000 AXNT20 KNHC 231723 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE JUN 23 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 1700 UTC. ...TROPICAL WAVES... A TROPICAL WAVE EXTENDS FROM 15N60W TO 4N62W MOVING W AROUND 15 KT. THIS WAVE COINCIDES WELL WITH A DEEP MOISTURE MAXIMUM SEEN IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE CONVECTION IS FROM 10N-17N BETWEEN 57W-61W. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N15W 7N25W 6N35W 5N44W AND INTO NE BRAZIL NEAR 3N52W. SCATTERED MODERATE CONVECTION IS FROM 7N-10N BETWEEN 14W-17W...FROM 5N-9N BETWEEN 19W-23W...AND FROM 4N-6N BETWEEN 29W-32W. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL DIFFLUENCE BETWEEN AN UPPER LEVEL LOW CENTERED OVER MEXICO NEAR 25N102W AND AN UPPER LEVEL HIGH OVER LOUISIANA IS SUPPORTING A SURFACE TROUGH IN THE SW GULF OF MEXICO EXTENDING FROM 20N96W TO 23N96W. SURFACE CONVERGENCE NEAR THE TROUGH ALONG WITH THE UPPER LEVEL DIFFLUENCE ARE SUPPORTING SCATTERED SHOWERS/ THUNDERSTORMS FROM 21N-26N BETWEEN 94W-97W. A SURFACE TROUGH OVER THE W ATLC IS SUPPORTING A LINE OF HEAVY SHOWERS/THUNDERSTORMS MOVING OVER S FLORIDA AND IS CURRENTLY OVER THE NRN KEYS AND THE STRAITS OF FLORIDA. ACROSS THE N AND CENTRAL GULF...A WEAK 1011 MB SURFACE HIGH NEAR 28N93W DOMINATES BRINGING MAINLY FAIR WEATHER ACROSS THE REMAINDER OF THE GULF. THE SURFACE HIGH HAS UPPER LEVEL SUPPORT FROM THE AFOREMENTIONED UPPER LEVEL HIGH OVER LOUISIANA NEAR 31N92W WHICH IS PROVIDING DRY AIR AND SUBSIDENCE. VARIABLE WINDS OF 5-10 KT PREVAIL ACROSS THE MAJORITY OF THE GULF WITH SLY WINDS OF 10-15 KT W OF 94W. EXPECT A SIMILAR PATTERN OVER THE NEXT FEW DAYS. CARIBBEAN SEA... UPPER LEVEL N-NE FLOW IS DRAWING MODERATELY DRY AIR TO THE NW CARIBBEAN N OF 15N W OF 17W RESULTING IN FAIR WEATHER ACROSS THE CENTRAL AND NW CARIBBEAN. A BROAD UPPER LEVEL RIDGE IS OVER THE CENTRAL AND E CARIBBEAN WHERE MAINLY W UPPER LEVEL FLOW PREVAILS. UPPER LEVEL DIFFLUENCE AT THE BASE OF AN UPPER LEVEL TROUGH OVER THE W ATLC WHICH IS SUPPORTING HEAVY SHOWERS OVER S FLORIDA IS ALSO SUPPORTING ISOLATED SHOWERS/ THUNDERSTORMS OVER CUBA AND HISPANIOLA. UPPER LEVEL DIFFLUENCE BETWEEN AN UPPER LEVEL LOW OVER THE COAST RICA/ NICARAGUA BORDER AND THE BROAD UPPER LEVEL RIDGE IS SUPPORTING A SURFACE LOW OVER THE COSTA RICA/ PANAMA BORDER AS WELL AS A PORTION OF THE ITCZ WHICH HAS PULLED N OF PANAMA AND EXTENDS FROM 9N76W TO 9N81W. SURFACE CONVERGENCE NEAR BOTH OF THESE SURFACE FEATURES IS SUPPORTING ISOLATED SHOWERS/THUNDERSTORMS S OF 13N W OF 77W. ATMOSPHERIC INSTABILITY AND SUPPORT FROM THE TROPICAL WAVE IN THE FAR E CARIBBEAN IS SUPPORTING SCATTERED SHOWERS S OF 16N E OF 70W. EXPECT THE TROPICAL WAVE TO CONTINUE PROPAGATING W ACROSS THE CARIBBEAN. ATLANTIC OCEAN... A DEEP UPPER LEVEL TROUGH OVER THE W ATLC WITH AXIS EXTENDING FROM 32N72W TO 22N73W IS SUPPORTING...A STATIONARY FRONT ENTERING THE DISCUSSION AREA NEAR 32N63W EXTENDING TO 28N65W...A SURFACE TROUGH EXTENDING FROM 31N66W 24N72W 28N79W...AND A SECOND STATIONARY FRONT EXTENDING FROM 28N79W TO 32N83W TO N OF THE DISCUSSION AREA. SURFACE CONVERGENCE NEAR THE SURFACE TROUGH AND UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THE UPPER LEVEL TROUGH ARE SUPPORTING SCATTERED SHOWERS WITHIN 200 NM AHEAD OF THE SURFACE TROUGH AXIS E OF 70W...WITHIN 100 NM EITHER SIDE OF THE TROUGH AXIS BETWEEN 70W-77W...AND NUMEROUS SHOWERS/ SCATTERED THUNDERSTORMS WITHIN 200 NM AHEAD OF THE TROUGH W OF 77W...INCLUDING S FLORIDA AND THE NRN BAHAMAS. THE REMAINDER OF THE ATLC IS UNDER A BROAD SURFACE RIDGE ANCHORED BY A 1027 MB HIGH AT THE EDGE OF THE THE DISCUSSION AREA NEAR 32N41W. IN THE UPPER LEVELS...A STEEP UPPER LEVEL RIDGE IS E OF THE UPPER LEVEL TROUGH IN THE W ATLC EXTENDING FROM 21N64W TO 32N56W TO N OF THE DISCUSSION AREA. AN UPPER LEVEL LOW IS NEAR 24N48W WHICH IS ABSORBED INTO A DEEPER UPPER LEVEL TROUGH OVER THE FAR E ATLC EXTEND FROM 22N29W TO 32N25W TO N OF THE AREA. $$ WALTON