000 AXNT20 KNHC 271804 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON APR 27 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS FROM THE AFRICA INTO THE TROPICAL ATLC NEAR 07N12W AND EXTENDS ALONG 03N15W TO 3N21W WHERE THE ITCZ BEGINS AND CONTINUES TO 02N33W 01N40W TO THE NORTHERN COAST OF BRAZIL NEAR 50W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 01N TO 05N BETWEEN 10W AND 29W. SIMILAR CONVECTION IS OFF THE COAST OF BRAZIL FROM 02S TO 02N W OF 45W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL LOW NEAR NOVA SCOTIA AND ASSOCIATED TROUGHING CONTINUES TO SUPPORT A LOW PRESSURE SYSTEM OVER THE WESTERN ATLC FROM WHICH A COLD FRONT EXTENDS ENTERING THE SW N ATLC WATERS...NORTHERN FLORIDA AND THE NE GULF FROM 29N82W NW TO SE LOUISIANA. A BROAD UPPER RIDGE ANCHORED IN THE CARIBBEAN DOMINATES THE GULF WATERS WITH SW FLOW ALOFT ADVECTING TROPICAL MOISTURE ACROSS MEXICO AND THE NORTHERN GULF. ABUNDANT LOW LEVEL MOISTURE OVER THE NORTHERN GULF ALONG A DIFFLUENT ENVIRONMENT ALOFT SUPPORTS HEAVY SHOWERS AND TSTMS ASSOCIATED WITH A SQUALL LINE MOVING ALONG SOUTHERN ALABAMA...SOUTHERN MISSISSIPPI TO SE LOUISIANA...EXTENDING TO ADJACENT WATERS N OF 28N. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE OVER THE REMAINDER NE GULF WITHIN 50 NM OF THE COLD FRONT. A MIDDLE TO UPPER LEVEL LOW OVER NW TEXAS SUPPORTS A BROAD SURFACE LOW PRESSURE SYSTEM ANCHORED BY A 1001 MB LOW OVER THE NW GULF NEAR 25N95W. A SECOND LOW PRESSURE CENTER ANCHORED OVER CENTRAL TEXAS EXTENDS A COLD FRONT OVER THE NW BASIN ALONG 28N96W TO BROWNSVILLE TEXAS TO INLAND MEXICO. SEA FOG IS BEING REPORTED IN THIS REGION OF THE GULF N OF 26N W OF 90W...COINCIDING GOES-13 IFR MEDIUM TO HIGH FOG PROBABILITIES. WINDS MAINLY FROM THE S-SE OF 10 TO 15 KT DOMINATES ACROSS THE BASIN S OF 27N. WINDS OF 20 TO 30 KT ARE BEING REPORTED OVER THE NORTHERN GULF WATERS IN THE VICINITY OF THE SQUALL LINE. THE COLD FRONT OVER THE NE GULF WILL MOVE TO THE SOUTHERN FLORIDA PENINSULA AND ACROSS THE GULF EASTERN BASIN THROUGH TONIGHT WHEN IT STARTS RETREATING AS A WARM FRONT. THE LOW OVER THE WESTERN BASIN WILL DRIFT N AND THEN EAST ALONG THE NORTHERN GULF...REACHING THE FLORIDA PANHANDLE WED MORNING WITH ASSOCIATED COLD FRONT EXTENDING TO THE NORTHERN YUCATAN PENINSULA. CARIBBEAN SEA... SURFACE LOW PRESSURE DOMINATES ACROSS THE BASIN WHILE MIDDLE TO UPPER LEVEL RIDGING PREVAILS WITH STRONG DRY AIR SUBSIDENCE SUPPORTING STABLE CONDITIONS AND FAIR WEATHER. SSMI TPW IMAGERY SHOW ABUNDANT MOISTURE OVER THE SW BASIN ASSOCIATED WITH A 1006 MB LOW PRESSURE CENTER OVER NORTHERN COLOMBIA...HOWEVER NO SHOWERS ARE OBSERVED IN THIS REGION. SCATTERED PATCHES OF SHALLOW MOISTURE ARE OVER THE CENTRAL AND EASTERN BASIN...POSSIBLY ENHANCING ISOLATED SHOWERS THIS AFTERNOON. SCATTEROMETER DATA SHOW TRADES OF 10 TO 15 KT DOMINATING THE BASIN...EXCEPT FOR THE FAR WESTERN CARIBBEAN W OF 83W AND S OF 15N BETWEEN 68W AND 75W WHERE 20 KT WINDS ARE BEING REPORTED. SURFACE RIDGING OVER THE ATLC WILL EXTEND OVER THE EASTERN BASIN THE NEXT TWO DAYS. THE TAIL OF THE COLD FRONT CURRENTLY OVER THE NW GULF OF MEXICO WILL REACH NW CARIBBEAN WATERS BY WED AFTERNOON. ...HISPANIOLA... SKIES REMAIN CLEAR ACROSS THE ISLAND AS MIDDLE TO UPPER RIDGING WITH STRONG SUBSIDENCE CONTINUES TO PREVAIL ACROSS THE CARIBBEAN. SCATTERED PATCHES OF SHALLOW MOISTURE OVER SOUTHERN HAITI AND EASTERN DOMINICAN REPUBLIC MAY ENHANCE ISOLATED SHOWERS LATER THIS AFTERNOON. NO MAJOR CHANGES EXPECTED DURING THE NEXT TWO DAYS. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL LOW NEAR NOVA SCOTIA AND ASSOCIATED TROUGHING CONTINUES TO SUPPORT A LOW PRESSURE SYSTEM OVER THE WESTERN ATLC FROM WHICH A COLD FRONT EXTENDS ENTERING THE SW N ATLC WATERS ALONG 30N66W TO 28N80W...ACROSS NORTHERN FLORIDA AND THE NE GULF FROM 29N82W NW TO SE LOUISIANA. ISOLATED SHOWERS ARE WITHIN 50 NM EITHER SIDE OF THE FRONT. AHEAD OF IT...A SURFACE TROUGH IS ANALYZED FROM 29N58W TO 27N72W WITH SCATTERED HEAVY SHOWERS AND TSTMS FROM 25N TO 29N BETWEEN 55W AND 72W. ANOTHER SURFACE TROUGH IS FROM 33N47W TO 27N52W. SCATTERED MODERATE CONVECTION AND TSTMS ARE WITHIN 275 NM AHEAD OF ITS AXIS. A 1019 MB DISSIPATING LOW PRESSURE CENTER IS NEAR 27N25W WITH NO CONVECTION ASSOCIATED WITH IT. SURFACE RIDGING AND FAIR WEATHER DOMINATES ELSEWHERE ACROSS THE ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR