000 AXNT20 KNHC 260542 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN APR 26 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 EXTENDS FROM THE AFRICAN COAST NEAR 8N13W TO 4N22W WHERE THE ITCZ BEGINS AND CONTINUES SOUTH OF THE EQUATOR NEAR 35W TO THE NORTHERN COAST OF BRAZIL NEAR 02S45W. WIDELY SCATTERED MODERATE CONVECTION IS WITHIN 125 NM OF EITHER SIDE OF THE MONSOON TROUGH AND ITCZ. ...DISCUSSION... GULF OF MEXICO... AN MIDDLE TO UPPER LEVEL TROUGH OVER THE OHIO VALLEY SUPPORTS A LOW PRESSURE SYSTEM OVER THE SOUTHEASTERN US. A SURFACE TROUGH TRAILS SOUTHWEST OF THIS LOW AND RESIDES OVER THE NORTHEASTERN GULF FROM NEAR APALACHICOLA TO 29N86W TO 27N91W. CONVECTION HAS WEAKENED IN THE VICINITY OF THIS TROUGH TONIGHT. HOWEVER...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS REMAIN POSSIBLE THROUGH THE REMAINDER OF TONIGHT WITHIN 75 NM OF EITHER SIDE OF THE TROUGH AXIS. CONVECTION OVER MEXICO ASSOCIATED WITH THE SUBTROPICAL JET IS NEARING THE SHORELINE ALONG THE WESTERN GULF. THIS ISOLATED MODERATE CONVECTION MAY AFFECT WATERS FROM 21N TO 23N BETWEEN 95W AND THE COAST OF MEXICO EARLY THIS MORNING. GENERALLY FAIR WEATHER COVERS THE REMAINDER OF THE BASIN WITH ANTICYCLONIC FLOW OF 10 TO 15 KT AROUND WEAK WESTERN ATLC HIGH PRESSURE. MODELS ARE FORECASTING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS THE NORTHERN GULF TODAY WITH A FURTHER INCREASE IN CONVECTION ACROSS THE NORTHERN GULF INTO MONDAY AS A COLD FRONT APPROACHES THE AREA. CARIBBEAN SEA... A 1006 MB LOW OVER N COLOMBIA NEAR 9N74W SUPPORTS WIDELY SCATTERED MODERATE CONVECTION...SOME OF WHICH HAS ENTERED THE SOUTHWEST CARIBBEAN TO 11N BETWEEN THE COLOMBIA COAST AND 78W. THIS CONVECTION SHOULD GRADUALLY DIMINISH OVERNIGHT. OTHERWISE...VERY DRY AND STABLE AIR ALOFT COVERS THE REMAINDER OF THE BASIN WHICH INHIBITS DEEP CONVECTION. ISOLATED SHOWERS IN THE TRADE WIND FLOW CAN BE EXPECTED OVER THE GREATER AND LESSER ANTILLES. 10 TO 15 KT TRADE WINDS COVER MUCH OF THE BASIN...EXCEPT FOR WINDS APPROACHING 25 KT WITHIN 100 NM OF THE NORTHERN COAST OF COLOMBIA...AND WITHIN 100 NM NORTH OF THE COAST OF HONDURAS FROM 85W TO 87W. LITTLE CHANGE IS EXPECTED OVER THE NEXT 24 HOURS. ...HISPANIOLA... ISOLATED TO SCATTERED SHOWERS OVER THE WESTERN HALF OF THE ISLAND MAY CONTINUE OVERNIGHT WITH FAIR WEATHER OVER THE EASTERN HALF OF THE ISLAND. ISOLATED SHOWERS WILL BE POSSIBLE ACROSS THE ISLAND ON SUNDAY...WITH LITTLE CHANGE EXPECTED FOR MONDAY. ATLANTIC OCEAN... THE MIDDLE TO UPPER LEVEL TROUGH OVER THE OHIO VALLEY SUPPORTS LOW PRESSURE OVER NORTH CAROLINA WITH A SURFACE TROUGH MOVING OFFSHORE OVER THE SOUTHWEST NORTHERN ATLC WATERS. CLUSTERS OF MODERATE CONVECTION AND THUNDERSTORMS ASSOCIATED WITH THE SURFACE TROUGH AND LOW EXTENDS OVER OUR AREA OF DISCUSSION NORTH OF 30N BETWEEN 75W AND 79W. THIS CONVECTION IS SPREADING RAPIDLY EASTWARD EARLY THIS MORNING AND WILL AFFECT WATERS N OF 30N EASTWARD TO 70 W THROUGH THE MORNING. WEAK HIGH PRESSURE OF 1015 MB IS OVER THE WESTERN ATLC NEAR 30N68W AND IS DISSIPATING TODAY AS THE SYSTEM EXITING THE US COAST MOVES EASTWARD. FARTHER EAST...A LOW PRESSURE SYSTEM OVER THE NORTH CENTRAL ATLC SUPPORTS A COLD FRONT THAT ENTERS OUR AREA OF DISCUSSION NEAR 32N51W TO 24N66W. SCATTERED MODERATE CONVECTION IS WITHIN 75 NM SE OF THE COLD FRONT N OF 28N. SHOWERS ARE POSSIBLE ALONG AND WITHIN 100 NM SE OF THE REMAINDER OF THE FRONT. A STATIONARY 1022MB HIGH IS CENTERED NEAR 24N33W...WHILE A 1017 MB LOW IS CENTERED NEAR 29N26W. NO CONVECTION IS NOTED WITH THIS LOW. OVER THE NEXT 24 HOURS CONVECTION OFF THE EASTERN US WILL SPREAD EASTWARD TO 60W. ON MONDAY...A COLD FRONT WILL MOVE OVER THE ATLC OFF THE COAST OF NORTH FLORIDA WITH CONVECTION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO