000 AXNT20 KNHC 171044 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1030 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 06N10W SW TO 01N18W WHERE THE ITCZ BEGINS AND CONTINUES ALONG THE EQUATOR TO THE COAST OF NORTHERN BRAZIL NEAR 01S50W. SCATTERED MODERATE CONVECTION AND TSTMS ARE FROM 02S TO 03N BETWEEN 18W AND 29W. ISOLATED MODERATE CONVECTION AND TSTMS ARE FROM 07S TO 05N W OF 30W. ...DISCUSSION... GULF OF MEXICO... A 1016 MB LOW OVER GEORGIA ADJACENT WATERS EXTENDS A COLD FRONT SW ACROSS NORTHERN-CENTRAL FLORIDA TO 28N83W WHERE IT TRANSITIONS TO A DISSIPATING STATIONARY FRONT TO 30N88W. W OF THE FRONT A SURFACE TROUGH EXTENDS FROM 29N88W TO 27N95W. LOW LEVEL MOISTURE CONVERGENCE ASSOCIATED WITH THE TROUGH ALONG WITH A DIFFLUENT ENVIRONMENT ALOFT ACROSS THE N-NE GULF SUPPORTS SCATTERED MODERATE CONVECTION AND TSTMS N OF 27N E OF 94W. SCATTERED SHOWERS AND TSTMS ARE OVER THE REMAINDER NW GULF. GOES- GEO COLOR IMAGERY AND SURFACE OBSERVATIONS INDICATE THE PRESENCE OF FOG OVER THE N-NW GULF N OF 26N W OF 88W. SURFACE RIDGING OVER THE ATLC CONTINUE TO PROVIDE SE WIND FLOW OF 10 TO 15 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 1010 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...THE VIRGIN ISLANDS...CENTRAL AND WESTERN HISPANIOLA AND THE NW CARIBBEAN N OF 17N. ISOLATED SHOWERS ARE ON PANAMA AND COSTA RICA 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 30N44W TO 27N57W TO 28N68W. A 1016 MB LOW IS OVER GEORGIA ADJACENT WATERS FROM WHICH A COLD FRONT EXTENDS SW TO CAPE CANAVERAL 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 70W. SURFACE RIDGING AND FAIR WEATHER DOMINATES ELSEWHERE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR