000 AXNT20 KNHC 222350 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE JUN 22 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 2230 UTC... ...SPECIAL FEATURES... A STRONG TROPICAL WAVE IS MOVING THROUGH THE CENTRAL CARIBBEAN EXTENDING FROM TURKS AND CAICOS NEAR 21N73W ACROSS THE WINDWARD PASSAGE TO THE COAST OF COLOMBIA NEAR 11N74W MOVING W NEAR 12 KT. THE WAVE IS ACCOMPANIED BY A LARGE AREA OF DEEP LAYER MOISTURE THAT COVERS THE ENTIRE CENTRAL AND ERN HALF OF THE CARIBBEAN EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. BROAD LOW TO MID-LEVEL CYCLONIC FLOW IS ABOUT THE WAVE. SCATTERED MODERATE/STRONG CONVECTION IS FROM 14N-19N BETWEEN 66W-72W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 14N-21N BETWEEN 72W-78W. THIS LARGE AREA OF ACTIVITY IS EXPECTED TO BRING 4-7 INCHES OF RAIN TO HISPANIOLA. HEAVY RAINFALL IS ALSO POSSIBLE ACROSS PUERTO RICO. ...TROPICAL WAVES... HIGH AMPLITUDE TROPICAL WAVE EXTENDS FROM 16N37W TO 4N40W MOVING W NEAR 20 KT. A DRY LOW-LEVEL VORTICITY CENTER IS AHEAD OF THE WAVE AXIS DRAWING A DRY SAHARAN AIR LAYER ACCOMPANIED BY DUST AROUND THE TOP AND WRN SIDE OF THE WAVE. TOTAL PRECIPITABLE WATER IMAGERY ALSO INDICATES A DRY CIRCULATION ABOUT THE WAVE WITH A PEAK IN DEEP LAYER MOISTURE TO THE E OF THE AXIS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-10N BETWEEN 25W-45W. TROPICAL WAVE EXTENDS ACROSS THE WINDWARD ISLANDS ALONG 61W S OF 15 N MOVING W NEAR 12 KT. THE WAVE COINCIDES WITH A DEEP LAYER MOISTURE MAXIMUM OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. VISIBLE SATELLITE IMAGERY INDICATES LOW-LEVEL CYCLONIC FLOW ABOUT THE WAVE AXIS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 11N-15N BETWEEN 61W-63W. TROPICAL WAVE EXTENDS FROM THE GULF OF MEXICO TO THE NW CARIBBEAN ALONG 29N88W 23N87W 19N85W PREVIOUSLY MOVING WNW NEAR 10 KT. THE WAVE COINCIDES WITH AN AREA OF MODERATE MOISTURE SEEN IN TOTAL PRECIPITABLE WATER IMAGERY. THE NRN PORTION OF THIS WAVE CONTINUES TO BE ABSORBED INTO A WEAKNESS IN THE SURFACE RIDGE ACROSS THE GULF COAST STATES. THE SRN PORTION IS EXPECTED TO MOVE INTO THE BAY OF CAMPECHE AND GET LOST OVER SRN MEXICO. SCATTERED MODERATE/CONVECTION IS ACROSS THE NRN GULF FROM 25N-31N BETWEEN 85W-94W ASSOCIATED WITH THE NRN EXTEND OF THE WAVE AND A SURFACE TROUGH ANALYZED S OF LOUISIANA. THE SRN PORTION OF THE WAVE IS GENERATING SIMILAR ACTIVITY ACROSS THE YUCATAN PENINSULA FROM 19N-22N BETWEEN 87W-91W. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N11W 6N22W 9N37W 5N46W 8N60W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 4N-7N BETWEEN 19W-26W. SIMILAR ACTIVITY IS FROM 8N-11N BETWEEN 54W-57W W OF A SURFACE TROUGH ANALYZED ALONG 53W S OF 13N. ...DISCUSSION... GULF OF MEXICO... A SHORTWAVE UPPER LEVEL TROUGH EXTENDING FROM CENTRAL ALABAMA INTO THE NE GULF SUPPORTS A 1016 MB LOW OVER THE SE LOUISIANA NEAR 30N91W WITH A SURFACE TROUGH EXTENDING FROM THE CENTER TO NEAR 28N92W. A TROPICAL WAVE IS BECOMING EMBEDDED IN THIS SYSTEM. THE COMBINATION OF BOTH FEATURES IS ENHANCING SCATTERED SHOWERS/THUNDERSTORMS ACROSS THE NRN GULF AND GULF COAST STATES FROM 25N-31N BETWEEN 85W-94W CONFIRMED BY LIGHTNING DATA AND RADAR IMAGERY. ISOLATED SHOWERS/THUNDERSTORMS ARE ALSO ACROSS THE WRN FLORIDA PENINSULA DUE TO DAYTIME HEATING AND SEABREEZE CONVERGENCE. AS OF 2100 UTC...A SURFACE TROUGH IS ANALYZED IN THE BAY OF CAMPECHE ALONG 23N92W 17N94W ENHANCING SCATTERED SHOWERS/THUNDERSTORMS FROM 17N-20N BETWEEN 93W-96W. THE TROUGH IS SUPPORTED BY AN UPPER LEVEL LOW DIRECTLY ABOVE IT NEAR 20N95W. THE SRN EXTENT OF THE TROPICAL WAVE IN THE NW CARIBBEAN AND CENTRAL GULF WILL MOST LIKELY MERGE WITH THIS SURFACE TROUGH. THIS SRN EXTENT IS CURRENTLY FLARING UP SHOWERS/THUNDERSTORMS ACROSS THE YUCATAN PENINSULA. ELSEWHERE...A WEAK PRESSURE GRADIENT IS ACROSS THE BASIN MAINTAINING LIGHT TO MODERATE E-SE WINDS. ALOFT...AN UPPER LEVEL RIDGE CENTERED OVER NE TEXAS IS PROVIDING MAINLY NE-E FLOW OVER THE NW GULF ACCOMPANIED BY DRY AIR KEEPING CONDITIONS FAIR. CARIBBEAN SEA... A TROPICAL WAVE EXTENDING FROM THE GULF OF MEXICO INTO THE NW CARIBBEAN IS ENHANCING SHOWERS/THUNDERSTORMS ACROSS THE YUCATAN PENINSULA. DAYTIME HEATING AND SEABREEZE CONVERGENCE IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS ACROSS MUCH OF CUBA. THIS IS FURTHER ENHANCED BY DIFFLUENCE ALOFT BETWEEN AN UPPER LEVEL TROUGH EXTENDING FROM AN UPPER LEVEL LOW OVER THE BAY OF CAMPECHE TO THE NW BAHAMAS...AND AN UPPER LEVEL RIDGE COVERING THE REMAINDER OF THE BASIN. ISOLATED SHOWERS/THUNDERSTORMS ARE ALSO ACROSS CENTRAL AMERICA. A STRONG TROPICAL WAVE EXTENDS FROM TURKS AND CAICOS NEAR 21N73W ACROSS THE WINDWARD PASSAGE TO THE COAST OF COLOMBIA NEAR 11N74W SUPPORTING A LARGE AREA OF SHOWERS/THUNDERSTORMS ACROSS THE NRN CARIBBEAN IMPACTING HISPANIOLA AND PUERTO RICO. SCATTERED MODERATE/STRONG CONVECTION IS FROM 14N-19N BETWEEN 66W-72W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 14N-21N BETWEEN 72W-78W. SEE SPECIAL FEATURES ABOVE ABOVE FOR MORE DETAILS. ALOFT...AN UPPER LEVEL RIDGE COVERS THE MAJORITY OF THE BASIN CENTERED W OF THE LESSER ANTILLES NEAR 15N65W. EXPECT CONTINUED SHOWER ACTIVITY ACROSS MUCH OF THE BASIN AS THE TROPICAL WAVE MOVES WWD. ATLANTIC OCEAN... A FEW ISOLATED SHOWERS/THUNDERSTORMS ARE OFF THE ERN COAST OF FLORIDA AND THE NW/CENTRAL BAHAMAS ENHANCED BY DAYTIME HEATING AND SEABREEZE CONVERGENCE. THIS ACTIVITY IS FURTHER ENHANCED BY DIFFLUENT FLOW ALOFT BETWEEN AN UPPER LEVEL TROUGH EXTENDING FROM THE BAY OF CAMPECHE TO THE NW BAHAMAS AND AN UPPER LEVEL RIDGE EXTENDING FROM THE ERN CARIBBEAN. THE REMAINDER OF THE W ATLC IS INFLUENCED BY DRY AIR ALOFT KEEPING CONDITIONS FAIR. AN ACTIVE CARIBBEAN TROPICAL WAVE EXTENDING FROM TURKS AND CAICOS INTO THE CENTRAL CARIBBEAN IS ENHANCING SCATTERED MODERATE/ISOLATED STRONG CONVECTION S OF 21N BETWEEN 66W-74W. FARTHER E...SURFACE RIDGING DOMINATES ANCHORED BY A PAIR OF 1029 MB HIGHS NEAR 33N39W AND 38N32W PROVIDING GENERALLY FAIR WEATHER ACROSS THE ERN ATLC. A DRY SAHARAN AIR LAYER WRAPS AROUND THE ERN ATLC TROPICAL WAVE ACCOMPANIED BY AFRICAN DUST EXTENDING TO 54W S OF 24N EVIDENT IN THE LAST VISIBLE SATELLITE IMAGES OF THE DAY. ALOFT...AN UPPER LEVEL TROUGH EXTENDS FROM NEAR 37N45W TO 10N45W EMBEDDED BETWEEN TWO UPPER LEVEL RIDGES...CENTERED OVER THE ERN CARIBBEAN AND WRN AFRICA. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON