000 AXNT20 KNHC 251742 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU JUN 25 2009 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...TROPICAL WAVES... A TROPICAL WAVE EXTENDS FROM 13N31W TO 9N32W TO 4N33W MOVING W NEAR 15 KT. THIS WAVE IS ASSOCIATED WITH A RELATIVELY LOW AMPLITUDE MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. THIS WAVE IS ALSO ASSOCIATED WITH LOW LEVEL CYCLONIC CIRCULATION BASED ON THE CIMSS WAVETRAK PRODUCT. SCATTERED MODERATE CONVECTION IS FROM 6N-9N BETWEEN 31W-33W. A TROPICAL WAVE IS ALONG 59W/60W S OF 19N MOVING W NEAR 20 KT. THIS WAVE IS ALSO ASSOCIATED WITH A MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. VISIBLE SATELLITE IMAGERY INDICATES THAT THIS WAVE COINCIDES WITH AN INVERTED-V PATTERN IN THE COVERAGE OF LOW LEVEL CLOUDS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 10N-12N BETWEEN 54W-59W. ALSO...SCATTERED LOW-TOPPED SHOWERS ASSOCIATED WITH THIS WAVE ARE AFFECTING PORTIONS OF THE WINDWARD ISLANDS. A TROPICAL WAVE EXTENDS FROM 21N73W TO 15N75W TO 9N75W MOVING W NEAR 15 KT. THIS WAVE IS ASSOCIATED WITH A WELL-DEFINED MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. THIS WAVE IS ALSO ASSOCIATED WITH LOW LEVEL CYCLONIC CIRCULATION BASED ON THE CIMSS WAVETRAK PRODUCT. STABLE ATMOSPHERIC CONDITIONS BENEATH A BROAD UPPER LEVEL RIDGE OVER THE CENTRAL AND E CARIBBEAN IS INHIBITING DEEP CONVECTION NEAR THIS WAVE. HOWEVER...SCATTERED SHOWERS ARE OCCURRING FROM 15N-19N BETWEEN 71W-78W INCLUDING PORTIONS OF HISPANIOLA AND JAMAICA. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 9N13W 8N25W 6N39W 6N48W 7N59W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 5N-11N BETWEEN 14W-22W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 6N-8N BETWEEN 24W-29W. SCATTERED MODERATE CONVECTION IS FROM 4N-8N BETWEEN 34W-41W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 7N-9N BETWEEN 49W-53W. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL DIVERGENCE ASSOCIATED WITH AN UPPER LEVEL RIDGE OVER MEXICO IS SUPPORTING SCATTERED SHOWERS AND THUNDERSTORMS OVER THE SW GULF S OF 24N W OF 93W. ALSO...ATMOSPHERIC INSTABILITY ASSOCIATED WITH AN UPPER LEVEL TROUGH OVER THE W ATLC AND SE GULF IS RESULTING IN SCATTERED SHOWERS AND THUNDERSTORMS FROM 24N-29N BETWEEN 82W-90W INCLUDING PORTIONS OF THE S FLORIDA PENINSULA. THIS ACTIVITY IS ALSO BEING SUPPORTED BY LOW LEVEL CONVERGENCE NEAR A 1010 MB SURFACE LOW OVER SE LOUISIANA NEAR 31N91W...AS WELL AS LOW LEVEL CONFLUENCE ACROSS PORTIONS OF THE CENTRAL AND E GULF. BETWEEN THE TWO AREAS OF SHOWERS AND THUNDERSTORMS...SUBSIDENCE AND DEEP LAYER DRY AIR ACROSS PORTIONS OF THE NW AND SOUTH CENTRAL GULF ARE RESULTING IN GENERALLY FAIR WEATHER. THIS SUBSIDENCE IS SUPPORTING A 1012 MB SURFACE HIGH OVER THE CENTRAL GULF NEAR 25N89W. CARIBBEAN SEA... A BROAD UPPER LEVEL RIDGE IS AFFECTING MUCH OF THE CENTRAL AND E CARIBBEAN. UPPER LEVEL DIVERGENCE ASSOCIATED WITH THIS RIDGE IS COMBINING WITH DEEP LAYER MOISTURE OVER THE SW CARIBBEAN TO RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS S OF 16N W OF 76W INCLUDING PORTIONS OF NICARAGUA AND PANAMA. ACROSS MUCH OF THE NW AND E CARIBBEAN...DEEP LAYER DRY AIR IS RESULTING IN GENERALLY FAIR WEATHER. NE TO E WINDS OF 15 TO 20 KT ARE OCCURRING ACROSS MUCH OF THE CARIBBEAN. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH OVER THE W ATLC AND SE GULF OF MEXICO IS ASSOCIATED WITH A SURFACE TROUGH EXTENDING FROM 31N68W TO 28N74W 27N79W. LOW LEVEL CONVERGENCE NEAR THE SURFACE TROUGH...AS WELL AS ATMOSPHERIC LIFT IN SOUTHWESTERLY FLOW ALOFT AND UPPER LEVEL MOISTURE...ARE SUPPORTING SCATTERED SHOWERS AND THUNDERSTORMS FROM 25N-30N BETWEEN 62W-78W INCLUDING PORTIONS OF THE NW BAHAMAS. FARTHER TO THE E...GENERALLY FAIR WEATHER IS PRESENT ACROSS MUCH OF THE CENTRAL AND E ATLC...WHERE SUBSIDENCE IS OCCURRING NEAR A BROAD SURFACE RIDGE. THIS SURFACE RIDGE IS ASSOCIATED WITH A 1026 MB SURFACE HIGH NEAR 33N50W AND A 1021 MB SURFACE HIGH NEAR 28N29W. HOWEVER...AN UPPER LEVEL TROUGH N OF 27N BETWEEN 18W-31W IS SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM 31N36W TO 27N41W. LOW LEVEL CONVERGENCE IS SUPPORTING SCATTERED SHOWERS WITHIN 60 NM EITHER SIDE OF THE SURFACE TROUGH. ALSO...ATMOSPHERIC INSTABILITY ASSOCIATED WITH AN UPPER LEVEL LOW NEAR 21N50W IS SUPPORTING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS FROM 19N-23N BETWEEN 53W-57W. ACROSS THE TROPICAL ATLC...AN UPPER LEVEL RIDGE AXIS EXTENDS FROM 15N14W TO 10N28W TO 7N44W. UPPER LEVEL DIVERGENCE ASSOCIATED WITH THE UPPER LEVEL RIDGE IS SUPPORTING CONVECTION ASSOCIATED WITH THE ITCZ AND THE TROPICAL WAVE THAT EXTENDS FROM 13N31W TO 9N32W TO 4N33W. $$ COHEN