000 AXNT20 KNHC 181758 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST FRI NOV 18 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 1545 UTC. ...TROPICAL WAVES... A TROPICAL WAVE EXTENDS FROM 19N51W TO 10N54W MOVING WNW AT 5-10 KT. THE WAVE IS EMBEDDED WITHIN A BROAD SURGE OF DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. UPPER LEVEL DIFFLUENCE ALOFT IS OVER THE AREA E OF THE WAVE AXIS. THE CONVECTION ASSOCIATED TO THIS WAVE IS ALSO INTERACTING WITH A SURFACE TROUGH TO ITS N MENTIONED IN THE ATLC DISCUSSION BELOW. ...THE ITCZ/THE MONSOON TROUGH... A SMALL PORTION OF THE MONSOON TROUGH CURVES THROUGH WESTERN SENEGAL NEAR 12N16W TO 10N18W WITHOUT CONVECTION. THE ITCZ CONTINUES FROM 10N18W TO 5N23W THEN WESTWARD ALONG 5N34W TO 7N45W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 100 NM ON EITHER SIDE OF THE ITCZ W OF 20W. THE FAR WESTERN PORTION OF THE ITCZ IS ALSO INTERACTING WITH THE UPPER LEVEL CYCLONIC CIRCULATION AND ASSOCIATED DIFFLUENCE MENTIONED ON THE ATLC DISCUSSION BELOW. ...DISCUSSION... GULF OF MEXICO... A WEAKENING STATIONARY FRONT EXTENDS SW ACROSS THE FLORIDA STRAITS INTO THE YUCATAN PENINSULA ALONG 25N80W TO 22N88W WITH VERY LIMITED CONVECTION...AS WATER VAPOR IMAGERY SHOWS VERY DRY AIR ALOFT AND STRONG SUBSIDENCE SUPPRESSING DEEP CONVECTION ACROSS THE DISCUSSION AREA. THIS FRONT IS EXPECTED TO DISSIPATE BEFORE REACHING THE NW CARIBBEAN. HOWEVER...SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE OVER THE FAR SW BASIN INTO THE BAY OF CAMPECHE S OF 21N W OF 93W. THE REMAINDER OF THE GULF IS COVERED BY LOW LEVEL STRATOCUMULUS CLOUDS MOVING ALONG WITH THE MODERATE TO FRESH ANTICYCLONIC FLOW. THIS FLOW INCREASES UP TO NEAR 30 KT OVER THE FAR ERN GULF...WITHIN 120 NM OFF THE WRN COAST OF THE FLORIDA PENINSULA. NO SIGNIFICANT CHANGES ARE OBSERVED ON SHORT RANGE COMPUTER MODELS. CARIBBEAN SEA... SCATTERED SHOWERS AND THUNDERSTORMS ARE OVER THE SW CARIBBEAN S OF 13N W OF 74W...ASSOCIATED TO THE MONSOON TROUGH ANALYZED ACROSS COSTA RICA INTO NRN COLOMBIA. THIS AREA OF CONVECTION IS EXPECTED TO LINGER OVER THE NEXT 24 HOURS. ELSEWHERE ACROSS THE BASIN...MOSTLY FAIR WEATHER IS OBSERVED ACROSS THE AREA ON VISIBLE SATELLITE IMAGERY WITH LOW-TOP ISOLATED SHOWERS DOTTING THE BASIN MOVING ALONG WITH THE FRESH TRADE WIND FLOW. NO SIGNIFICANT CHANGES ARE EXPECTED DURING THE NEXT 24 HOURS. ATLANTIC OCEAN... A BROAD UPPER LEVEL TROUGH MOVES ACROSS THE WRN NORTH ATLC SUPPORTING A COLD FRONT THAT ENTERS THE DISCUSSION AREA ALONG 32N66W TO ACROSS THE NRN BAHAMAS NEAR 26N77W INTO THE STRAITS OF FLORIDA ALONG 25N80W. SCATTERED SHOWERS ARE WITHIN 40 NM ON EITHER SIDE OF THE FRONT N OF 28N AND WITHIN 30 NM N OF THE BOUNDARY W OF 71W. FARTHER EAST...THE INTERACTION BETWEEN A SURFACE TROUGH ANALYZED FROM 29N52W TO 22N56W AND A TROPICAL WAVE TO THE S OF THE TROUGH...ANALYZED FROM 19N51W TO 10N54W... IS GENERATING A N-S ELONGATED AREA OF SCATTERED SHOWERS AND THUNDERSTORMS FROM 10N-30N BETWEEN 43W-51W. THE ACTIVITY IS FURTHER ENHANCED BY AN ELONGATED UPPER LOW PRODUCING STRONG DIFFLUENCE OVER THE CONVECTION REGION. SHORT RANGE COMPUTER MODELS SUGGEST THIS AREA OF CONVECTION WILL REMAIN NEARLY STATIONARY DURING THE NEXT 24 HOURS. THE REMAINDER OF THE ATLC E OF 43W IS UNDER FAIR WEATHER SUPPORTED BY A STRONG SURFACE RIDGE ANCHORED BY A 1028 MB HIGH NEAR 33N37W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA