000 AXNT20 KNHC 252345 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST MON FEB 25 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. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 04N19W TO 01N31W TO 01N50W. WIDELY SCATTERED MODERATE CONVECTION IS WITHIN 120 NM OF THE AXIS BETWEEN 25W AND 55W. ...DISCUSSION... GULF OF MEXICO... A VIGOROUS MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE SOUTHERN U.S. PLAINS NEAR 35N98W THAT SUPPORTS A PAIR OF FRONTS ANALYZED ACROSS THE GULF WATERS THIS EVENING. AS OF 25/2100 UTC ...A STATIONARY FRONT EXTENDS FROM THE LOUISIANA COAST NEAR THE MOUTH OF THE MISSISSIPPI RIVER TO THE FLORIDA PENINSULA NEAR 29N83W. THE OTHER FRONTAL BOUNDARY...A COLD FRONT...EXTENDS FROM THE COAST NEAR THE TEXAS-LOUISIANA BORDER SOUTH-SOUTHWESTWARD ACROSS THE WESTERN GULF TO THE MEXICAN COAST NEAR 21N97W. MOSAIC DOPPLER RADAR IMAGERY AND LIGHTNING DATA INDICATE WIDESPREAD SHOWERS AND SCATTERED TSTMS ARE OCCURRING N OF 28N E OF THE COLD FRONT...INCLUDING INLAND PORTIONS OF LOUISIANA... MISSISSIPPI...SOUTHERN ALABAMA...THE FLORIDA PANHANDLE...AND SOUTHERN GEORGIA. LAND-BASED OBSERVATIONS ACROSS SOUTHERN TEXAS AND A FEW SHIP AND OFFSHORE OIL PLATFORM OBSERVATIONS IN THE NW GULF SHOW STRONG N-NW WINDS CLOSE TO GALE FORCE WEST OF THE COLD FRONT WITH DEWPOINTS DROPPING RAPIDLY AFTER THE FRONTAL PASSAGE. DOPPLER RADAR AND SATELLITE IMAGERY INDICATES SCATTERED SHOWERS AND TSTMS ARE OCCURRING WITHIN 30 NM EITHER SIDE OF THE COLD FRONT NORTH OF 26N. THE REMAINDER OF THE GULF IS UNDER THE INFLUENCE OF SOUTH-SOUTHWESTERLY WINDS IN THE RANGE OF 10 TO 20 KT. AS THE COLD FRONT SWEEPS EASTWARD THROUGH EARLY TUESDAY...THE NORTHERLY WINDS WILL SPREAD SOUTHEASTWARD OVER MUCH OF THE WESTERN GULF WITH GALE FORCE CONDITIONS EXPECTED THROUGH THE OVERNIGHT HOURS N OF 26N WEST OF THE FRONT. THE COLD FRONT SHOULD SPREAD ACROSS THE ENTIRE GULF AND REACH SOUTH FLORIDA BY LATE TUESDAY. CARIBBEAN SEA... UPPER LEVEL CONFLUENT FLOW IS OVER MUCH OF THE CARIBBEAN THIS EVENING PROVIDING FOR OVERALL SUBSIDENT CONDITIONS WITH NO ORGANIZED DEEP CONVECTION AS EVIDENCED BY THE WATER VAPOR IMAGERY. LITTLE MOISTURE IS NOTED IN THE TOTAL PRECIPITABLE WATER IMAGERY...HOWEVER...SCATTERED CLOUDINESS CONTINUES TO MOVE WESTWARD WITHIN BRISK TRADES IN THE RANGE OF 15 TO 25 KT. THE HIGHEST OF THESE WINDS ARE IN THE EXTREME NORTHWESTERN CARIBBEAN SEA AND WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. AS A OLD FRONT APPROACHES WESTERN CUBA ON TUESDAY...WINDS IN THE NORTHWESTERN CARIBBEAN WILL SLACKEN SOME WHILE THE REMAINDER OF THE CARIBBEAN WILL SEE LITTLE CHANGE. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH AND LOW IS CENTERED OVER THE WESTERN NORTH ATLC NEAR 41N54W THAT SUPPORTS A COLD FRONT ENTERING THE DISCUSSION AREA NEAR 32N54W EXTENDING W-SW TO 27N69W AND BECOMES STATIONARY TO THE FLORIDA PENINSULA COAST NEAR 29N81W. WITH MOST OF THE UPPER LEVEL DYNAMICS NORTH OF THE AREA...ONLY SCATTERED SHOWERS ARE OCCURRING WITHIN 120 NM EITHER SIDE OF THE COLD FRONT...AND N OF 27N IN ASSOCIATION WITH THE STATIONARY FRONT. FARTHER EAST ACROSS THE CENTRAL ATLC...UPPER LEVEL WESTERLY FLOW DOMINATES AND GENERALLY SUPPORTS WEAK SURFACE RIDGING ANCHORED BY A 1019 MB HIGH CENTERED NEAR 28N39W. FINALLY...A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY NEAR 33N24W THAT SUPPORTS A 1007 MB LOW CENTERED NEAR 32N24W AND THE ASSOCIATED DISSIPATING COLD FRONT FROM THE LOW CENTER TO 28N21W TO 20N29W. SCATTERED SHOWERS ARE OCCURRING WITHIN 150 NM EAST OF THE FRONT N OF 26N...AND WITHIN 60 NM EITHER SIDE OF THE FRONT S OF 26N. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN/LANDSEA