000 AXNT20 KNHC 021041 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1030 UTC. ...THE ITCZ... ITCZ IS CENTERED ALONG 6N10W 2N20W EQ35W AND INTO NE BRAZIL NEAR 3S44W. IMPRESSIVE AREA OF NUMEROUS MODERATE TO STRONG CONVECTION IS AFFECTING AFRICA AND ADJACENT ATLC WATERS FROM 1S-7N BETWEEN THE 1W-9W. ISOLATED MODERATE IS WITHIN 120NM N OF AXIS BETWEEN 12W-23W. SCATTERED MODERATE/ISOLATED STRONG IS FROM 2S-3N BETWEEN 32W-44W. ...DISCUSSION... GULF OF MEXICO... CLUSTER OF MODERATE CONVECTION PUSHING E FROM THE COAST OF MEXICO IS PRODUCING NUMEROUS SHOWERS AND TSTMS IN THE WRN GULF FROM 22N-26N W OF 94W. BOTH LOW LEVEL REFLECTIVITY AND STORM RELATIVE VELOCITY DATA FROM THE BROWNSVILLE RADAR SHOW SOME MESO CYCLONIC TURNING IN THIS REGION AS WELL. THIS ACTIVITY IS ASSOCIATED WITH MID TO UPPER DYNAMICS AHEAD OF THE TROUGHING EXTENDING S THROUGH BAJA...ALONG WITH MOIST LOW LEVEL SE FLOW. UPPER MOISTURE/CIRRUS OVER THE CONVECTION IS SPREADING E OVER MUCH OF THE GULF WITH THE DOMINATING W TO WSW UPPER FLOW. OTHERWISE CONDITIONS ACROSS THE GULF 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 LOW LEVEL SE FLOW AND THE MID TO UPPER TROUGHING W OF THE AREA. 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 78W 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 OVER THE CARIB FROM ITS ORIGIN IN THE TROPICAL ATLC. THIS IS ADVECTING SCATTERED PATCHES OF CIRRUS ENE THROUGH THE BASIN ESPECIALLY S OF 14N . 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 30N68W DOMINATES THE WRN ATLC BEHIND THE OLD BACKDOOR COLD FRONT THAT ENTERS THE AREA NEAR 32N32W AND CONTINUES SW TO 20N41W WHERE IT BECOMES A DISSIPATING STATIONARY FRONT TO 15N52W. SCATTERED SHOWERS ANTICIPATED IN THE BROKEN TO OVERCAST LOW TO MID CLOUD FIELD SEEN WITHIN 30 NM OF THE FRONT. COLD AIR ADVECTION PATTERN EVIDENT BEHIND THE FRONT...WITH SCATTERED CELLULAR STRATOCUMULUS NOTED OVER MUCH OF THE W AND CENTRAL ATLC N OF 18N. 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. THE FRONT IN THE E/CENTRAL ATLC WILL SLOWLY WEAKEN WHILE THE SRN PERIPHERY OF HIGH PRES CONTINUES TO DOMINATE THE FAR E ATLC. LOW PRES CURRENTLY DEVELOPING OFF NEW JERSEY WILL AFFECT THE AREA N OF 25N MAINLY BETWEEN 40W-60W LATE TUE THROUGH EARLY THU. ANOTHER 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. $$ WILLIS