000 AXNT20 KNHC 181157 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI JUN 18 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC... ...TROPICAL WAVES... TROPICAL WAVE IS OVER THE LESSER ANTILLES ALONG 13N62W TO 21N60W. SEVERAL DAYS AGO THIS SYSTEM HAD A HIGHER CHANCE OF DEVELOPING INTO A TROPICAL CYCLONE...BUT DUE TO STRONG UPPER LEVEL WINDS THERE IS CURRENTLY A LOW PROBABILITY OF DEVELOPMENT. HOWEVER...THIS SYSTEM CONTINUES TO BE EMBEDDED IN A LARGE AREA OF ENHANCED DEEP LAYER MOISTURE SUPPORTING WIDESPREAD SHOWER ACTIVITY. NUMEROUS STRONG CONVECTION IS NEAR THE ISLANDS OF GUADELOUPE...DOMINICA...AND MARTINIQUE...FROM 13N-20N BETWEEN 56W-62W. AS THIS SYSTEM MOVES WESTWARD...LOCALLY HEAVY RAINFALL IS POSSIBLE OVER THE LEEWARD ISLANDS NORTH OF 13N...THE VIRGIN ISLANDS...AND PUERTO RICO OVER THE NEXT 12 TO 18 HOURS. TROPICAL WAVE IS ALONG 27W FROM 3N TO 11N MOVING W 10-15 KT. SATELLITE IMAGERY DEPICTS SLIGHT CYCLONIC FLOW ALONG THE NORTHERN HALF OF THE WAVE AXIS. THE WAVE LIES WITHIN AN AREA OF MAXIMUM DEEP LAYER MOISTURE AS SEEN ON THE TOTAL PRECIPITABLE WATER IMAGERY...WHICH ALSO COINCIDES WITH A NWD CLEARING DUR TO SAHARAN AIR LAYER. ISOLATED CLUSTERS OF MODERATE CONVECTION ARE FROM 4N TO 10N BETWEEN 22W AND 32W. TROPICAL WAVE IS ALONG 46W FROM 1N TO 10N MOVING W NEAR 15 KT. THE WAVE COINCIDES WITH A DEEP LAYER MOISTURE MAXIMUM EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED STRONG CONVECTION IS FROM 4N-12N BETWEEN 40W-50W. TROPICAL WAVE IS OVER NORTHERN COLOMBIA ALONG 74W SOUTH OF 15N MOVING W NEAR 15 KT. THE WAVE CONTINUES TO TRACK ALONG AN AREA OF ENHANCED MOISTURE IN TOTAL PRECIPITABLE WATER IMAGERY. HOWEVER...DRY AIR TO THE N OF THIS FEATURE SUPPRESS THE WAVE CONVECTION. CURRENTLY ISOLATED SHOWERS/THUNDERSTORMS ARE WHITING 80 NM OFF THE COAST OF NORTH AND NORTHWEST COLOMBIA. STRONGER CONVECTION IS FOUND INLAND OVER NORTHERN COLOMBIA FROM 6N-10N BETWEEN 73W-77W. CONVECTION ASSOCIATED WITH THIS WAVE WILL IMPACT THE FAR SW CARIBBEAN AS IT MOVES WWD UNDER AN UPPER LEVEL TROUGH CURRENTLY ACROSS THE CENTRAL CARIBBEAN. ...ITCZ... ITCZ AXIS IS ANALYZED FROM THE NORTHERN SIERRA LEONE COAST OVER WEST AFRICA NEAR 9N13W WESTWARD ALONG 6N20W 7N30W 5N40W 8N50W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 80 NM ON EITHER SIDE OF THE ITCZ AXIS BETWEEN 33W-40W. A SURFACE TROUGH IS EMBEDDED IN THE ITCZ ALONG 52W S OF 8N COINCIDING WITH A BROAD AREA OF CYCLONIC FLOW. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 200 NM THE COASTS OF GUYANA..SURINAME...AND FRENCH GUIANA. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL RIDGE OF HIGH PRESSURE IS PRESENT ACROSS THE GULF...SUPPORTING A SURFACE 1018 MB HIGH CENTERED NEAR 27N87W. HOWEVER...A WEAK UPPER LEVEL TROUGH CONTINUES TO IMPACT THE FAR NE GULF...SUPPORTING A COASTAL TROUGH ALONG THE WESTERN FLORIDA PENINSULA...ALABAMA...MISSISSIPPI...AND EASTERN LOUISIANA... PRODUCING SCATTERED SHOWERS/THUNDERSTORMS...SOME LOCALLY HEAVY...WITHIN 70 NM OFF THE COAST OF THESE STATES. A SECOND SURFACE TROUGH IS OVER THE BAY OF CAMPECHE FROM 22N92W TO 18N94W. SCATTERED SHOWERS/THUNDERSTORMS ARE SOUTH OF 20N. WEATHER CONDITIONS ELSEWHERE ARE DOMINATED BY THE UPPER LEVEL RIDGE. CARIBBEAN SEA... AN UPPER LEVEL TROUGH CONTINUES TO COVER THE WRN HALF OF THE CARIBBEAN. UPPER LEVEL DIFFLUENCE AROUND THE BASE OF THE TROUGH IS ENHANCING SHOWERS/THUNDERSTORMS ACROSS THE FAR SW CARIBBEAN S OF 14N W OF 75W AFFECTING THE COASTAL WATERS OF NORTHERN COLOMBIA...PANAMA...COSTA RICA...AND NICARAGUA. THE REMAINDER OF THE WRN CARIBBEAN IS EXPERIENCING GENERALLY FAIR WEATHER UNDER THE INFLUENCE OF DRY AIR ALOFT. A TROPICAL WAVE IS MOVING OVER NORTHERN COLOMBIA ALONG 74W SOUTH OF 15N. SEE TROPICAL WAVE SECTION ABOVE FOR MORE DETAILS REGARDING THIS WAVE. A FAIRLY STRONG TROPICAL WAVE IS MOVING OVER THE LEEWARD ISLANDS NORTH OF 13N BRINGING MODERATE TO ISOLATED STRONG CONVECTION TO THIS REGION. MORE DETAILS ON THIS FEATURE CAN BE FOUND IN THE TROPICAL WAVE SECTION. ATLANTIC OCEAN... A WEAK UPPER LEVEL TROUGH OVER THE FAR WESTERN ATLANTIC IS ENHANCING ISOLATED SHOWERS/THUNDERSTORMS BETWEEN THE BAHAMAS AND THE FLORIDA PENINSULA NORTH OF 24N. THE REMAINDER OF THE W ATLC IS INFLUENCED BY DRY AIR ALOFT AROUND AN UPPER LEVEL RIDGE KEEPING CONDITIONS FAIR NORTH OF 22 WEST OF 50W. AN UPPER LEVEL TROUGH TO THE NE OF THE UPPER RIDGE SUPPORTS A STATIONARY FRONT THAT LINES THE DISCUSSION AREA ALONG 30N BETWEEN 40W-45W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 30 NM EITHER SIDE OF THE AXIS. A TROPICAL WAVE IS ANALYZED ALONG 62W OVER THE THE LEEWARD ISLANDS. NUMEROUS AREAS OF STRONG CONVECTION ARE FROM 13N-22N BETWEEN 56W-61W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION EXPANDS TO 22N BETWEEN 55W-63W. SEE TROPICAL WAVE SECTION ABOVE FOR MORE DETAILS ON THIS SYSTEM. SURFACE RIDGING DOMINATES ELSEWHERE ACROSS THE CENTRAL AND EASTERN ATLC...PROVIDING GENERALLY FAIR WEATHER ACROSS THESE REGIONS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA