000 AXNT20 KNHC 122357 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST THU FEB 12 2015 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... A GALE WARNING IS IN EFFECT FOR A PORTION OF THE W ATLC N OF 29N E OF THE FRONT THAT EXTENDS FROM 32N48W TO 25N51W. THE WINDS WILL BE BELOW GALE FORCE LATER THIS EVENING. PLEASE SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL ATLC NEAR 8N13W THEN ALONG 6N15W TO 4N19W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 2N23W 4N35W TO 5N46W. ISOLATED MODERATE CONVECTION IS FROM 2N TO JUST S OF THE EQUATOR BETWEEN 17W-34W. ...DISCUSSION... GULF OF MEXICO... AN UPPER TROUGH COVERS THE E CONUS TO THE N GULF COAST WITH NEAR ZONAL SW FLOW ALOFT ACROSS THE GULF WATERS. THIS UPPER TROUGH IS SUPPORTING A COLD FRONT THAT EXTENDS ACROSS THE N GULF FROM A 1008 MB LOW OVER SOUTH CAROLINA INTO THE GULF OVER THE BIG BEND AREA OF FLORIDA ALONG 27N90W TO OVER NE MEXICO JUST S OF BROWNSVILLE TEXAS. A SURFACE RIDGE IS BRIDGING THE FRONT ANCHORED BY A 1038 MB HIGH OVER THE UPPER MISSISSIPPI VALLEY. THE UPPER RIDGE IS ADVECTING UPPER LEVEL MOISTURE ACROSS THE GULF WHILE THE LOWER LEVELS ARE VERY DRY THIS EVENING. THE SE SURFACE FLOW IS BANKING LOW CLOUDS ALONG THE EASTERN SLOPE OF THE SIERRA MADRE MOUNTAINS WHICH ARE SPILLING OVER INTO THE GULF WATERS WITHIN 60 NM ALONG THE COAST OF MEXICO FROM VERACRUZ TO TUXPAN LEAVING THE REMAINDER OF THE GULF WITH CLEAR SKIES. THE COLD FRONT WILL MOVE INTO THE THE W ATLC TONIGHT AND INTO THE NW CARIBBEAN LATE FRI/EARLY SAT. SURFACE RIDGE WILL BECOME FIRMLY ESTABLISHED IN THE WAKE OF THE FRONT FOR THE WEEKEND. CARIBBEAN SEA... BROAD UPPER RIDGE EXTENDS FROM OVER SOUTH AMERICA ACROSS THE LESSER ANTILLES INTO THE W/CENTRAL ATLC GIVING THE CARIBBEAN SW TO W FLOW ALOFT. A DEEP LAYERED TROUGH OVER THE CENTRAL ATLC EXTENDS A COLD FRONT TO THE LEEWARD ISLANDS NEAR MONTSERRAT WHERE IT DISSIPATES TO 26N67W. ISOLATED SHOWERS ARE POSSIBLE N OF THE FRONT TO OVER THE VIRGIN ISLANDS AND PUERTO RICO. NE SURFACE FLOW IS BANKING SCATTERED SHOWERS INLAND AND WITHIN 90 NM ALONG THE COAST FROM S NICARAGUA S OF 13N TO PANAMA W OF 81W. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN WITH FAIR WEATHER THIS EVENING. THE DISSIPATING FRONT WILL MOVE SLOWLY SE THROUGH EARLY TONIGHT THEN STALL ALONG 16N LATE TONIGHT AND GRADUALLY DISSIPATE THROUGH SAT. THE GULF OF MEXICO FRONT WILL MOVE INTO THE FAR NW CARIBBEAN LAT4E FRI/EARLY SAT WHERE IT WILL STALL AND DISSIPATE BY LATE SAT. ...HISPANIOLA... LINGERING MOISTURE FROM THE RECENT FRONTAL PASSAGE IS ALLOWING ISOLATED SHOWERS TO DEVELOP THIS AFTERNOON ACROSS THE DOMINICAN REPUBLIC. THIS MOISTURE WILL REMAIN AND COUPLED WITH THE NE SURFACE FLOW COULD GENERATE ISOLATED SHOWERS THROUGH SAT. ATLANTIC OCEAN... AN UPPER RIDGE THAT EXTENDS FROM SOUTH AMERICA ACROSS THE LESSER ANTILLES COVERS THE W INTO THE CENTRAL ATLC. THE DEEP LAYERED TROUGH OVER THE CENTRAL ATLC EXTENDS A COLD FRONT INTO THE AREA NEAR 32N48W ALONG 22N42W INTO THE CARIBBEAN NEAR MONTSERRAT WHERE IT DISSIPATES IN THE CARIBBEAN. A SURFACE TROUGH FOLLOWS THE FRONT ENTERING THE AREA NEAR 32N52W TO 24N60W. SCATTERED SHOWERS ARE WITHIN 45 NM E OF THE FRONT. THE GALE WARNINGS IN THE SPECIAL FEATURE IS ASSOCIATED WITH FRONT. STRONG SUBSTANCE AND DRY AIR ALOFT ARE W OF THIS FRONT COVERING THE W ATLC. AN UPPER TROUGH COVERS THE E ATLC EXTENDING FROM THE CANARY ISLANDS TO 21N34W WHILE AT THE SURFACE IS A SURFACE TROUGH THAT EXTENDS FROM 27N38W TO 22N35W. AN UPPER RIDGE EXTENDS FROM OVER AFRICA INTO THE W TROPICAL ATLC IS PROVIDING DIFFLUNCE ALOFT TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 120/150 NM OF LINE FROM 15N29W TO THE COAST OF AFRICA NEAR DAKAR AND INCLUDES THE NORTHERN CAPE VERDE ISLANDS. A SURFACE RIDGE DOMINATES THE E ATLC N OF 10N E OF 45W ANCHORED BY A PAIR OF 1026 MB HIGHS NEAR 33N24W AND 36N29W. THE CENTRAL ATLC COLD FRONT WILL SHIFT E AND STALL ALONG 30N45W 20N56W TO 16N62W LATE TONIGHT AND GRADUALLY DISSIPATE THROUGH SAT. A COLD FRONT WILL MOVE OFF THE GEORGIA COAST THIS EVENING AND EXTEND FROM NEAR 32N64W TO THE CENTRAL BAHAMAS TO W CUBA BY FRI NIGHT THEN BECOME STATIONARY FROM NEAR 32N58W ALONG 26N65W TO SE BAHAMAS EARLY SAT AND DISSIPATE SUN. ANOTHER COLD FRONT WILL MOVE RAPIDLY ACROSS THE W ATLC SAT NIGHT THROUGH SUN NIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW