000 AXNT20 KNHC 190600 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC. ...SPECIAL FEATURES... HURRICANE GORDON IS LOCATED NEAR 34.6N 32.7W AT 19/0600...OR ABOUT 395 MI...635 KM WSW OF THE AZORES...MOVING E AT 19 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 965 MB. MAXIMUM SUSTAINED WIND SPEED IS 90 KT WITH GUSTS TO 110 KT. SATELLITE IMAGERY SHOWS A WELL DEFINED EYE. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 32N-37N BETWEEN 30W-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 32W...WITH AN ASSOCIATED 1008 MB LOW NEAR 14N32W EMBEDDED WITHIN THE MONSOONAL GYRE. THIS SYSTEM IS MOVING WESTWARD AROUND 20 KT. SCATTERED SHOWERS AND THUNDERSTORMS ARE FROM 10N-18N BETWEEN 30W-37W...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 ABOUT 17 KT. GLOBAL MODELS HAS A WWD TRAJECTORY TOWARDS THE CARIBBEAN. INTERESTS ACROSS THE E AND NE CARIBBEAN SHOULD MONITOR THE PROGRESS OF THIS SYSTEM. ...TROPICAL WAVES... TROPICAL WAVE MOVES ACROSS THE CENTRAL TROPICAL ATLC WITH AXIS EXTENDING FROM 18N43W TO A WEAK 1010 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 THE ERN TIP OF CUBA NEAR 20N74W TO BARANOA IN NRN COLOMBIA NEAR 10N75W 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 HAITI AND THE WINDWARD PASSAGE N OF 18N...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 12N17W ALONG 16N25W TO THE SPECIAL FEATURE 1008 LOW PRESSURE SYSTEM NEAR 14N32W TO A WEAKER 1010 MB LOW NEAR 10N45W TO 7N49W. THE ITCZ AXIS BEGINS FORM THIS POINT TO THE COAST OF FRENCH GUIANA NEAR 5N53W. A BROAD AREA CONTAINING CLUSTERS OF SCATTERED MODERATE CONVECTION COVERS FROM 6N-16N BETWEEN 30W-50W...AND FROM 6N-19N E OF 25W. ...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 25N E OF 95W. 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 93W. 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 12N81W. THIS COORDINATE DOES NOT REPRESENT A SURFACE CIRCULATION...BUT RATHER 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 THE ERN TIP OF CUBA TO THE COAST OF COLOMBIA NEAR BARANOA. 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 WINDWARD PASSAGE...WHERE LOW LEVEL CONVERGENCE IS MAXIMIZED COINCIDING WITH A WEAK UPPER LEVEL LOW PROVIDING FURTHER LIFTING. 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 63W-80W. AN UPPER LEVEL LOW IS TO THE E OF THIS CONVECTIVE AREA CENTERED NEAR 24N65W 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 1019 MB HIGH AROUND 34N25W. 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