000 AXNT20 KNHC 170603 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI APR 17 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 0545 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 09N14W SW TO 05N15W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 02S30W TO THE COAST OF NORTHERN BRAZIL NEAR 02S44W. ISOLATED MODERATE CONVECTION IS FROM 07S TO 03N WEST OF 10W. ...DISCUSSION... GULF OF MEXICO... A 1017 MB LOW OVER SOUTH CAROLINA AND GEORGIA ADJACENT WATERS EXTENDS A COLD FRONT SW ACROSS NORTHERN FLORIDA AND ACROSS THE NE GULF FROM 28N82W NW TO SOUTHERN ALABAMA NEAR 30N87W. W OF THE FRONT A SURFACE TROUGH EXTENDS FROM 28N86W TO 27N93W. LOW LEVEL MOISTURE CONVERGENCE ASSOCIATED WITH THE TROUGH ALONG WITH A DIFFLUENT ENVIRONMENT ALOFT ACROSS THE N-NE GULF AND THE SW N ATLC SUPPORTS SCATTERED MODERATE CONVECTION AND TSTMS N OF 27N BETWEEN 86W AND 92W. SCATTERED SHOWERS ARE OVER THE REMAINDER NE GULF AND NORTHERN TO CENTRAL FLORIDA. GOES-GEO COLOR IMAGERY AND SURFACE OBSERVATIONS INDICATE THE PRESENCE OF FOG OVER THE NW GULF N OF 25N W OF 91W. SURFACE RIDGING OVER THE ATLC CONTINUE TO PROVIDE SE WIND FLOW OF 5 TO 10 KT MAINLY S OF 28N. SURFACE RIDGING WILL BE THE DOMINANT FEATURE OVER THE EASTERN BASIN THE NEXT THREE DAYS WHILE LOW PRESSURE WILL CONTINUE W OF 90W. SHOWERS ACROSS THE NORTHERN GULF WILL CONTINUE THROUGH FRIDAY NIGHT. CARIBBEAN SEA... A BROAD SURFACE RIDGE OVER THE ATLC OCEAN EXTENDS TO THE NORTHERN CARIBBEAN WHILE LOWER PRESSURE DOMINATES ELSEWHERE S OF 14N. A SLIGHTLY TIGHTER PRESSURE GRADIENT IS OVER THE CENTRAL CARIBBEAN ASSOCIATED WITH A 1006 MB LOW OVER N COLOMBIA...THUS RESULTING IN TRADES OF 20 TO 25 KT S OF 15N BETWEEN 68W AND 78W...BEING THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA. ELSEWHERE TRADES OF 15 KT DOMINATE. SSMI TPW IMAGERY SHOW SCATTERED PATCHES OF SHALLOW MOISTURE MOVING ACROSS THE NW AND EASTERN BASIN...THUS SUPPORTING CLOUDINESS AND POSSIBLE ISOLATED SHOWERS OVER THE LESSER ANTILLES...CENTRAL AND WESTERN HISPANIOLA AND THE NW CARIBBEAN N OF 17N. ISOLATED SHOWERS ARE ON PANAMA COASTAL WATERS. FAIR WEATHER IS ELSEWHERE BEING SUPPORTED BY DRY AIR SUBSIDENCE FROM ALOFT. NOT SIGNIFICANT CHANGES ARE EXPECTED DURING THE NEXT TWO DAYS. ...HISPANIOLA... A MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM THE SW N ATLC S ACROSS THE ISLAND TO NORTHERN VENEZUELA. SHALLOW MOISTURE ALONG WITH LIFTING PROVIDED BY THE UPPER TROUGH SUPPORT CLOUDINESS WITH POSSIBLE SCATTERED TO ISOLATED SHOWERS...MAINLY FOCUSED OVER HAITI AND THE WINDWARD PASSAGE. SHOWERS ARE EXPECTED TO CONTINUE THROUGH FRIDAY MORNING WHEN A DRY AIRMASS ENTERS THE ISLAND PROVIDING FAIR WEATHER CONDITIONS FOR THE REMAINDER WEEKEND. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL LOW OVER THE NORTH-CENTRAL ATLC EXTENDS A TROUGH TO A BASE N OF 30N...THUS SUPPORTING A SURFACE LOW PRESSURE SYSTEM FROM WHICH A COLD FRONT EXTENDS SW ENTERING THE AREA OF DISCUSSION FROM 32N45W TO 27N61W TO 28N70W WHERE IT TRANSITIONS TO A STATIONARY FRONT NW TO A 1017 MB LOW NEAR 31N78W. A COLD FRONT EXTENDS FROM THIS LOW SW ACROSS NORTHERN FLORIDA. ISOLATED SHOWERS ARE WITHIN 100 NM EITHER SIDE OF THE COLD FRONT. SCATTERED SHOWERS AND TSTMS ARE OVER THE SW N ATLC N OF 25N W OF 75W. SURFACE RIDGING AND FAIR WEATHER DOMINATES ELSEWHERE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR