000 AXNT20 KNHC 121728 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT WED AUG 12 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. ...SPECIAL FEATURES... TROPICAL DEPRESSION TWO IS CENTERED NEAR 14.3N 33.8W OR ABOUT 630 MILES...1015 KM...WEST OF THE SOUTHERNMOST CAPE VERDE ISLANDS AT 12/1500 UTC MOVING W AT 11 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SEE LATEST NHC FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 FOR MORE DETAILS. CONVECTION REMAINS TO THE W OF THE LOW LEVEL CENTER WITH LIGHT TO MODERATE SOUTHEASTERLY SHEAR EXPECTED FOR THE NEXT SEVERAL DAYS. SCATTERED MODERATE/ STRONG CONVECTION IS FROM 12N-15N BETWEEN 34W-37W. ...TROPICAL WAVES... TROPICAL WAVE IS INTRODUCED ALONG 18W S OF 17N MOVING W AT 15 KT. SATELLITE IMAGERY AND SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOWED A WELL DEFINED WAVE OFF THE COAST OF WEST AFRICA. UPPER AIR SOUNDINGS FROM DAKAR SENEGAL ALSO DEPICTED WAVE PASSAGE. WIDELY SCATTERED MODERATE CONVECTION IS FROM 6N-16N BETWEEN 15W-25W. TROPICAL WAVE IS ALONG 58W S OF 20N MOVING W 15 KT. THE WAVE IS HAS A WELL DEFINED INVERTED-V LOW LEVEL CLOUD SIGNATURE WITH EMBEDDED SHOWERS AND THUNDERSTORMS. AN SSMI TOTAL PRECIPITABLE WATER MAXIMUM IS ALSO NOTED. WIDELY SCATTERED MODERATE CONVECTION IS FROM 11N-22N BETWEEN 57W-63W. TROPICAL WAVE IS FROM ALONG 67W S OF 21N MOVING W NEAR 12 KT. A BAND OF DRY AIR HAS WRAPPED AROUND THE W SIDE OF THIS WAVE INHIBITING CONVECTION W OF THE WAVE AXIS. WIDELY SCATTERED SHOWERS ARE HOWEVER E OF THE WAVE AXIS FROM 8N-22N BETWEEN 63W-67W. SCATTERED MODERATE CONVECTION IS FROM 11N-13N BETWEEN 65W-66W. TROPICAL WAVE IS ALONG 84W S OF 21N MOVING W 15-20 KT. THE WAVE IS HAS A WELL DEFINED INVERTED-V LOW LEVEL CLOUD SIGNATURE WITH EMBEDDED SHOWERS AND THUNDERSTORMS. AN SSMI TOTAL PRECIPITABLE WATER MAXIMUM IS ALSO NOTED. WIDELY SCATTERED MODERATE CONVECTION IS ALONG THE COAST OF NICARAGUA FROM 11N-14N BETWEEN 82W-85W. SIMILAR CONVECTION IS OVER THE NW CARIBBEAN FROM 16N-20N BETWEEN 82W-90W. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 12N16W 11N24W 14N31W 11N43W 13N56W 13N67W. BESIDES THE CONVECTION THAT WAS MENTIONED IN THE SPECIAL FEATURES AND TROPICAL WAVE SECTIONS...SCATTERED SHOWERS ARE FROM 7N-13N BETWEEN 40W-47W. ...DISCUSSION... GULF OF MEXICO... AS OF 1500 UTC...A SURFACE TROUGH IS OVER THE E GULF FROM THE FLORIDA PANHANDLE AT 31N84W TO THE NW GULF AT 26N93W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 27N-29N BETWEEN 88W-93W. 15 MINUTE LIGHTNING DATA SHOWS FREQUENT LIGHTNING S OF LOUISIANA. ISOLATED SHOWERS ARE ALSO OVER THE N GULF N OF 25N. HIGH PRES RIDGING IS OVER THE S GULF WITH AXIS ALONG 25N. OUTSIDE AREAS OF CONVECTION SURFACE WINDS ARE LIGHT TO VARIABLE ACROSS THE GULF. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE N GULF N OF 25N. AN EMBEDDED UPPER LEVEL LOW IS OVER THE NE GULF CENTERED NEAR 26N87W. ANOTHER UPPER LEVEL LOW IS OVER S MEXICO CENTERED AT 18N98W. SIGNIFICANT UPPER LEVEL MOISTURE COVERS THE ENTIRE AREA. EXPECT...THE SURFACE TROUGH TO MOVE E OVER THE NEXT 24 HOURS WITH CONTINUED CONVECTION. ALSO EXPECT MORE SHOWERS AND THUNDERSTORMS OVER THE N GULF N OF 25N. CARIBBEAN SEA... THREE TROPICAL WAVES ARE AFFECTING THE CARIBBEAN SEA AND CENTRAL AMERICA. SEE ABOVE. MODERATE TRADEWINDS ARE OVER THE AREA. IN ADDITION...A 1008 MB LOW IS OVER E PANAMA NEAR 8N77W. SCATTERED SHOWERS ARE NOTED ON RADAR OVER PUERTO RICO AND HISPANIOLA. SIMILAR SHOWERS ARE OVER JAMAICA FROM 16N-19N BETWEEN 75W-80W. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS OVER THE W CARIBBEAN NEAR 16N83W. AN UPPER LEVEL LOW IS N OF THE LEEWARD ISLANDS NEAR 23N61W. STRONG SUBSIDENCE IS OVER THE CENTRAL CARIBBEAN BETWEEN 70W-80W. EXPECT SHOWERS AND ISOLATED THUNDERSTORMS OVER THE CARIBBEAN DUE TO THE TROPICAL WAVES OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... A HIGH PRES RIDGE AXIS OVER THE CENTRAL AND W ATLANTIC EXTENDS FROM 30N45W TO 25N80W. A 1029 MB HIGH IS CENTERED NEAR THE AZORES AT 42N25W. A RIDGE AXIS EXTENDS SW TO THE CENTRAL ATLANTIC NEAR 30N45W. IN THE UPPER LEVELS...AN UPPER LEVEL RIDGE IS OVER THE W ATLANTIC N OF 20N AND W OF 55W. AN UPPER LEVEL TROUGH IS OVER THE CENTRAL AND E ATLANTIC N OF 22N BETWEEN 25W-55W. A LARGE UPPER LEVEL HIGH IS CENTERED OVER THE TROPICAL ATLANTIC NEAR 16N47W. EXPECT THE TROPICAL WAVES AND SPECIAL FEATURES TO BE THE DOMINATE FEATURES OVER THE NEXT 24 HOURS. $$ MRF/RFB