000 AXNT20 KNHC 170536 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SAT MAR 17 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 0345 UTC. ...ITCZ... ITCZ AXIS IS ALONG 6N11W 3N30W TO NEAR EQ48W. THE ITCZ HAS BECOME QUITE ACTIVE WITH CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ALONG THE AXIS AND WITHIN 50 NM N OF THE AXIS. ...DISCUSSION... GULF OF MEXICO... A SHARP UPPER LEVEL TROUGH AXIS IS ALONG 85W AND CONTINUES TO DIG SEWD. A COLD FRONT EXTENDS FROM CENTRAL FLORIDA WSW TO 24N90W AND 25N95W. THE FRONT IS MOVING SE 20 KT. MOST OF THE CONVECTIVE ACTIVITY IS ASSOCIATED WITH A PRE-FRONTAL TROUGH THAT HAS MOVED INTO THE WRN BAHAMAS AND WRN CUBA. THE FRONT IS FORECAST TO MOVE E OF SOUTH FLORIDA AFTER MIDNIGHT. WINDS AND SEAS ARE EXPECTED TO INCREASE W OF THE FRONT AS HIGH PRES BUILDS OVER THE GULF AND SW ATLC. CARIBBEAN... A SHORT-WAVE TROUGH IN THE MID LEVELS WAS ALONG 75W MOVING E 35 KT. THE TROUGH IS SUPPORTING SCATTERED SHOWERS AND TSTMS OVER SE CUBA AND THE SE BAHAMAS THIS MORNING. A BROAD RIDGE DOMINATES THE ERN PORTION OF THE CARIBBEAN. STRONG SWLY WINDS ARE ADVECTING UPPER LEVEL MOISTURE AND HIGH CLOUDS FROM CONVECTION OVER N SOUTH AMERICA. TRADE WINDS HAVE DECREASED OVER THE WRN CARIB AS LOW PRES LOCATED N OF THE AREA WEAKENS THE PRESSURE GRADIENT. MODERATE TO FRESH ELY WINDS CONTINUE OVER THE CENTRAL AND ERN PORTIONS. A COLD FRONT IS EXPECTED TO PUSH INTO THE NW CARIBBEAN LATER TODAY INCREASING THE CHANCE OF SHOWERS AS IT MOVES EWD. DRIER AND SLIGHTLY COOLER WEATHER WILL FOLLOW THE FRONT WITH GUSTY NW WINDS. WESTERN AND CENTRAL ATLANTIC... A BAND OF TSTMS EXTENDS FROM 31N75W SSW TO THE NRN BAHAMAS AND IS MOVING E 20 KT. THE TSTMS ARE AHEAD OF A COLD FRONT THAT EXTENDS FROM 31N78W TO CENTRAL FL. AN OLD FRONTAL BOUNDARY EXTENDS FROM NEAR 31N42W TO 24N50W AND IS DIFFUSE BACK TO 23N60W TO 28N70W. THE WRN PORTION IS MOVING N AS A BAND OF LOW AND MID CLOUDS IN RESPONSE TO THE APPROACHING COLD FRONT. ISOLATED CONVECTION CONTINUES ALONG THE FRONT N OF 29N NEAR 42W. EASTERN ATLANTIC... A STRONG HIGH WAS LOCATED WELL N OF THE REGION ALONG 30W AND EXTENDS SW OVER THE REGION. THE RIDGE IS PRODUCING A STRONG NE WIND WHICH IS MOSTLY DEVOID OF CLOUDINESS N OF THE CAPE ISLANDS. THE AIR PICKS UP MOISTURE AS IT MOVES SW AND BROKEN LOW AND MID LEVEL CLOUDINESS DEVELOPS W OF 27W. THE CLOUDS CONTINUE WWD BECOMING MOSTLY SCATTERED W OF 55W. THE ENTIRE AREA IS N OF 8N IS DEVOID OF ANY CONVECTION. A SUBTROPIC JET IS EVIDENT FROM NEAR 15N61W TO 18N52W THEN HEADS ESE TO 13N20W. ONLY A FEW CIRRUS CLOUDS ACCOMPANY THE JET INDICATING A MOSTLY DRY UPPER ATMOSPHERE OVER THE REGION. A UPPER LOW WAS LOCATED NEAR 32N20W MOVING S 20 KT AND WILL BE AFFECTING THE CAPE VERDE ISLANDS LATER TODAY WITH SCATTERED SHOWERS AND TSTMS. $$ RRG