000 AXNT20 KNHC 091048 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 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-14N 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 06N10W TO 04N14W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 04N14W TO THE EQUATOR NEAR 27W. SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 03N BETWEEN 24W-29W. ...DISCUSSION... GULF OF MEXICO... SOUTHWESTERLY FLOW ALOFT PREVAILS OVER THE GULF THIS MORNING WITH AN APPROACHING MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH NOTED ON WATER VAPOR IMAGERY CENTERED OVER NW MEXICO NEAR 29N106W. WITH THE UPPER LEVEL DYNAMICS IN PLACE TO THE WEST...A 1015 MB SURFACE LOW IS ANALYZED OFF THE COAST OF SOUTHERN TEXAS NEAR 27N97W WITH A STATIONARY FRONT EXTENDING EAST TO 28N90W AND SOUTH TO NEAR 25N98W ACROSS INLAND NE MEXICO. THIS DEVELOPING AREA OF LOW PRESSURE IS ACCOMPANIED BY SCATTERED TO NUMEROUS SHOWERS AND ISOLATED TSTMS 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. TO THE SOUTH OF THE LOW...SURFACE TROUGHING EXTENDS OFFSHORE ALONG THE EASTERN MEXICO COAST FROM 23N97W SE TO 18N93W. TO THE EAST ACROSS THE REMAINDER OF THE BASIN...MODERATE TO FRESH E-SE WINDS ARE OCCURRING ON THE SOUTHWESTERN PERIPHERY OF WEAKENING SURFACE RIDGING ANCHORED TO THE NORTHEAST ACROSS THE SW NORTH ATLC REGION. 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 GRADUALLY MOVING 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 MORNING 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 MORNING. 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 26N47W. WITH A VERY PROGRESSIVE PATTERN IN PLACE... THE ONLY BOUNDARY EXTENDING INTO THE DISCUSSION AREA IS A WEAK STATIONARY FRONT ANALYZED FROM 32N52W TO 27N65W THAT BECOMES A SHEAR LINE TO THE NW BAHAMAS NEAR 25N80W. SHALLOW ISOLATED SHOWERS ARE OCCURRING WITHIN 120 NM NORTH OF THE BOUNDARY. OTHERWISE...A 1026 MB HIGH IS CENTERED NEAR 32N71W 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 19N48W THAT SUPPORTS INCREASED MOISTURE AND CLOUDINESS ON THE EASTERN PERIPHERY OF THE LOW FROM 13N-22N BETWEEN 41W-48W. FINALLY...ANOTHER MIDDLE TO UPPER LEVEL LOW IS CENTERED OFF THE COAST OF WEST AFRICA NEAR 23N19W THAT SUPPORTS A 1010 MB LOW CENTERED NEAR 23N17W. 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 INDICATED REDUCED VISIBILITY AND BLOWING DUST. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN