000 AXNT20 KNHC 090543 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT MON MAR 09 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...SPECIAL FEATURES... A STRONG PRESSURE GRADIENT BETWEEN LOWER PRESSURE ACROSS COLOMBIA AND A RIDGE EXTENDING ACROSS THE SW NORTH ATLC REGION IS GENERATING GALE FORCE CONDITIONS FOR THE COASTAL WATERS OF COLOMBIA FROM 10.5N-13.5N BETWEEN 73W-77W. THESE CONDITIONS ARE EXPECTED TO PERSIST THROUGH LATE TUESDAY. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 11N15W TO 06N14W TO 04N15W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 04N15W TO THE EQUATOR NEAR 28W. SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 03N BETWEEN 21W-28W. ...DISCUSSION... GULF OF MEXICO... WEST-SOUTHWESTERLY FLOW ALOFT PREVAILS OVER THE GULF THIS EVENING WITH AN APPROACHING MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH NOTED ON WATER VAPOR IMAGERY CENTERED OVER NW MEXICO NEAR 29N107W. WITH THE UPPER LEVEL DYNAMICS IN PLACE TO THE WEST...AS OF 09/0300 UTC A 1016 MB SURFACE LOW IS ANALYZED OFF THE COAST OF SOUTHERN TEXAS NEAR 27N97W WITH A FORMING STATIONARY FRONT EXTENDING EAST TO 28N92W AND SOUTH TO NEAR 25N98W ACROSS INLAND NE MEXICO. THIS DEVELOPING AREA OF LOW PRESSURE IS ACCOMPANIED BY SCATTERED SHOWERS GENERALLY IN THE VICINITY OF AND NORTH OF THE FRONT ACROSS THE NW GULF WATERS AND INLAND PORTIONS OF THE LOWER MISSISSIPPI RIVER VALLEY AND SE TEXAS. STRONGER CONVECTION IS ALSO NOTED ACROSS INLAND PORTIONS OF NE MEXICO N OF 24N BETWEEN 98W-102W. TO THE SOUTH OF THIS LOW...SURFACE TROUGHING EXTENDS OFFSHORE ALONG THE EASTERN MEXICO COAST FROM 24N97W TO 19N94W. TO THE EAST ACROSS THE REMAINDER OF THE BASIN...MODERATE TO FRESH E-SE WINDS ARE OCCURRING ON THE SOUTHERN PERIPHERY OF WEAKENING SURFACE RIDGING ANCHORED TO THE NORTH ACROSS THE SE CONUS. LOOKING AHEAD...THE LOW PRESSURE AREA WILL LIFT TO THE N- NE THROUGH EARLY TUESDAY WITH THE ASSOCIATED COLD FRONT EXTENDING SOUTHWARD INTO THE WESTERN GULF WATERS AND GRADUALLY MOVE EAST THROUGH EARLY WEDNESDAY. BY WEDNESDAY THE FRONT WILL STALL AS ANOTHER AREA OF LOW PRESSURE DEVELOPS ACROSS THE SW GULF AND QUICKLY LIFTS NORTHWARD TOWARD THE SE LOUISIANA COAST. BOTH THE GFS AND ECMWF GENERALLY AGREE WITH THIS OVERALL SCENARIO THROUGH THURSDAY MORNING. CARIBBEAN SEA... WEST TO NORTHWESTERLY FLOW IS NOTED ON WATER VAPOR IMAGERY OVER MUCH OF THE CARIBBEAN BASIN THIS EVENING WITHIN VERY STRONG SUBSIDENCE AND DRY AIR ALOFT THAT CONTINUES TO PROVIDE OVERALL STABILITY AND FAIR CONDITIONS. ASIDE FROM PASSING LOW-TOPPED ISOLATED SHOWERS ACROSS THE EASTERN CARIBBEAN...AND ALONG THE CENTRAL AMERICA COAST...THE LARGEST IMPACT REMAINS A LARGE AREA OF FRESH TO STRONG TRADES W OF 83W. THIS AREA ALSO INCLUDES NEAR GALE TO GALE FORCE NE TO E WINDS WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. WITH STRONG HIGH PRESSURE ANCHORED ACROSS THE SW NORTH ATLC REGION...THIS OVERALL SYNOPTIC PATTERN IS EXPECTED TO PERSIST DURING THE NEXT FEW DAYS. ...HISPANIOLA... OVERALL DRY AND STABLE AIR ALOFT IS MAINTAINING FAIR CONDITIONS AND MOSTLY CLEAR SKIES FOR THE ISLAND THIS EVENING. THIS OVERALL SYNOPTIC PATTERN IS EXPECTED TO PERSIST FOR THE NEXT FEW DAYS WITH A SMALL PROBABILITY OF A PASSING ISOLATED SHOWER WITHIN TRADE WIND FLOW. ATLANTIC OCEAN... GENERALLY WESTERLY FLOW ALOFT INFLUENCES MUCH OF THE SW NORTH ATLC REGION CURRENTLY ON THE NORTHERN PERIPHERY OF A E-W STRETCHED UPPER LEVEL RIDGE AXIS EXTENDING FROM OVER EASTERN CUBA TO NEAR 27N46W. WITH A VERY PROGRESSIVE PATTERN IN PLACE...THE ONLY BOUNDARY EXTENDING INTO THE DISCUSSION AREA IS A WEAK STATIONARY FRONT ANALYZED FROM 32N51W TO 27N64W TO THE NW BAHAMAS NEAR 25N78W. SHALLOW ISOLATED SHOWERS ARE OCCURRING WITHIN 120 NM NORTH OF THE FRONT. OTHERWISE...A 1026 MB HIGH IS CENTERED NEAR 31N72W MAINTAINING MOSTLY FAIR WEATHER TO THE NORTH OF THE FRONT. TO THE SOUTH OF THE UPPER LEVEL RIDGE AXIS...A CUT-OFF MIDDLE TO UPPER LEVEL LOW IS CENTERED NEAR 17N48W THAT SUPPORTS A SURFACE TROUGH TO THE EAST OF THE LESSER ANTILLES FROM 14N60W TO 19N59W. LOW-TOPPED ISOLATED SHOWERS ARE OCCURRING MOSTLY WEST OF THE TROUGH AXIS FROM 14N-21N BETWEEN 59W-69W. FINALLY...ANOTHER MIDDLE TO UPPER LEVEL LOW IS CENTERED OFF THE COAST OF WEST AFRICA NEAR 23N20W THAT SUPPORTS A WEAK 1011 MB LOW CENTERED NEAR 23N22W. WHILE OVERALL CONVECTION LACKS WITH THIS FEATURE...THE CIMSS SAHARAN AIR LAYER TRACKING PRODUCT INDICATES A STRONG PRESENCE OF SAHARAN DUST FROM 18N-32N E OF 35W. THE LAST SEVERAL HOURS OF SURFACE OBSERVATIONS FROM NOUADHIBOU INTL AIRPORT IN WESTERN MAURITANIA INDICATE REDUCED VISIBILITY AND BLOWING DUST. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN