000 AXNT20 KNHC 082333 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN MAR 08 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2245 UTC. ...SPECIAL FEATURES... ...GALE WARNING FOR THE SW CARIBBEAN... A GALE WARNING IS IN EFFECT FOR THE COASTAL WATERS OF COLOMBIA FROM 11N TO 13N BETWEEN 74W AND 77W. GALE CONDITIONS WILL CONTINUE THROUGH WED. PLEASE SEE THE LATEST HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL ATLC NEAR 12N16W THEN ALONG 8N13W TO 3N15W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 2N18W 1N24W THEN S OF THE EQUATOR NEAR 26W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM THE ITCZ TO S OF THE EQUATOR BETWEEN 21W-26W. ...DISCUSSION... GULF OF MEXICO... SW FLOW ALOFT CONTINUES TO DOMINATE MOST OF THE GULF WATERS THIS EVENING WITH THE EXCEPTION OF A SHORTWAVE UPPER TROUGH MOVING ACROSS THE LOWER MISSISSIPPI VALLEY ACROSS SE LOUISIANA TO 27N88W IN THE N/CENTRAL GULF. TROPICAL MOISTURE ALOFT IS BEING ADVECTED ACROSS MEXICO AND E TEXAS CLIPPING THE NW GULF WITH SCATTERED TO NUMEROUS SHOWERS W OF LINE FROM VERMILION BAY LOUISIANA TO JUST S OF BROWNSVILLE TEXAS. THE REMNANT DISSIPATING STATIONARY FRONT EXTENDS FROM THE W ATLC ACROSS THE LOWER FLORIDA KEYS TO 25N83W AND SCATTERED SHOWERS WITHIN 75 NM N OF THE FRONT. A LINGERING 1018 MB LOW IS IN THE SW GULF NEAR 19N94W. ISOLATED SHOWERS ARE POSSIBLE SW OF LINE FROM 22N95W TO MEXICO NEAR 18N93W. OTHERWISE...A SURFACE RIDGE DOMINATES THE REMAINDER OF THE GULF THIS EVENING ANCHORED BY A 1027 MB HIGH OVER NE LOUISIANA AND A SERIES OF HIGHS IN THE W ATLC. THE LOW WILL DISSIPATE TONIGHT. A NEW STATIONARY FRONT WILL FORM OVER THE N GULF COASTAL PLAINS MON THEN LIFT N AHEAD OF A WEAK COLD FRONT THAT WILL MOVE OFF THE TEXAS COAST MON NIGHT AND SLOWLY PASS E REACHING FROM SE LOUISIANA TO CENTRAL BAY OF CAMPECHE BY TUE NIGHT. CARIBBEAN SEA... AN UPPER RIDGE IS OVER THE NW CARIBBEAN ALONG 85W S OF 20N COVERING THE AREA W OF 76W. AN UPPER TROUGH EXTENDS FROM AN UPPER LOW IN THE W TROPICAL ATLC INTO THE CARIBBEAN ACROSS THE LESSER ANTILLES NEAR MARTINIQUE TO 17N68W. VERY DRY AND STABLE AIR WITH STRONG SUBSIDENCE ALOFT COVERS THE ENTIRE BASIN. THE SURFACE RIDGE OVER THE ATLC IS PRODUCING A TIGHT PRESSURE GRADIENT OVER THE CARIBBEAN TO GIVE PERSISTENT STRONG EASTERLY TRADE WINDS ACROSS THE BASIN WITH THE WINDS TO GALE FORCE ALONG THE COAST OF COLOMBIA. THESE EASTERLY TRADE WINDS ARE GENERATING PATCHES OF ISOLATED LOW LEVEL SHOWERS ACROSS THE CARIBBEAN MAINLY S OF 20N. THESE TRADE WINDS WILL PERSIST THROUGH THE TUE. THE W TROPICAL ATLC SURFACE TROUGH WILL CLIP THE FAR NE CARIBBEAN MON NIGHT INTO TUE. ...HISPANIOLA... THE EASTERLY TRADE WINDS ARE GENERATING SOME ISOLATED SHOWERS ACROSS PORTIONS OF THE DOMINICAN REPUBLIC THIS EVENING WITH GENERALLY FAIR CONDITIONS ACROSS THE REMAINDER OF THE ISLAND. THIS TREND WILL CONTINUE THROUGH MON. MOISTURE AND THEREFORE SHOWERS WILL INCREASE ON TUE AS THE SURFACE TROUGH THAT IS CURRENTLY E OF THE LESSER ANTILLES MOVES ACROSS THE ISLAND MON NIGHT INTO TUE. ATLANTIC OCEAN... THE SURFACE RIDGE OVER THE SE CONUS AND GULF OF MEXICO EXTENDS INTO THE W ATLC N OF 28N W OF 65W WITH A SERIES OF SURFACE HIGHS JUST N OF THE REGION. A BROAD UPPER TROUGH COVERS THE NW INTO THE N/CENTRAL ATLC SUPPORTING A LINGERING COLD FRONT THAT ENTERS THE CENTRAL ATLC NEAR 32N52W AND EXTENDS ALONG 29N62W TO 27N70W WHERE IT BECOMES A DISSIPATING STATIONARY FRONT ACROSS THE BAHAMAS TO OVER THE FLORIDA KEYS NEAR 25N80W. ISOLATED SHOWERS ARE WITHIN 60 NM N OF THE FRONT. AN UPPER RIDGE EXTENDS FROM E CUBA INTO THE W ATLC ALONG 23N64W TO THE CENTRAL ATLC ALONG 27N42W TO BEYOND 32N33W. A CUTOFF UPPER LOW IS IN THE W TROPICAL ATLC NEAR 18N48W SUPPORTING A SURFACE TROUGH THAT IS RACING AHEAD OF THE UPPER LOW EXTENDING FROM 21N58W TO 14N57W. AN UPPER TROUGH EXTENDS OVER THE E ATLC N OF 20N E OF 26W SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM 23N17W THROUGH A 1009 MB LOW NEAR 25N21W TO 27N24W. VISIBLE SATELLITE IMAGERY SHOWS SAHARAN DUST WRAPPED INTO THIS LOW/TROUGH. THE REMAINDER OF THE ATLC IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1027 MB HIGH NEAR 31N35W. THE NE PORTION OF FRONT WILL MOVE FURTHER E BY MON WHILE THE W PORTION WILL DISSOLVE AS IT LIFTS N OF THE AREA THROUGH MON NIGHT. A SURFACE RIDGE WILL BUILD ALONG 30N TUE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW