000 AXNT20 KNHC 172341 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SAT APR 17 2010 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC... ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 7N10W 4N16W 2N32W TO INLAND OVER SOUTH AMERICA NEAR 1N50W. NUMEROUS STRONG CONVECTING IS INLAND OVER ALL OF LIBERIA...SE IVORY COAST...SW GUINEA OF W AFRICA... AND WITHIN 60 NM ALONG THE COAST OF LIBERIA. SCATTERED MODERATE/ STRONG CONVECTION IS WITHIN 75 NM N AND 30 NM S OF THE ITCZ FROM 21W-30W. CLUSTERS OF SIMILAR CONVECTION ARE FROM THE EQUATOR TO 2N BETWEEN 15W-33W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM THE ITCZ TO 6N BETWEEN 40W-51W. ...DISCUSSION... GULF OF MEXICO... AS OF 17/2100 UTC...A NEWLY DEVELOPED SURFACE TROUGH EXTENDS OVER THE SE GULF FROM 24N85W TO 27N88W WITH SCATTERED SHOWERS WITHIN 60/75 NM EITHER SIDE OF THE TROUGH AXIS. OTHERWISE...A WEAK SURFACE RIDGE IS OVER THE N GULF ANCHORED WELL N OF THE REGION. AN UPPER TROUGH EXTENDS FROM E TEXAS ALONG 94W TO A WEAK UPPER LOW NEAR 23N92W CONTINUING TO OVER THE YUCATAN PENINSULA NEAR 19N89W. AN UPPER RIDGE OVER THE CARIBBEAN EXTENDS A RIDGE AXIS OFF THE E COAST OF THE FLORIDA PENINSULA AND THUS PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 20N TO INLAND OVER THE YUCATAN AND THROUGH THE YUCATAN CHANNEL BETWEEN 85W-89W. A SIMILAR SCENARIO IS OVER THE W GULF WITH THE UPPER RIDGE AXIS OVER MEXICO AND GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 22N W OF 94W TO INLAND OVER MEXICO AND TEXAS. CARIBBEAN SEA... A WEAKENING SURFACE TROUGH OVER THE NW CARIBBEAN EXTENDING ALONG 86W S OF 20N TO THE COAST OF HONDURAS. A WEAK SURFACE RIDGE OVER THE W ATLC IS GIVING THE CARIBBEAN MODERATE EASTERLY TRADE WINDS TONIGHT. A BROAD UPPER RIDGE DOMINATES THE CARIBBEAN ANCHORED IN THE DEEP TROPICS GIVING THE AREA SW WINDS ALOFT. THIS IS DRAWING UPPER LEVEL MOISTURE AND COUPLED WITH THE ABUNDANCE OF LOW LEVEL MOISTURE IS GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 150 NM OF LINE FROM OVER HONDURAS/NICARAGUA NEAR 15N84W TO ACROSS CUBA NEAR 21N78W. SIMILAR ACTIVITY IS N OF 20N W OF 85W TO OVER THE YUCATAN AND THROUGH THE YUCATAN CHANNEL INTO THE GULF OF MEXICO. BROKEN/OVERCAST HIGH LEVEL DEBRIS CLOUDS COVER MOST OF THE SW CARIBBEAN S OF 14N W OF 74W. THE REMAINDER OF THE CARIBBEAN IS COVERED IN SCATTERED/BROKEN LOW LEVEL CLOUDS WITH ISOLATED SHOWERS USHERED IN ON THE EASTERLY TRADE WINDS. ATLANTIC OCEAN... AN UPPER RIDGE EXTENDS FROM THE CARIBBEAN ACROSS HAITI OFF THE E COAST OF FLORIDA TO NEAR 32N79W PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS W OF A LINE FROM HAITI ACROSS THE TURKS AND CAICOS TO 32N78W TO JUST INLAND OVER THE FLORIDA PENINSULA. SURFACE RIDGE COVERS THE REMAINDER OF THE W ATLC ANCHORED BY A 1022 MB HIGH NEAR 28N66W. AN UPPER TROUGH IS OVER THE CENTRAL ATLC N OF 23N BETWEEN 30W-55W SUPPORTING A COLD FRONT EXTENDING THROUGH 32N34W ALONG 24N39W TO 17N49W BECOMING A SURFACE TROUGH TO E OF BARBADOS NEAR 14N58W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 120 NM OF LINE FROM 24N35W TO BEYOND 32N27W. A RE-ENFORCING COLD FRONT IS TO THE W ENTERING THE REGION NEAR 32N38W EXTENDING ALONG 26N42W TO 23N51W DISSIPATING TO 23N58W WITH NO ASSOCIATED SHOWER ACTIVITY. A WEAK 1019 MB HIGH IS IN THE E ATLC SW OF THE CANARY ISLANDS NEAR 26N22W. A BROAD UPPER RIDGE COVERS THE TROPICAL ATLC AND THE CARIBBEAN ANCHORED NEAR 9N37W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALLACE