000 AXNT20 KNHC 231745 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT MON JUL 23 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1735 UTC. ...TROPICAL WAVES... MODEL GUIDANCE AND SURFACE OBSERVATIONS CONFIRMED A TROPICAL WAVE LOCATED E OF THE LESSER ANTILLES EARLIER THIS MORNING. THE WAVE WAS ADDED TO THE 1200 UTC SURFACE MAP WITH AXIS FROM 18N55W TO 12N56W. WAVE IS EMBEDDED IN A LOW AMPLITUDE SURGE OF DEEP MOISTURE NOTED ON TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE TO HEAVY SHOWERS AND THUNDERSTORMS ARE S OF 13N BETWEEN 57W-66W INCLUDING THE LESSER ANTILLES ISLANDS S OF SAINT LUCIA. TROPICAL WAVE MOVES INTO THE CENTRAL TROPICAL ATLC WITH AXIS ANALYZED FROM 21N31W TO THE MONSOON TROUGH AXIS NEAR 13N35W MOVING W AT ABOUT 10 KT. WAVE REMAINS ALONG THE LEADING EDGE OF A SURGE OF DEEP LAYER MOISTURE AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY. HOWEVER...ANY DEEP CONVECTION IS CURRENTLY ASSOCIATED TO THE MONSOON TROUGH. TROPICAL WAVE MOVES ACROSS THE CENTRAL CARIBBEAN WITH AXIS EXTENDING FROM 18N72W TO 12N71W MOVING W NEAR 20 KT. WAVE SIGNATURE HAS BECOME LESS DISTINCTIVE ON TOTAL PRECIPITABLE WATER IMAGERY AS THE WAVE MOVES WITHIN A REGION OF SAHARAN DUST ...STRONG SUBSIDENCE AND DRY AIR. THEREFORE...NO ASSOCIATED CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA-BISSAU IN WEST AFRICA NEAR 12N16W TO ACROSS THE TROPICAL ATLC ALONG 14N22W 12N31W 9N42W...WHERE THE ITCZ CONTINUES ALONG 11N530W TO INLAND OVER VENEZUELA NEAR 9N61W. CLUSTERS OF SCATTERED WEAK CONVECTION ARE WITHIN 120 NM ON EITHER SIDE OF THE MONSOON TROUGH AND ITCZ W OF 20W. CLUSTERS OF SCATTERED MODERATE TO STRONG CONVECTION ARE MOVING OUT WEST AFRICA COAST FROM 5N-13N E OF 20W. ...DISCUSSION... GULF OF MEXICO... A MID LEVEL CYCLONIC CIRCULATION IS NOTED OVER THE NE GULF... BEST DEPICTED AT 700 MB LEVEL. THIS FEATURE SUPPORTS A SURFACE TROUGH ANALYZED FROM THE NRN FLORIDA PENINSULA NEAR 30N83W TO 28N86W GENERATING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS N OF 26N E OF 86W. TO THE WEST OF THIS AREA OF CONVECTION...AN INVERTED UPPER TROUGH MOVES ACROSS THE CENTRAL AND WRN GULF PROVIDING ENOUGH LIFTING TO PRODUCE SIMILAR CONVECTION N OF 23N W OF 89W. FAIR WEATHER IS ELSEWHERE ACROSS THE AREA WITH A FEW ISOLATED SHOWERS OVER THE BAY OF CAMPECHE. COMPUTER MODELS SUGGEST THE OVERALL ACTIVITY WILL DECREASE OVER THE NEXT 24 HOURS...WHILE THE ACTIVITY OVER THE BAY OF CAMPECHE INCREASES DURING THE FORECAST PERIOD. CARIBBEAN SEA... THE ATTENTION HAS TURNED TO THE FAR SE CARIBBEAN AND LESSER ANTILLES ISLANDS S OF SAINT LUCIA...AS A RECENTLY ADDED TROPICAL WAVE MOVES OVER THESE GROUP OF ISLANDS TODAY. SCATTERED MODERATE TO HEAVY SHOWERS AND THUNDERSTORMS ARE S OF 13N E OF 66. THIS AREA OF CONVECTION WILL CONTINUE TO TRACK W ALONG THE WAVE AXIS DURING THE NEXT 24 HOURS. SIMILAR RAINFALL ACTIVITY IS OVER THE FAR WRN CARIBBEAN AND CENTRAL AMERICA COUNTRIES S OF 19N W OF 81W...ASSOCIATED TO LOW LEVEL MOISTURE CONVERGENCE EMBEDDED IN THE EASTERLY TRADE WINDS. A WEAK TROPICAL WAVE MOVES ACROSS THE CENTRAL CARIBBEAN WITHOUT ANY IMPACTS. THE REMAINDER OF THE DISCUSSION AREA IS UNDER FAIR WEATHER CONDITIONS PROVIDED BY STRONG SUBSIDENCE AND SAHARAN DUST ALOFT ACROSS THE AREA. THE ATLC SURFACE RIDGE WILL MAINTAIN FRESH TO STRONG TRADE WINDS ACROSS MOST OF THE CARIBBEAN THROUGH THE END OF THE WORK WEEK. ATLANTIC OCEAN... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OVER THE FAR WRN ATLC N OF 25N W OF 75W ASSOCIATED TO A BROAD MID LEVEL CYCLONIC CIRCULATION CENTERED OVER THE NE GULF. THIS CLUSTER OF SHOWERS WILL MOVE NNE DURING THE NEXT 24 HOURS...AROUND THE WRN PERIPHERY OF A NEARLY STATIONARY SURFACE RIDGE OF HIGH PRESSURE ANCHORED AS A 1025 MB HIGH NEAR 28N69W. OTHERWISE...BROAD UPPER LEVEL RIDGING COVERS THE REMAINDER OF THE ATLC DISCUSSION AREA SUPPORTING A 1026 MB HIGH NEAR 32N33W AND A 1025 MB HIGH S OF THE AZORES NEAR 36N24W. SATELLITE IMAGERY CONTINUES TO SHOW SAHARAN DUST COVERING MOST OF THE ATLC BASIN REACHING TO THE BAHAMAS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA