000 AXNT20 KNHC 081104 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE SEP 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...SPECIAL FEATURES... TROPICAL STORM FRED IS CENTERED NEAR 11.8N 27.3W AT 08/0900 UTC OR ABOUT 245 NM SW OF THE SOUTHERNMOST CAPE VERDE ISLANDS MOVING W AT 13 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 9N-14N BETWEEN 25W-30W. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 58W S OF 23N MOVING W NEAR 18 KT. CIMSS WAVETRAK MODEL GUIDANCE INDICATES A MAXIMUM OF 850 MB VORTICITY IN THE VICINITY OF THE WAVE AXIS N OF 15N BETWEEN 53W-59W. AS THE WAVE MOVES BENEATH A MODERATELY SUBSIDENT ATMOSPHERE AS NOTED ON WATER VAPOR IMAGERY...ONLY ISOLATED SHOWERS AND TSTMS ARE WITHIN 90 NM EITHER SIDE OF A LINE FROM 20N53W TO 16N62W. TROPICAL WAVE IS ALONG 77W S OF 19N MOVING W NEAR 15 KT. THIS WAVE REMAINS ILL-DEFINED ACROSS THE WRN CARIBBEAN AND MODERATELY DRY AIR IS NOTED ALOFT IN THE UPPER LEVELS. NO DEEP CONVECTION ACCOMPANIES THIS WAVE. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 15N17W 14N23W 8N29W 5N40W 10N57W. BESIDES THE CONVECTION ASSOCIATED WITH TROPICAL STORM FRED AND THE TROPICAL WAVE ALONG 58W...SCATTERED MODERATE CONVECTION IS ALONG THE W AFRICA COAST FROM 8N-19N BETWEEN 12W-18W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 4N-7N BETWEEN 30W-38W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED IN THE BAY OF CAMPECHE NEAR 19N95W AND EXTENDS UPPER RIDGING ACROSS MUCH OF THE GULF IN THE WAY OF WESTERLY ZONAL FLOW. THE LACK OF ANY SIGNIFICANT SURFACE LEVEL FEATURES AND AN OVERALL WEAK PRESSURE GRADIENT IS PROVIDING THE GULF WITH GENERALLY LIGHT WINDS CIRCULATING AROUND A SURFACE RIDGE THAT EXTENDS FROM THE SE CONUS THROUGH 25N90W TO NEAR TUXPAN MEXICO. UPPER LEVEL DIFFLUENCE IN ASSOCIATION WITH THE UPPER LEVEL RIDGE IS GENERATING ENOUGH ATMOSPHERIC LIFT FOR ISOLATED SHOWERS ACROSS THE WRN GULF FROM 23N-28N W OF 88W. SCATTERED SHOWERS ARE TSTMS ARE ALSO OCCURRING OVER THE BAY OF CAMPECHE S OF 21N BETWEEN 91W-99W...INCLUDING PORTIONS OF INTERIOR SRN MEXICO. CARIBBEAN SEA... A TROPICAL WAVE IS ALONG 77W WITH NO SIGNIFICANT CONVECTION ASSOCIATED WITH THE WAVE OVER THE WRN CARIBBEAN. AN UPPER LEVEL TROUGH DIPS SW FROM A SW NORTH ATLC UPPER LOW CENTERED NEAR 25N68W ACROSS HISPANIOLA TO NEAR COASTAL COSTA RICA. NLY UPPER LEVEL WINDS ARE FOUND W OF 80W AND ARE PROVIDING AN OVERALL SUBSIDENT ATMOSPHERE ACROSS THE NW CARIBBEAN AND PORTIONS OF CENTRAL AMERICA. HOWEVER...SCATTERED SHOWERS AND TSTMS CONTINUE S OF CUBA AND ARE LOCATED FROM 18N-22N BETWEEN 77W-82W. MOSTLY DRY AIR ALOFT ON SWLY WINDS ARE ACROSS THE REMAINDER OF THE CARIBBEAN BASIN E OF 80W. AS MODERATE TO FRESH TRADES CONTINUE ACROSS THE BASIN IN THE LOW LEVELS...PASSING ISOLATED SHOWERS ARE N OF 14N E OF 70W. ALSO WITH THE APPROACH OF THE TROPICAL WAVE ALONG 58W...EXPECT SHOWERS TO INCREASE IN COVERAGE ACROSS THE LEEWARD ISLANDS OVER THE NEXT 12-24 HOURS. ATLANTIC OCEAN... A SURFACE TROUGH ENTERS THE DISCUSSION AREA NEAR 32N77W AND EXTENDS SSW TO NEAR WEST PALM BEACH FLORIDA. ISOLATED SHOWERS ARE WITHIN 150 NM TO THE E OF THE SURFACE TROUGH. FARTHER TO THE E...AN UPPER LEVEL LOW IS CENTERED NEAR 25N68W AND IS GENERATING AN AREA OF SCATTERED SHOWERS FROM 20N-30N BETWEEN 63W-74W. INTO THE CENTRAL ATLC...A COLD FRONT DIPS INTO THE DISCUSSION AREA NEAR 32N39W AND EXTENDS SW TO 29N51W. SCATTERED SHOWERS AND POSSIBLE ISOLATED TSTMS ARE WITHIN 90 NM EITHER SIDE OF THE FRONT. TO THE SE OF THE FRONT...A SURFACE TROUGH IS ANALYZED ALONG 25N37W TO 18N38W. A 1012 MB LOW IS EMBEDDED ALONG THE TROUGH NEAR 20N38W. SCATTERED SHOWERS ARE MAINLY N OF THE LOW CENTER FROM 21N-26N BETWEEN 33W-39W. ACROSS THE TROPICAL ERN ATLC...AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED NW OF TROPICAL STORM FRED NEAR 16N33W. $$ HUFFMAN