000 AXNT20 KNHC 310541 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU MAR 31 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. ...ITCZ... ITCZ AXIS IS ANALYZED ALONG 6N10W 3N21W 1N29W CROSSING THE EQUATOR NEAR 35W THEN S OF THE EQUATOR INTO SOUTH AMERICA. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 1N-5N BETWEEN 21W-40W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER TROUGH IS OVER THE CENTRAL PLAIN STATES MOVING TOWARD THE MISSISSIPPI VALLEY WITH A SHORTWAVE UPPER TROUGH EXTENDING FROM THE NE GULF NEAR 28N86W ACROSS NE FLORIDA TO ALONG THE EASTERN SEABOARD GIVING THE GULF WATERS SW FLOW ALOFT. THESE TWO FEATURES AT 31/0300 UTC ARE SUPPORTING A COMPLEX FRONTAL SYSTEM WITH A COLD FRONT EXTENDING FROM A 1003 MB OFF THE NORTH CAROLINA COAST THROUGH 32N77W TO OVER JACKSONVILLE FLORIDA TO A 1006 MB LOW NEAR PANAMA CITY CONTINUING INTO THE GULF ALONG 29N85W TO 27N87W WHERE IT BECOMES STATIONARY ALONG 25N94W 22N96W TO THE COAST OF S MEXICO NEAR THE ISTHMUS OF TEHUANTEPEC. A SEPARATE STATIONARY REMAINS ALONG THE E SLOPE OF THE SIERRA MADRE MOUNTAINS. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 26N-28N E OF 86W TO INLAND OVER THE FLORIDA PENINSULA. OVERCAST MULTILAYERED CLOUDS WITH POSSIBLE ISOLATED SHOWERS ARE W OF THE GULF COLD/STATIONARY FRONT. THE FRONT WILL REACH FROM THE BIG BEND AREA OF FLORIDA LATER THIS MORNING BEFORE BECOMING DIFFUSE OVER THE SE GULF BY FRI MORNING. ANOTHER COLD FRONT WILL CLIP THE FAR NE GULF FRI MOVING E OF THE AREA FRI NIGHT. HIGH PRES DEVELOPS OVER THE CENTRAL GULF FRI THEN SHIFTS E INTO THE ATLC WITH SOUTHERLY RETURN FLOW ACROSS THE GULF SAT THROUGH MON. CARIBBEAN SEA... A BROAD UPPER RIDGE ANCHORED OVER THE TROPICS COVERS THE CARIBBEAN WITH STRONG SUBSIDENCE AND DRY STABLE AIR COVERING ALL BUT THE FAR S CARIBBEAN. A SURFACE TROUGH OVER THE YUCATAN PENINSULA IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS MAINLY INLAND AND WITHIN 60 NM ALONG THE COAST BETWEEN 19N-21N. MOST OF THE CARIBBEAN IS UNDER CLEAR SKIES TONIGHT WITH THE EXCEPTION OF THE SW CARIBBEAN S OF 12N BETWEEN 76-79W WHERE ISOLATED SHOWERS ARE POSSIBLE. FRESH TO STRONG TRADE WINDS DIMINISH IN GULF OF HONDURAS LATER TODAY AS SURFACE RIDGE OVER THE W ATLC WEAKENS AND SHIFTS E. FRESH TRADE WINDS PERSIST OVER E CARIBBEAN THROUGH SAT. TRADE WINDS INCREASE ACROSS CARIBBEAN SUN AND MON AS THE RIDGE REBUILDS OVER THE W ATLC. ATLANTIC OCEAN... AN UPPER TROUGH THAT IS INLAND OVER THE E CONUS IS SUPPORTING AT 31/0300 UTC A COLD FRONT THAT EXTENDS FROM 1003 MB LOW ALONG THE COAST OF NORTH CAROLINA THROUGH 32N77W INTO THE GULF OF MEXICO ACROSS NE FLORIDA NEAR JACKSONVILLE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 60 NM OF LINE FROM 27N77W TO 29N73W WITH ISOLATED SHOWERS COVERING THE REMAINDER OF THE AREA W OF 71W TO INLAND OVER THE CONUS E COAST. AN UPPER TROUGH COVERS THE CENTRAL ATLC N OF 27N BETWEEN 37W-53W WHILE A BROAD UPPER RIDGE COVERS THE REMAINDER OF THE CENTRAL ATLC INTO THE E ATLC W OF 30W. A WEAK COLD FRONT EXTENDS INTO THE CENTRAL ATLC NEAR 32N44W SW TO 28N58W WHERE IT BECOMES STATIONARY TO 27N68W. A SURFACE TROUGH IS TO THE E EXTENDING FROM 31N41W ALONG 28N45W TO 27N50W. ANY SHOWER ACTIVITY IS N OF THE DISCUSSION AREA. A WEAK SURFACE TROUGH IS OVER THE SW ATLC EXTENDING FROM NEAR 23N64W ALONG 21N66W TO THE MONA PASSAGE GENERATING ISOLATED SHOWERS FROM 19N-24N BETWEEN 62W-71W. THE FAR E ATLC IS DOMINATED BY A NEAR STATIONARY UPPER LOW NEAR 28N22W AND A SURFACE RIDGE ANCHORED BY A 1029 MB HIGH OVER PORTUGAL WITH A RIDGE AXIS EXTENDING THROUGH 32N25W ALONG 26N38W TO 25N56W. MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR REMAINS OVER THE ATLC S OF 24N LIMITING SHOWER ACTIVITY LEAVING THE REMAINDER OF THE ATLC WITH FAIR WEATHER AGAIN TONIGHT. STRONG AND GUSTY S TO SW SURFACE FLOW TO NEAR GALE FORCE IS OFF N FLORIDA COAST AHEAD OF COLD FRONT THROUGH TODAY. THE FRONT WILL REACH THE W ATLC TO FLORIDA KEYS FRI MORNING THEN STALL FROM JUST E OF BERMUDA TO SE BAHAMAS FRI NIGHT AS REINFORCING COLD FRONT DIVES DOWN FROM THE NW. BOTH FRONTS WILL SHIFT INTO THE CENTRAL ATLC BY SUN MORNING WITH A SURFACE RIDGE BUILDING IN ACROSS AREA THROUGH MON. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW