000 AXNT20 KNHC 261743 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST TUE FEB 26 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 10N15W TO 04N19W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 04N19W TO THE EQUATOR NEAR 33W THEN ALONG THE EQUATOR TO 41W. WIDELY SCATTERED MODERATE CONVECTION IS WITHIN 90 NM EITHER SIDE OF A LINE FROM 05N10W TO 02N36W TO 05N51W. ...DISCUSSION... GULF OF MEXICO... A VIGOROUS MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE MID- MISSISSIPPI RIVER VALLEY NEAR 37N91W THAT SUPPORTS A COLD FRONT ANALYZED INTO THE GULF WATERS VIA THE FLORIDA PANHANDLE NEAR 30N85W. THE FRONT EXTENDS S-SW ALONG 25N87W TO SOUTHERN MEXICO NEAR 18N93W. A PRE-FRONTAL SQUALL LINE LIES OVER THE NE GULF FROM THE FLORIDA BIG BEND NEAR 29N83W TO 27N85W AND IS PROVIDING MOST OF THE FOCUS AS THIS TIME FOR SCATTERED SHOWERS AND TSTMS OCCURRING WITHIN 60 NM EITHER SIDE OF THE BOUNDARY. THE CONVECTION STRETCHES NORTHEASTWARD OVER THE NORTHERN FLORIDA PENINSULA AND INTO PORTIONS OF THE SW NORTH ATLC. OTHERWISE... THE REMAINDER OF THE GULF WEST OF THE FRONT IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1016 MB HIGH CENTERED OVER NORTHERN MEXICO NEAR 27N101W. THE HIGH IS EXPECTED TO CONTINUE BUILDING EASTWARD INTO THE WESTERN GULF WITH LARGELY W-NW WINDS N OF 26N E OF 95W AND N-NW WINDS ELSEWHERE WEST OF THE COLD FRONT. CARIBBEAN SEA... MOSTLY WEST-NORTHWESTERLY UPPER LEVEL WINDS AND MID-LEVEL RIDGING IS PROVIDING FOR OVERALL STABLE AND TRANQUIL CONDITIONS ACROSS THE CARIBBEAN THIS AFTERNOON. WATER VAPOR IMAGERY CONFIRMS THIS WITH VERY DRY AIR AND SUBSIDENCE ALOFT EVIDENT FROM 08N-22N. AT THE SURFACE...LITTLE MOISTURE IS NOTED... HOWEVER AREAS OF SCATTERED CLOUDINESS CONTINUE TO MOVE WESTWARD WITHIN TRADES IN THE RANGE OF 15 TO 25 KT. THE HIGHEST OF THESE WINDS ARE S OF 15N BETWEEN 68W-78W...AND WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. LITTLE CHANGE IS EXPECTED SYNOPTICALLY OVER THE CARIBBEAN THROUGH WEDNESDAY WHEN A WEAKENED FRONTAL BOUNDARY APPROACHES WESTERN CUBA...THE YUCATAN CHANNEL...AND YUCATAN PENINSULA AND STALLS OVER ACROSS THE FAR NW CARIBBEAN UNTIL FRIDAY. ATLANTIC OCEAN... A VIGOROUS MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER A PORTION OF THE EASTERN U.S. CONUS AND IS PROVIDING FOR A LARGE AREA OF UPPER LEVEL DIFFLUENCE ACROSS THE SW NORTH ATLC WHERE SCATTERED SHOWERS AND TSTMS ARE OCCURRING AHEAD OF AN APPROACHING COLD FRONT ANALYZED OVER THE EASTERN GULF OF MEXICO. THE CONVECTION REMAINS N OF 28N W OF 70W...WITH SOME OF THIS ACTIVITY STRETCHING OVER THE CENTRAL AND NORTHERN FLORIDA PENINSULA. SOUTHERLY WINDS DOMINATE TO THE SOUTH OF THIS CONVECTIVELY ACTIVE AREA ON THE WESTERN PERIPHERY OF A WEAK SURFACE RIDGE EXTENDING FROM 32N67W TO 27N65W. TO THE EAST OVER THE CENTRAL ATLC...AN UPPER LEVEL TROUGH IS NOTED ON WATER VAPOR IMAGERY NORTH OF THE DISCUSSION AREA FOCUSED NEAR 39N44W THAT SUPPORTS A COLD FRONT FROM 32N43W SW TO 25N55W THEN WESTWARD TO 26N63W. ISOLATED SHOWERS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF THE FRONT AS IT CONTINUES TO MOVE E-SE. THE REMAINDER OF THE CENTRAL ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1021 MB HIGH CENTERED NEAR 28N35W. THE RIDGE AXIS EXTENDS SW TO 20N55W. FINALLY...A MIDDLE TO UPPER LEVEL LOW IS CENTERED NEAR 32N16W AND SUPPORTS A WEAKENING 1010 MB LOW CENTERED NW OF THE CANARY ISLANDS NEAR 30N21W. A SURFACE TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 31N10W TO THE LOW CENTER AND THEN AS A STATIONARY FRONT NW TO BEYOND 32N24W. INCREASED CLOUDINESS SURROUNDS THE LOW WITH ISOLATED SHOWERS POSSIBLE FROM 28N-33N BETWEEN 16W-26W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN