000 AXNT20 KNHC 150535 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST THU JAN 15 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. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH CROSS THE COAST OF GUINEA NEAR 09N14W AND CONTINUES TO 05N20W WHERE IT TRANSITIONS TO THE ITCZ. THE ITCZ REACHES FORM 05N20W TO 03N25W...THE WESTWARD TO 02N40W AND THEN TO THE AMAZON RIVER DELTA NEAR 00N50W. SCATTERED MODERATE CONVECTION IS NOTED FROM 01N TO 03N BETWEEN 15W AND 25W. ADDITIONAL SCATTERED MODERATE CONVECTION IS NOTED FROM 05N TO 07N BETWEEN 35W AND 40W. ...DISCUSSION... GULF OF MEXICO... A CUTOFF UPPER LOW OVER THE FOUR CORNERS AREA IN THE SW UNITED STATES IS OPENING INTO A TROUGH AND SHIFTING EASTWARD INTO THE SOUTHERLY PLAINS THIS MORNING. THIS WILL PROVIDE REINFORCEMENT TO A STALLED AND WEAK FRONTAL BOUNDARY DRAPED ACROSS THE CENTRAL AND SOUTHWEST GULF AT 00 UTC...FROM 26N85W TO A WEAK 1017 MB LOW PRES NEAR 24N95W...THEN SOUTHWARD TO 18N93W. COPIOUS MID AND HIGH LEVEL CLOUDINESS CONTINUES TO MOVE FROM THE EASTERN PACIFIC ACROSS MEXICO AND INTO THE GULF OF MEXICO N OF 22N. FOG...DRIZZLE AND LOW CEILINGS ARE NOTED ALONG THE TEXAS AND MEXICAN COASTLINES WITH 4 TO 6 NM IN FOG OBSERVED AT OFFSHORE PLATFORMS IN THE NW GULF. A FEW SHOWERS ARE NOTED ON COASTAL RADAR OFF LOUISIANA AND MISSISSIPPI AHEAD OF THE APPROACHING UPPER TROUGH...SPREADING EASTWARD THROUGH THIS AFTERNOON. NORTHERLY WINDS PERSIST ALONG THE MEXICAN COAST...BUT GENERALLY ONLY 15 TO 20 KT SO FAR THIS MORNING. THIS IS EXPECTED TO INCREASE LATER TODAY AS THE UPPER TROUGH MOVES INTO THE LOWER MISSISSIPPI VALLEY FOLLOWED BY BUILDING HIGH PRES AT THE SURFACE OVER THE SOUTHERN PLAINS AND NORTHERN MEXICO. ELSEWHERE THE WEAK LOW AND THE REINFORCED FRONT WILL SHIFT EASTWARD ACROSS THE GULF THROUGH TONIGHT AND EARLY FRIDAY ACCOMPANIED BY FRESH NORTHERLY FLOW AND DRIER AIR OVER THE NORTHERN GULF. CARIBBEAN SEA... AN UPPER LEVEL TROUGH EXTENDING FROM PUERTO RICO TO THE SW CARIBBEAN IS BECOMING LESS AMPLIFIED AS IT MOVES ACROSS THE CENTRAL AND EASTERN CARIBBEAN. THE MAIN IMPACT OF THE TROUGH ALONG WITH A STRONGER IMPULSE FARTHER NORTH IS TO WEAKEN AND DISPLACE THE SUBTROPICAL RIDGE N OF THE AREA...ALLOWING TRADE WIND FLOW FROM THE TROPICAL N ATLC WATERS W OF 55W THROUGH THE CENTRAL CARIBBEAN TO DIMINISH. REMOTE SENSED SCATTEROMETER DATA AND IN-SITU BUOY OBSERVATIONS INDICATE GENERALLY MODERATE TRADE WINDS OVERALL WITH FRESH TRADES PERSISTING ALONG MOST OF THE COASTLINE OF SOUTH AMERICA. GENERALLY LIGHT TO MODERATE NE WINDS PERSIST OVER THE NW CARIBBEAN...ALTHOUGH SHIP OBSERVATIONS INDICATE LOCALLY ENHANCED WINDS OFF BELIZE. IN ADDITION...WHILE NO RECENT OBSERVATIONS ARE AVAILABLE FROM THE CENTRAL COAST OF COLOMBIA...IT IS LIKELY THAT FRESH TO STRONG TRADE WINDS PERSIST THROUGH THE OVERNIGHT HOURS. A FEW TRADE WINDS SHOWERS PERSIST ACROSS THE LEEWARD AND WINDWARD ISLANDS AS NOTED IN REGIONAL RADAR IMAGERY...BUT THIS HAS DIMINISHED FROM THE LAST COUPLE OF DAYS AS TRADE WIND CONVERGENCE HAS WEAKENED. LITTLE CHANGE IS EXPECTED OVER THE NEXT 24 TO 48 HOURS. ...HISPANIOLA... DEEP LAYER MOISTURE WILL DIMINISH TODAY AS THE MID LEVELS OF THE ATMOSPHERE BECOME DRIER IN THE WAKE OF AN UPPER LEVEL TROUGH THAT MOVE ACROSS THE REGION IN THE PAST COUPLE OF DAYS. THE DRIER AND MORE STABLE AIR IN CONJUNCTION WITH DIMINISHED TRADE WINDS WILL ALLOW ONLY ISOLATED SHOWERS ON EASTERN EXPOSURES THROUGH EARLY FRI. ATLANTIC OCEAN... A SHORT WAVE TROUGH MOVING OFF THE EASTERN SEABOARD IS SUPPORTING SHOWERS AND THUNDERSTORMS ALONG AN ASSOCIATED COLD FRONT REACHING FROM 31N70W TO THE CENTRAL BAHAMAS AND STRAITS OF FLORIDA. THE SUBTROPICAL RIDGE...ANCHORED BY 1032 MB SURFACE HIGH PRES NEAR 31N38W...IS SHIFTING EASTWARD AHEAD OF THE DEEP LAYER TROUGH. VARIOUS ASCAT SATELLITE PASSES OVER THE PAST SEVERAL HOURS INDICATE FRESH TO STRONG TRADE WINDS PERSISTING S OF 25N E OF 50W. OVER THE NEXT 24 HOURS...EXPECT FOR THE COLD FRONT TO CONTINUE MOVING E WHILE WEAKENING AND FOR THE HIGH PRESSURE OVER THE E ATLANTIC TO DRIFT NE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ CHRISTENSEN