000 AXNT20 KNHC 191156 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN AUG 19 2012 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...SPECIAL FEATURES... HURRICANE GORDON IS LOCATED NEAR 35.1N 30.7W AT 19/1200 OR ABOUT 340 MI...550 KM WSW OF SAO MIGUEL ISLAND AZORES MOVING E AT 20 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 973 MB. MAXIMUM SUSTAINED WIND SPEED IS 85 KT WITH GUSTS TO 105 KT. FIRST SATELLITE VISIBLE PICTURES OF THE DAY REVEALED A SOMEWHAT LESS DEFINED EYE. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 33N-37N BETWEEN 28W-35W. GORDON IS EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF 3 TO 6 INCHES OVER THE AZORES. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT3/WTNT33 AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. AN ACTIVE TROPICAL WAVE IS LOCATED IN THE ERN/CENTRAL TROPICAL ATLC ALONG 34W...WITH AN ASSOCIATED 1009 MB LOW NEAR 14N35W EMBEDDED WITHIN THE MONSOONAL GYRE. THIS SYSTEM IS MOVING WESTWARD AROUND 20 KT. SCATTERED SHOWERS AND THUNDERSTORMS ARE FROM 10N-18N BETWEEN 31W-38W...WITHIN THE BROAD CONVECTIVE REGION ASSOCIATED TO THE MONSOON TROUGH. ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR A TROPICAL DEPRESSION TO FORM DURING THE NEXT DAY OR TWO...AND THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD AT 20 KT. ...TROPICAL WAVES... TROPICAL WAVE MOVES ACROSS THE CENTRAL TROPICAL ATLC WITH AXIS EXTENDING FROM 17N44W TO A WEAK 1011 MB LOW NEAR 10N45W MOVING W AT 15-20 KT. THE WAVE REMAINS EMBEDDED WITHIN A BROAD AREA OF ENHANCED DEEP LAYER MOISTURE AS NOTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. CONVECTION AROUND THE WAVE AXIS IS LIMITED DUE TO A LARGE DRY AIRMASS ASSOCIATED WITH THE SAHARAN AIR LAYER. ANY SHOWER ACTIVITY IS LIKELY ASSOCIATED TO THE BROAD MONSOONAL GYRE DISCUSSED BELOW. TROPICAL WAVE MOVES ACROSS THE CENTRAL CARIBBEAN WITH AXIS EXTENDING FROM ERN CUBA NEAR 20N76W TO BARANOA IN NRN COLOMBIA NEAR 11N74W MOVING W AT 15-20 KT. THE CIRCULATION AROUND THE AXIS HAS BROADENED COMPARED TO YESTERDAY...AND THE OVERALL CONVECTIVE ACTIVITY HAS DECREASED ACCORDINGLY. ONLY A CLUSTER OF SCATTERED SHOWERS AND THUNDERSTORMS IS NOTED OVER THE NRN EXTENSION OF THE WAVE AXIS MOVING ACROSS THE SRN COASTAL WATERS OF HAITI AND THE WINDWARD PASSAGE N OF 16N BETWEEN 71W-76W... WHERE LOW LEVEL CONVERGENCE IS MAXIMIZED COINCIDING WITH A WEAK UPPER LEVEL LOW PROVIDING FURTHER LIFTING. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST OF GUINEA BISSAU NEAR 11N16W TO 15N24W. THEN...THE MONSOON TROUGH REDEVELOPS W OF THE SPECIAL FEATURE 1009 LOW PRESSURE SYSTEM NEAR 15N30W ALONG 10N40W TO A WEAKER 1011 MB LOW NEAR 10N45W TO 9N50W. THE ITCZ AXIS BEGINS FORM THIS POINT TO THE COAST OF GUYANA NEAR 6N58W. A BROAD AREA CONTAINING CLUSTERS OF SCATTERED MODERATE CONVECTION COVERS FROM 4N-16N BETWEEN 30W-50W. SIMILAR CONVECTION IS WITHIN 120 NM N OF THE ITCZ AND FROM 8N-16N E OF 22W. ...DISCUSSION... GULF OF MEXICO... THE BASE OF A BROAD UPPER LEVEL TROUGH...MOVING ACROSS THE CENTRAL AND ERN CONUS...SWINGS ACROSS THE NRN GULF OF MEXICO PUSHING MULTIPLE SHORTWAVES ABOUT EVERY 6 HOURS. THIS IS BRINGING SCATTERED SHOWERS AND THUNDERSTORMS OVER THE AREA N OF 27N. WHILE THE UPPER LEVEL TROUGH CONTINUES TO SLOWLY MOVE ENE...THE FLOW AROUND THIS FEATURE WILL CONTINUE TO BRING SEVERAL MORE WAVES OF ENERGY OVER THE NEXT 24 HOURS OVER THE NRN AND NE BASIN. THUS EXPECT MORE SCATTERED CONVECTION IN THESE REGIONS DURING THE FORECAST PERIOD. THE BROAD CYCLONIC WIND FIELD RELATED TO FORMER TROPICAL STORM HELENE CONTINUES TO GENERATE SCATTERED SHOWERS AND THUNDERSTORMS OVER THE WRN BAY OF CAMPECHE AND COASTAL WATERS OF TAMPICO S OF 25N W OF 92W. WINDS WILL REMAIN GENTLE TO MODERATE IN THIS REGION DURING THE NEXT 24 HOURS. LIGHT TO GENTLE SE SURFACE FLOW IS ACROSS THE REMAINDER OF THE GULF UNDER STABLE CONDITIONS. CARIBBEAN SEA... INFRA-RED SATELLITE IMAGERY SHOWS A MID LEVEL MESO-CYCLONE OVER THE SW CARIBBEAN CENTERED NEAR 12N82W. THIS COORDINATE DOES NOT REPRESENT A SURFACE CIRCULATION AND IT IS NOT ANALYZED ON THE 0600 UTC SURFACE MAP...BUT RATHER IT IS A CENTER POSITION FOR THE MID LEVEL FEATURE. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 160 NM FROM THE CENTER AT ALL QUADRANTS. TO THE E OF THIS FEATURE...A TROPICAL WAVE IS ANALYZED FROM ERN CUBA TO THE COAST OF COLOMBIA NEAR BARANOA. THE CIRCULATION AROUND THE AXIS HAS BROADENED AND THE OVERALL CONVECTIVE ACTIVITY HAS DECREASED ACCORDINGLY. ONLY A CLUSTER OF SCATTERED SHOWERS AND THUNDERSTORMS IS NOTED OVER THE WINDWARD PASSAGE AND SRN COASTAL WATERS OF HAITI...WHERE LOW LEVEL CONVERGENCE IS MAXIMIZED COINCIDING WITH A WEAK UPPER LEVEL LOW PROVIDING FURTHER LIFTING. SOME LOW-LEVEL MOISTURE IS NOW ENTERING THE FAR SE BASIN S OF 14N E OF 64W INCLUDING THE ISLAND OF TRINIDAD AND TOBAGO. THIS AREA OF SHOWERS WILL CONTINUE TO SPREAD WEST ACROSS THE ERN CARIBBEAN TODAY. THE REMAINDER OF THE CARIBBEAN IS DOMINATED BY DRY AIR AND SUBSIDENCE ALOFT NOTED ON WATER VAPOR IMAGERY. ATLANTIC OCEAN... WATER VAPOR CONTINUES TO SHOW A BROAD LONGWAVE UPPER TROUGH SLOWLY MOVING OFF THE ERN CONUS SEABOARD GENERATING WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE WRN ATLC DISCUSSION AREA N OF 25N BETWEEN 64W-78W. AN UPPER LEVEL LOW IS TO THE E OF THIS CONVECTIVE AREA IS CENTERED NEAR 25N57W WITHOUT ANY SIGNIFICANT IMPACTS. OTHERWISE...BROAD SURFACE RIDGING DOMINATES THE REMAINDER OF THE CENTRAL AND EASTERN ATLC... GUARDED BY A 1021 MB HIGH CENTERED NEAR 27N57W...AND A 1018 MB HIGH AROUND 35N21W. THE FAIR WEATHER PRODUCED BY THESE SURFACE FEATURES IS FURTHER ENHANCED ALOFT BY THE SAHARAN AIR LAYER AND ASSOCIATED DUST ACROSS MOST OF THE DISCUSSION AREA E OF 65W. THE HIGHEST CONCENTRATION OF SAHARAN DUST IS NOTED OVER THE FAR ERN ATLC N OF 17N E OF 34W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA