000 AXNT20 KNHC 082338 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU OCT 08 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. ...SPECIAL FEATURES... TROPICAL DEPRESSION HENRI IS CENTERED NEAR 20.4N 62.2W AT 08/2100 UTC...OR ABOUT 165 MILES...260 KM...NORTH-NORTHEAST OF THE NORTHERN LEEWARD ISLANDS MOVING NW AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1012 MB. MAXIMUM SUSTAINED WIND SPEED IS 25 KT WITH GUSTS TO 35 KT. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM OF THE CENTER. SEE THE LAST NHC FORECAST/ADVISORY FOR HENRI UNDER AWIPS/WMO HEADERS MIATCMAT5/ WTNT25 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS S OF THE CAPE VERDE ISLANDS ALONG 23W S OF 15N MOVING W NEAR 15 KT. LOW-LEVEL SATELLITE DERIVED WINDS SHOW CYCLONIC CURVATURE S OF 13N ALONG THE WAVE AXIS. A MAXIMUM IN DEEP LAYER MOISTURE IS OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY...HOWEVER SAHARAN DUST IS SUPPRESSING CONVECTION AROUND THE WAVE. DUST AND DRY AIR IS N OF 10N E OF 30W TO THE W AFRICA COAST. ISOLATED SHOWERS DO MANAGE TO BE ALONG THE WAVE AXIS FROM 7N-14N BETWEEN 20W-26W. TROPICAL WAVE IS ALONG 57W S OF 15N MOVING W NEAR 22 KT. VISIBLE SATELLITE IMAGERY INDICATES AN INVERTED-V CLOUD SIGNATURE NEAR THE WAVE AXIS. A MAXIMUM IN DEEP LAYER MOISTURE IS ALSO OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY BETWEEN 55W-64W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 9N-15N BETWEEN 54W-60W. ISOLATED MODERATE CONVECTION IS ALSO FURTHER W OVER THE WINDWARD ISLANDS FROM 8N-13N BETWEEN 60W-62W. TROPICAL WAVE IS ALONG 76W/77W S OF 16N MOVING W NEAR 18 KT. THE WAVE LIES IN A VERY BROAD AREA OF DEEP LAYER MOISTURE ACROSS THE SRN HALF OF THE CARIBBEAN BASIN S OF 15N AS OBSERVED IN THE TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS HOWEVER WELL W OF THE WAVE AXIS FROM 7N-14N BETWEEN 79W-86W. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 12N16W 12N23W 7N30W 5N40W 4N52W. BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION...WIDELY SCATTERED MODERATE CONVECTION IS FROM 4N-9N BETWEEN 26W-39W. ...DISCUSSION... GULF OF MEXICO... HIGH PRESSURE RIDGING DOMINATES THE ENTIRE GULF OF MEXICO PRODUCING FAIR WEATHER. A FEW CELLS OF SCATTERED MODERATE CONVECTION ARE NOTED ALONG THE COAST OF THE YUCATAN PENINSULA WITHIN 15 NM OF 21.5N89W. 5-10 KT SE RETURN FLOW IS OVER THE E GULF...WHILE 15-20 KT SE FLOW IS OVER THE W GULF W OF 90W. IN THE UPPER LEVELS...A LARGE UPPER LEVEL HIGH IS CENTERED OVER N FLORIDA NEAR 29N83W MOVING E. STRONG SUBSIDENCE COVERS THE ENTIRE GULF. EXPECT...SE RETURN FLOW TO PRODUCE CONVECTION ALONG THE TEXAS AND LOUISIANA COASTS OVER THE NEXT 24 HOURS. CARIBBEAN SEA... A TROPICAL WAVE IS OVER THE CENTRAL CARIBBEAN AND ANOTHER TROPICAL WAVE IS APPROACHING THE WINDWARD ISLANDS. SEE ABOVE. FRESH TO STRONG TRADEWINDS ARE OVER THE CARIBBEAN SEA. VERY ISOLATED CONVECTION IS OVER THE N CARIBBEAN BETWEEN PUERTO RICO AND BELIZE BETWEEN 17N-20N. IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS OVER THE CENTRAL CARIBBEAN NEAR 15N73W. EXPECT...MORE CONVECTION OVER THE W CARIBBEAN W OF 77W...AND OVER THE E CARIBBEAN E OF 67W OVER THE NEXT 24 HOURS AS THE TROPICAL WAVES MOVES W. ATLANTIC OCEAN... A DISSIPATING COLD FRONT IS OVER THE W ATLANTIC ALONG 32N60W 30N70W 29N78W. A 1020 MB HIGH IS E OF THE N BAHAMAS NEAR 26N74W. THE REMNANTS OF HENRI IS N OF THE LEEWARD ISLANDS. SEE ABOVE. A 1022 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 25N44W. A SURFACE TROUGH IS FURTHER E ALONG 32N36W 26N37W. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE TROUGH AXIS. ANOTHER 1022 MB HIGH IS OVER THE E ATLANTIC NEAR 32N29W. IN THE UPPER LEVELS...A RIDGE IS OVER THE W ATLANTIC W OF 60W. AN UPPER LEVEL LOW IS CENTERED NEAR 27N39W. ANOTHER UPPER LEVEL LOW IS CENTERED NEAR 26N26W. AN UPPER LEVEL HIGH IS OVER THE TROPICS NEAR 14N50W. $$ FORMOSA