000 AXNT20 KNHC 140000 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED MAR 13 2013 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. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 09N13W TO 04N19W TO 01N23W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 01N23W TO EQ30W EQ40W TO THE NORTHERN COAST OF BRAZIL NEAR 2S44W. WIDESPREAD MODERATE TO ISOLATED STRONG CONVECTION IS FROM 3N-8N BETWEEN 13W AND 19W WHILE SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 3N BETWEEN 20W AND 26W. ...DISCUSSION... GULF OF MEXICO... IN THE MIDDLE TO UPPER LEVELS...W-SOUTHWESTERLY FLOW SURROUNDING A RIDGE CENTERED OVER THE CARIBBEAN IS ADVECTING MOISTURE FROM THE E PACIFIC TO THE GULF. THIS MOISTURE IS SUPPORTING MULTI-LAYERED CLOUDINESS S OF 26N. AN ENHANCEMENT OF GOES-E IR SATELLITE IMAGERY INDICATE SCATTERED SHOWERS FROM 20N-24N WEST OF 83W WHILE METAR OBSERVATIONS INDICATE BROKEN TO OVERCAST SKIES AND HAZE ALONG THE EAST COAST OF MEXICO INCLUDING THE YUCATAN PENINSULA. AT THE SURFACE NORTHEASTERLY FLOW DOMINATES THE BASIN. IN TERMS OF WIND MAGNITUDE... WINDS OF 15 KT DOMINATE WEST OF 91W WHILE STRONGER WINDS OF 20 KT SPREAD OVER THE EASTERN GULF S OF 27N. OVER THE COURSE OF 24 HOURS...A SURFACE RIDGE WILL BUILD OVER LOWER MISSISSIPPI AND LOUISIANA. THIS HIGH PRESSURE OVER THE NORTHERN GULF WILL MAINTAIN THE NORTHEASTERLY FLOW OVER THE REGION. CARIBBEAN SEA... AS OF 2100 UTC...A STATIONARY FRONT ENTERS THE WEST CARIBBEAN REGION BY CENTRAL CUBA NEAR 22N80W AND EXTENDS ALONG 20N84W 18N86W TO THE NORTHERN COAST OF HONDURAS NEAR 15N87W. BROKEN TO OVERCAST SKIES ARE ALONG THE STATIONARY FRONT WITH RAINSHOWERS CONCENTRATING S OF 21N. THE GFS MODEL SIX HOUR TOTAL PRECIPITATION SUGGEST THE STRONGEST RAINSHOWERS ARE IN THE COASTAL WATERS OF HONDURAS WHICH IS SUPPORTED BY METAR DATA IN THE NORTHERN COAST OF HONDURAS. A MIDDLE TO UPPER LEVEL RIDGE IS OVER THE CENTRAL CARIBBEAN PROVIDING W-SOUTHWESTERLY FLOW WEST OF 74W AND NORTHWESTERLY FLOW EAST OF THAT MERIDIAN. WATER VAPOR IMAGERY INDICATES VERY DRY AND STABLE AIR ALOFT E OF 82W WHICH IS FAVORING FAIR WEATHER CONDITIONS FOR THE REMAINDER BASIN EXCEPT FOR THE COASTAL WATERS OF PANAMA AND COLOMBIA. SCATTERED SHOWERS ARE OCURRING ALONG THE COAST OF PANAMA AND COLOMBIA ENHANCED BY SIGNIFICANT MOISTURE ADVECTION FROM THE EAST PACIFIC OCEAN. IN TERMS OF WIND...THE SOUTHERN...CENTRAL AND EASTERN CARIBBEAN IS UNDER THE INFLUENCE OF E-NE TRADEWINDS IN THE RANGE OF 10 TO 20 KT WITH STRONGER WINDS OF 25 KT OCCURRING ALONG THE COAST OF COLOMBIA. OVER THE WEST CARIBBEAN...NORTHERLY FLOW OF 20-25 KT IS WEST OF THE STATIONARY FRONT WHILE 5-15 KT WINDS ABOUNDS EAST OF THE FRONT. WITHIN THE COURSE OF 24 HOURS...THE FRONT IS EXPECTED TO DRIFT SOUTHEASTWARD BUT REMAIN APPROXIMATELY 80 NM WEST OF JAMAICA. IN TERMS OF WINDS...NORTHERLY FLOW WILL SPREAD WEST OF 78W WHILE E-NE TRADEWINDS WILL PERSIST IN THE REMAINDER OF THE BASIN. ATLANTIC OCEAN... IN THE MIDDLE TO UPPER LEVELS...THE EASTERNMOST SIDE OF A BROAD TROUGH OVER THE EASTERN CONUS N OF 31N IS SUPPORTING A COLD FRONT THAT ENTERS THE WEST ATLC BY 30N72W AND EXTENDS ALONG 26N75W TO NORTHERN WESTERN CUBA NEAR 22N79W WHERE IT BEACOMES STATIONARY. SCATTERED SHOWERS ARE WITHIN 180 NM EAST OF THE COLD FRONT N OF 25N AND WITHIN 90 NM WEST OF THE FRONT S OF 25N. FARTHER EAST IN THE W ATLC...A SURFACE 1019 MB HIGH IS LOCATED NEAR 27N64W WHICH IS EXPECTED TO DRIFT SOUTHEASTWARD WITHIN 24 HOURS. IN THE CENTRAL ATLC A 1003 MB LOW IS LOCATED NEAR 27N44W. AHEAD OF THE LOW A SURFACE TROUGH EXTENDS ALONG 26N37W 20N40W TO 15N45W WHERE IT TRANSITIONS TO A SHEARLINE THAT CONTINUES TO 12N53W TO 10N62W. WIDELY SCATTERED MODERATE CONVECTION ASSOCIATED TO BOTH THE LOW AND THE TROUGH IS CONFINED TO N OF 20N BETWEEN 33W-43W. BOTH FEAUTURES ARE BEING SUPPORTED BY A BROAD UPPER LEVEL TROUGH THAT EXTENDS FROM 10N TO 40N IN THE CENTRAL ATLC. A SURFACE RIDGE DOMINATES ACROSS THE EASTERN ATLC N OF 19N EAST OF 33W ANCHORED BY A 1016 MB HIGH CENTERED NEAR 28N20W. THIS HIGH IS EXPECTED TO DISSIPATE OVER THE NEXT 24 HOURS WHILE THE LOW OVER THE CENTRAL ATLC DRIFT EASTWARD. THE COLD FRONT OVER THE W ATLC WILL CONTINUE TO MOVE EASTWARD WHILE SLIGHTLY WEAKENS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ RAMOS