000 AXNT20 KNHC 281749 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST THU FEB 28 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 06N10W TO 02N14W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 02N14W TO 01N20W TO 01N32W TO THE EQUATOR NEAR 37W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 03N-07N BETWEEN 10W-15W. WIDELY SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 04N BETWEEN 21W-36W. ...DISCUSSION... GULF OF MEXICO... A BROAD MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE NORTHEASTERN CONUS WITH AN ASSOCIATED TROUGH AXIS THAT EXTENDS WESTWARD OVER THE MIDDLE MISSISSIPPI RIVER VALLEY AND SOUTHERN PLAINS TO A SHORTWAVE TROUGH PROGRESSING INTO WESTERN TEXAS. THIS TROUGHING SUPPORTS A COLD FRONT ANALYZED FROM THE SW NORTH ATLC ACROSS NORTHERN FLORIDA AND INTO THE NE GULF ALONG 30N84W TO 26N90W TO 24N96W TO THE MEXICO COAST NEAR 21N97W. THE FRONT REMAINS OVERALL PRECIPITATION-FREE BUT DOES HOWEVER REINFORCE NORTHERLY WINDS ACROSS THE GULF IN THE RANGE OF 10 TO 20 KT. TO THE SE OF THE APPROACHING COLD FRONT IS A STATIONARY FRONT ANALYZED FROM THE FLORIDA STRAITS TO THE YUCATAN CHANNEL AND PENINSULA. THIS FRONT HAS LINGERED OVER THE SE GULF FOR THE PAST 24-36 HOURS WITH LOW-LEVEL CLOUDINESS AND POSSIBLE ISOLATED SHOWERS NOTED ON SATELLITE IMAGERY WITHIN 180 NM NW OF THE FRONT. WITH THE APPROACHING COLD FRONT FROM THE NORTHWEST... THESE FRONT WILL MERGE AND BY LATE THURSDAY AND DRIFT SLOWLY SOUTHEAST INTO THE NW CARIBBEAN SEA. STRONG SURFACE RIDGING WILL EVENTUALLY SETTLE IN OVER THE WEEKEND WITH INCREASED N-NW WINDS ANTICIPATED OVER THE ENTIRE BASIN. 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 STABILITY WITH VERY DRY AIR AND SUBSIDENCE ALOFT EVIDENT FROM 10N-22N. AT THE SURFACE...LITTLE MOISTURE IS NOTED...HOWEVER AREAS OF WIDELY SCATTERED HIGH-LEVEL CLOUDINESS FANS OUT OVER THE BASIN S OF 19N. TRADE WINDS PERSIST IN THE RANGE OF 10 TO 20 KT. THE HIGHER RANGE OF THESE WINDS ARE GENERALLY S OF 15N BETWEEN 66W-78W...AND WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. A STATIONARY FRONT IS ANALYZED IN THE VICINITY OF THE YUCATAN CHANNEL AND SOUTHWARD ALONG INLAND PORTIONS OF THE YUCATAN PENINSULA. ISOLATED SHOWERS ARE MOSTLY CONFINED TO NW OF A LINE FROM 23N81W TO 19N88W. LITTLE CHANGE IS EXPECTED SYNOPTICALLY OVER THE CARIBBEAN THROUGH EARLY FRIDAY WHEN THE STATIONARY FRONT BEGINS TO DRIFT SOUTHEASTWARD AND GRADUALLY PICK UP SUSTAINED MOVEMENT AS A COLD FRONT EASTWARD BY THE WEEKEND. BY FRIDAY...UPPER LEVEL DYNAMICS WILL HAVE ARRIVED OVER THE NW CARIBBEAN SUPPORTING THE COLD FRONT WITH NORTHERLY WINDS INCREASING TO NEAR GALE AND POSSIBLY GALE FORCE CONDITIONS OFF THE COAST OF NICARAGUA BY EARLY SUNDAY. ATLANTIC OCEAN... A BROAD MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE NORTHEASTERN CONUS AND IS PROVIDING SUPPORT FOR A PAIR OF FRONTAL BOUNDARIES ENTERING THE DISCUSSION AREA THIS AFTERNOON. THE WESTERN-MOST FRONT IS A COLD FRONT ANALYZED FROM 32N76W TO THE FLORIDA PENINSULA NEAR JACKSONVILLE AND REMAINS NEARLY PRECIPITATION-FREE. STRONGER WESTERLY SURFACE WINDS ARE EXPECTED N OF 30 IN WAKE OF THIS FRONT. FARTHER SE...A STATIONARY FRONT EXTENDS FROM 32N67W TO THE BAHAMAS NEAR 25N77W AND INTO THE SE GULF OF MEXICO. CLOUDINESS IS NOTED ACROSS THE SW NORTH ATLC WITHIN 180 NM EITHER SIDE OF THE BOUNDARY WITH EMBEDDED ISOLATED SHOWERS AND TSTMS OCCURRING PRIMARILY WITHIN 90 EITHER SIDE OF THE FRONT. FARTHER EAST...ANOTHER BROAD UPPER LEVEL LOW IS CENTERED OVER THE CENTRAL PORTION OF THE NORTH ATLC NEAR 41N36W THAT SUPPORTS A COLD FRONT ANALYZED FROM 32N26W TO 28N30W TO 21N46W. WIDELY SCATTERED SHOWERS ARE OCCURRING WITHIN 240 NM EAST OF THE FRONT N OF 25N AND WITHIN 90 NM EITHER SIDE OF THE FRONT W OF 33W. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1020 MB HIGH CENTERED NEAR 22N26W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN