000 AXNT20 KNHC 311748 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN JUL 31 2011 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... A TROPICAL WAVE IS JUST E OF THE LESSER ANTILLES FROM 22N57W TO 18N59W TO 13N58W. THIS WAVE IS NOW SEPARATED FROM THE 1007 MB LOW CENTERED NEAR 13N52W. THESE TWO FEATURES ARE EMBEDDED WITHIN A BROAD AREA OF DEEP MOISTURE ON TPW PRODUCT. THE CIRCULATION ASSOCIATED TO THE 1007 MB LOW HAS BECOME BETTER ORGANIZED OVER THE PAST 12 HOURS. THUS...THIS SYSTEM IS CLOSE TO BECOMING A TROPICAL DEPRESSION WITH A THREAT TO THE LESSER ANTILLES AND PUERTO RICO. TROPICAL CYCLONE WATCHES OR WARNINGS WOULD LIKELY BE REQUIRED FOR PARTS OF THESE GROUP OF ISLANDS. INTERESTS IN THESE AREAS SHOULD CLOSELY MONITOR THE PROGRESS OF THIS SYSTEM AS IT MOVES WNW AT 15 TO 20 KT. AN AIR FORCE HURRICANE HUNTER AIRCRAFT IS SCHEDULED TO INVESTIGATE THIS DISTURBANCE LATER TODAY. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 12N-19N BETWEEN 57W-60W... AND FROM 12N-16N BETWEEN 48W-54W. ...TROPICAL WAVES... A TROPICAL WAVE IN THE ATLC IS ANALYZED FROM 22N40W TO 12N39W MOVING W AT 15 KT. THIS WAVE IS LOCATED ALONG THE LEADING EDGE OF A WEAK LOW LEVEL MOISTURE SURGE DEPICTED ON TOTAL PRECIPITABLE WATER PRODUCT. WATER VAPOR IMAGERY INDICATES AN UPPER LEVEL INVERTED TROUGH IS IN THE VICINITY OF THE WAVE. NO SIGNIFICANT CONVECTION IS NOTED WITH THE WAVE AT THIS TIME. A TROPICAL WAVE IS MOVING ACROSS CENTRAL AMERICA AND THE YUCATAN PENINSULA FROM 23N87W TO 12N87W MOVING W AT 10-15 KT. THE WAVE IS EMBEDDED WITHIN AN AREA OF DEEP MOISTURE THAT COVERS MOST OF THE NW CARIBBEAN. BROAD LOW LEVEL CLOUD CYCLONIC CURVATURE IS OBSERVED ON SATELLITE DATA. SCATTERED HEAVY SHOWERS AND THUNDERSTORMS ARE AFFECTING THE W AND NW CARIBBEAN WATERS W OF 80W...WITH THE STRONGEST CONVECTION NOTICED WITHIN 120 NM OF THE COASTS OF NE NICARAGUA AND E HONDURAS. A TROPICAL WAVE CURRENTLY OVER WEST AFRICA IS EXPECTED TO ENTER THE EAST ATLC WATERS OVER THE NEXT 24 HOURS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 21N17W TO 11N30W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 11N30W TO 9N40W TO 7N44W TO 13N51W TO THE COAST OF VENEZUELA AT 10N61W. SCATTERED MODERATE CONVECTION IS OFF THE COAST OF WEST AFRICA FROM 6N-11N BETWEEN 19W-25W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 2N-7N BETWEEN 40W-48W. ...DISCUSSION... GULF OF MEXICO... A 1019 MB HIGH IS OVER LOUISIANA NEAR 32N94W PRODUCING FAIR WEATHER OVER THE NW GULF OF MEXICO N OF 23N AND W OF 90W. A WEAK SURFACE TROUGH IS OVER N FLORIDA AND THE NE GULF FROM 31N82W TO 27N86W. ISOLATED MODERATE CONVECTION IS FROM 25N-30N BETWEEN 84W-87W. ELSEWHERE...SCATTERED MODERATE TO STRONG CONVECTION IS OVER THE WESTERN BAY OF CAMPECHE FROM 19N-22N BETWEEN 94W-97W. EXPECT OVER THE NEXT 24 HOURS FOR A TROPICAL WAVE THAT IS PRESENTLY OVER THE YUCATAN PENINSULA TO MOVE W TO THE BAY OF CAMPECHE WITH CONVECTION. ALSO EXPECT CONTINUED CONVECTION OVER THE NE GULF. CARIBBEAN SEA... A TROPICAL WAVE IS OVER CENTRAL AMERICA PRODUCING CONVECTION. SEE ABOVE. THIS AREA OF PRECIPITATION AND MOISTURE IS EXPECTED TO SHIFT WESTWARD OVER THE NEXT 24 HOURS WITH THE POTENTIAL FOR LOCALLY HEAVY RAINFALL AND POSSIBLE FLASH FLOODING ACROSS CENTRAL AMERICA. FURTHER E...ISOLATED MODERATE CONVECTION IS N OF JAMAICA FROM 18N-20N BETWEEN 78W-81W. ELSEWHERE...AN AREA OF SCATTERED MODERATE CONVECTION IS OVER THE SW CARIBBEAN FROM 11N-13N BETWEEN 76W-78W DUE TO THE MONSOON TROUGH. THE SPECIAL FEATURE TROPICAL WAVE AND LOW JUST E OF THE LESSER ANTILLES WARRANTS WATCHING OVER THE NEXT SEVERAL DAYS. ATLANTIC OCEAN... A 1030 MB HIGH IS CENTERED W OF THE AZORES NEAR 38N34W. A RIDGE AXIS EXTENDS SW FROM THE HIGH TO 30N64W PRODUCING FAIR WEATHER. ALONG THE COAST OF W AFRICA THE CIMSS SAHARAN AIR LAYER TRACKING PRODUCT AND VISIBLE METEOSAT-9 SATELLITE IMAGERY SHOW A LARGE AREA OF AFRICAN DUST FROM 16N-30N E OF 38W. ELSEWHERE...THE TROPICAL WAVES ARE THE PREDOMINATE WEATHER PRODUCERS IN THE BASIN. OF INTEREST IN IN THE UPPER LEVELS AN UPPER LEVEL LOW IS CENTERED NEAR 35N56W. SCATTERED SHOWERS ARE W OF THE CENTER FROM 29N-34N BETWEEN 56W-60W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA