000 AXNT20 KNHC 232345 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... A TROPICAL WAVE EXTENDS FROM 16N62W NEAR GUADELOUPE TO 7N63W OVER ERN VENEZUELA MOVING W AROUND AT 15 KT. THIS WAVE COINCIDES WITH A DEEP LAYER MOISTURE MAXIMUM AS OBSERVED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. THE DEEP MOISTURE ASSOCIATED WITH THE WAVE COVERS THE ERN CARIBBEAN E OF 65W BRINGING LOCALLY HEAVY AMOUNTS OF RAINFALL TO THE LESSER ANTILLES S OF 17N. SCATTERED MODERATE CONVECTION IS CONCENTRATED FROM 13N-15N BETWEEN 60W-64W. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N14W 5N33W 5N44W AND INTO NE BRAZIL NEAR 3N51W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS OVER AND ALONG THE W AFRICA COAST FROM 13N-18N BETWEEN 14W-18W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 20W-38W. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL DIFFLUENCE BETWEEN A WEAK UPPER LEVEL LOW CENTERED OVER N/CENTRAL MEXICO NEAR 25N102W AND A BROAD UPPER LEVEL HIGH COVERING A MAJORITY OF THE GULF CENTERED OVER SWRN LOUISIANA IS SUPPORTING A 1009 MB SURFACE LOW IN THE SW GULF OF MEXICO NEAR 22N96W. A 1630 UTC ASCAT PASS CONFIRMS SLY WINDS UP TO 25 KT AND THIS SURFACE CONVERGENCE ON THE ERN SIDE OF THE LOW ALONG WITH THE UPPER LEVEL DIFFLUENCE ARE SUPPORTING SCATTERED SHOWERS AND TSTMS FROM 21N-26N BETWEEN 94W-98W. A SURFACE TROUGH OVER THE W ATLC EXTENDS ACROSS NE FLORIDA AND IS SUPPORTING SCATTERED SHOWERS AND TSTMS ACROSS FLORIDA AND THE NE GULF WATERS NE OF A LINE FROM KEY WEST FLORIDA TO MOBILE BAY. THIS ACTIVITY WILL CONTINUE MOVING SWD OVER THE FAR E GULF AND STRAITS OF FLORIDA. IN BETWEEN THE TWO AFOREMENTIONED SURFACE FEATURES IMPACTING THE GULF...A WEAK 1013 MB SURFACE HIGH NEAR 28N93W AND NARROW RIDGE EXTENDING FROM GALVESTON TEXAS TO THE YUCATAN CHANNEL IS BRINING MAINLY FAIR WEATHER ACROSS THE REMAINDER OF THE GULF. CARIBBEAN SEA... UPPER LEVEL N-NE FLOW IS DRAWING MODERATELY DRY AIR FROM THE CENTRAL GULF OF MEXICO ACROSS THE NW CARIBBEAN N OF 15N W OF 83W RESULTING IN FAIR WEATHER AND A FEW PASSING HIGH CLOUDS ACROSS THE NW CARIBBEAN. A BROAD UPPER LEVEL RIDGE IS OVER THE CENTRAL AND ERN CARIBBEAN WHERE MAINLY WLY UPPER LEVEL FLOW PREVAILS. UPPER LEVEL DIFFLUENCE AT THE BASE OF AN UPPER LEVEL TROUGH OVER THE W ATLC IS SUPPORTING SCATTERED SHOWERS AND ISOLATED TSTMS OVER CUBA AND HISPANIOLA...INCLUDING THE NEARBY COASTAL WATERS N OF 19N BETWEEN 70W-83W. THE BROAD UPPER LEVEL RIDGE ACROSS THE SRN CARIBBEAN IS PROVIDING AN DIFFLUENT PATTERN TO SUPPORT SCATTERED SHOWERS AND TSTMS ACROSS THE SW CARIBBEAN S OF 14N W OF 77W...INCLUDING INTERIOR PORTIONS OF PANAMA AND COSTA RICA. CLOSE PROXIMITY TO THE E PACIFIC ITCZ AXIS ALONG 8-9N IS ALSO A CONTRIBUTING FACTOR SUSTAINING THIS ACTIVITY. ALSO OF NOTE IS THE TROPICAL WAVE LOCATED IN THE ERN CARIBBEAN MOVING WWD. SEE ABOVE FOR MORE DETAILS. ATLANTIC OCEAN... A DEEP LAYER UPPER LEVEL TROUGH IS OVER THE W ATLC WITH AN UPPER LOW CENTERED NEAR 33N71W. THIS UPPER LEVEL FEATURE SUPPORTS A SURFACE TROUGH ALONG 31N67W 27N70W 25N76W TO INLAND OVER THE FLORIDA COAST NEAR CAPE CANAVERAL. LOW-LEVEL SURFACE CONVERGENCE SOUTH AND EAST OF THE SURFACE TROUGH AND AN AREA OF UPPER LEVEL DIFFLUENCE LOCATED E OF THE UPPER LEVEL TROUGH BETWEEN 60W-68W ARE SUPPORTING SCATTERED SHOWERS AND TSTMS FROM 21N TO BEYOND 32N BETWEEN 61W-67W AND WITHIN 300 NM SOUTH OF THE SURFACE TROUGH BETWEEN 67W-81W. THIS INCLUDES THE BAHAMAS...TURKS AND CAICOS ISLANDS AND PORTIONS OF THE GREATER ANTILLES. THE MOST CONCENTRATED AREA OF SCATTERED STRONG CONVECTION IS FROM 23N-28N BETWEEN 62W-67W. THE REMAINDER OF THE ATLC IS UNDER A BROAD SURFACE RIDGE ANCHORED BY A 1026 MB HIGH CENTERED NEAR 31N43W. IN THE UPPER LEVELS ACROSS THE CENTRAL AND E ATLC...GENERALLY WLY FLOW DOMINATES S OF 22N WITH MIDDLE TO UPPER LEVEL MOISTURE AND POSSIBLE SCATTERED SHOWERS...DUE TO THE TROPICAL WAVE IN THE ERN CARIBBEAN...STREAMING ACROSS THE CENTRAL ATLC FROM 12N-17N BETWEEN 45W-62W. $$ HUFFMAN