000 AXNT20 KNHC 170603 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU MAR 17 2011 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTION OF SOUTH AMERICA...AND 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 0515 UTC. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED FROM 6N10W 3N18W ACROSS THE EQUATOR NEAR 26W CONTINUING SW AND INLAND SOUTH AMERICA. SCATTERED/ NUMEROUS STRONG CONVECTION IS WITHIN 90 NM ALONG THE COAST OF LIBERIA BETWEEN 9W AND THE BORDER OF SIERRA LEONE AND WITHIN 45 NM OF LINE FROM 8N9W TO 4N19W. SCATTERED STRONG CONVECTION IS WITHIN 60 NM OF LINE FROM 2N21W TO 3N26W WITH CLUSTERS OF SIMILAR CONVECTION WITHIN 45 NM 2.5N BETWEEN 18W-21W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL TROUGH DIPS S OVER THE NE GULF INTO THE W ATLC TRAILING ACROSS THE GULF FROM FORT MYERS FLORIDA TO TAMPICO MEXICO. AN ASSOCIATED SURFACE FRONT AT 17/0300 UTC IS BEGINNING TO DISSIPATE AS IT CROSSES NE FLORIDA TO THE CENTRAL GULF NEAR 27N89W. A PRE-FRONTAL SURFACE TROUGH EXTENDS FROM 29N86W TO 25N90W WITH ISOLATED SHOWERS WITHIN 30 NM OF THE TROUGH AXIS. A WEAK 1025 MB HIGH IS N OF THE FRONT OFF THE ALABAMA COAST GIVING THE NW GULF SE RETURN FLOW WHICH BANKING LOW CLOUDS INLAND OVER TEXAS. A SECOND WEAK SURFACE TROUGH IS IN THE E BAY OF CAMPECHE EXTENDING FROM 22N90W TO OVER S MEXICO NEAR 17N93W WITH ISOLATED SHOWERS E OF THE TROUGH TO INLAND OVER THE YUCATAN PENINSULA. THIS IS LEAVING THE REMAINDER OF THE GULF UNDER CLEAR SKIES TONIGHT. THE FRONT IS EXPECTED TO BE GONE LATER THIS MORNING AS HIGH PRESSURE RE-BUILDS OF THE SE CONUS/N GULF THROUGH FRI PRODUCING MODERATE TO FRESH E TO SE BREEZE ACROSS ENTIRE GULF ON SAT. CARIBBEAN SEA... AN UPPER RIDGE COVERS THE CARIBBEAN ANCHORED OVER THE DEEP TROPICAL ATLC NEAR 12N54W GIVING THE CARIBBEAN S TO SW FLOW ALOFT. THE SURFACE RIDGE OVER THE W ATLC CONTINUES TO MAINTAIN ENE TRADE WINDS ACROSS THE BASIN WITH STRONGER WINDS ALONG THE COAST OF COLOMBIA. REMNANT LOW LEVEL MOISTURE CONTINUES TO PRODUCE ISOLATED SHOWERS MAINLY OVER THE SE CARIBBEAN S OF 16N BETWEEN THE WINDWARD ISLANDS AND 65W AND OVER THE NW CARIBBEAN WITHIN 90 NM OF LINE SW HAITI TO NE HONDURAS. THE SURFACE RIDGE OVER THE W ATLC WILL MAINTAIN THE TRADE WINDS THROUGH FRI. ATLANTIC OCEAN... THE UPPER TROUGH OVER THE NE GULF OF MEXICO IS MOVING INTO THE W ATLC W OF 72W SUPPORTING A WEAK COLD FRONT OVER THE W ATLC ENTERING THE REGION AT 17/0300 UTC NEAR 32N77W TO NEAR JACKSONVILLE FLORIDA WHERE IT BEGINS TO DISSIPATE AS IT ENTERS THE GULF OF MEXICO. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE N OF THE DISCUSSION AREA. A SECOND UPPER TROUGH IS OVER THE CENTRAL ATLC N OF 25N BETWEEN 35W-60W SUPPORTING A WEAK COLD FRONT THAT ENTERS THE REGION NEAR 32N38W TO 29N45W WHERE IT DISSIPATES TO 26N56W. A PRE-FRONTAL SURFACE TROUGH EXTENDS FROM 30N39W ALONG 27N45W TO 23N50W WITH SCATTERED SHOWERS WITHIN 90 NM E OF THE SURFACE TROUGH N OF 27N AND ISOLATED SHOWERS BETWEEN THE SURFACE TROUGH AND THE COLD FRONT. DRY UPPER AIR IS OVER THE TROPICS FROM 10N-24N E OF BAHAMAS TO OVER AFRICA. HOWEVER...A PERSISTENT AREA OF LOW LEVEL MOISTURE IS OVER THE CENTRAL AND W TROPICAL ATLC FROM 13N-24N BETWEEN 44W-56W ANALYZED WITH A SURFACE TROUGH THAT EXTENDS FROM 23N46W TO 18N49W AND A SECOND FROM 20N54W TO 16N53W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 90 NM EITHER SIDE OF BOTH TROUGH AXIS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW