COASTAL PLAINS OF CENTRAL AMERICA. BROAD RIDGING CONTINUES TO DOMINATE THE MID AND UPPER LEVEL PATTERN FROM ITS ORIGIN IN THE TROPICAL ATLC. THIS IS ADVECTING SCATTERED PATCHES OF CIRRUS ENE THROUGH THE BASIN ESPECIALLY S OF 15N. DRY AIR AND MODERATE TO STRONG SUBSIDENCE ALOFT ARE FOUND OVER MUCH OF THE REMAINDER OF THE CARIB. ATLC HIGH PRES WILL MAINTAIN BRISK NE WINDS THROUGH TUE WITH WINDS THEN DIMINISHING THU AND FRI. ATLANTIC OCEAN... A VERTICALLY STACKED RIDGE/TROUGH/RIDGE PATTERN EXISTS ACROSS THE ATLC DISCUSSION AREA. A 1026 SFC HIGH NEAR 31N70W DOMINATES THE WRN ATLC BEHIND THE OLD BACKDOOR COLD FRONT THAT ENTERS THE AREA NEAR 32N33W AND CONTINUES SW TO 21N41W WHERE IT BECOMES A DISSIPATING STATIONARY FRONT TO 15N54W. SCATTERED SHOWERS ANTICIPATED IN THE BROKEN LOW TO MID CLOUD FIELD SEEN WITHIN 90 NM E OF THE FRONT. COLD AIR ADVECTION PATTERN EVIDENT BEHIND THE FRONT WITH SCATTERED TO BROKEN...CELLULAR STRATOCUMULUS NOTED OVER MUCH OF THE W AND CENTRAL ATLC N OF 19N. THE LARGE NLY SWELL THIS FRONTAL SYSTEM WAS RESPONSIBLE FOR LED TO THE ISSUANCE OF A HIGH SURF ADVISORY FOR NORTH EXPOSED BEACHES IN PUERTO RICO...SEE STATEMENTS FROM WFO SAN JUAN FOR MORE INFO. THE SWELL IS EXPECTED TO SUBSIDE SLOWLY THROUGH MIDWEEK. THE REMAINDER OF THE E ATLC IS DOMINATED BY THE SRN PERIPHERY OF A SFC HIGH PRES LOCATED WELL N OF THE AREA. THIS FEATURE IS PRODUCING ABUNDANT 10-20 KT E/NE WINDS AND FAIR WEATHER E OF 30W. THE RIDGING OVER THE WRN ATLC WILL SHIFT S WHILE WEAKENING OVER THE NEXT COUPLE OF DAYS. A COLD FRONT WILL PUSH OFF THE SE U.S. COAST LATE WED INTO THU BRINGING SHOWER POTENTIAL AND MODERATELY INCREASING WINDS/SEAS FOR THE AREA BETWEEN FLORIDA AND BERMUDA. THE FRONT IN THE E/CENTRAL ATLC WILL SLOWLY WEAKEN WHILE THE SRN PERIPHERY OF HIGH PRES CONTINUES TO DOMINATE THE FAR E ATLC. $$ WILLIS