000 AXNT20 KNHC 230000 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU OCT 22 2015 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 16N16W TO 11N30W TO A 1010 MB LOW NEAR 10N45W. SCATTERED MODERATE CONVECTION IS FROM 10N TO 16N BETWEEN 18W AND 33W. SCATTERED MODERATE CONVECTION IS WITHIN 75 NM OF THE LOW PRES NEAR 10N45W. ...DISCUSSION... GULF OF MEXICO... A PERSISTENT UPPER LEVEL ANTICYCLONE REMAINS CENTERED NEAR THE ITHSMUS OF TEHUANTEPEC NEAR 17N98W AND DOMINATES THE FLOW REGIME OVER MOST OF THE GULF OF MEXICO...AND THE WESTERN HALF OF THE CARIBBEAN. DIFFLUENT UPPER LEVEL SOUTHWESTERLY FLOW BETWEEN THE ANTICYCLONE AND AN UPPER CYCLONE OVER THE ROCKIES COMBINED WITH A SURFACE TROUGH THAT EXTENDS FROM NEAR GALVESTON TEXAS TO EXTREME NE MEXICO SUPPORTS A CLUSTERS OF MODERATE/ISOLATED STRONG CONVECTION ALONG THE TEXAS COAST FROM BROWNSVILLE TO CORPUS CHRISTI AND OUT 60 NM OVER THE GULF OF MEXICO. SOUTHEASTERLY SURFACE WINDS OF 20-25 KT WITH SEAS OF 10-11 FT WERE NOTED OVER THE FAR NW GULF AT BUOYS 42002 AND 42020. UPPER LEVEL ANTICYCLONIC FLOW WAS SPREADING HIGH LEVEL MOISTURE ACROSS MOST OF THE GULF W OF 85W WITH GENERALLY FAIR CONDITIONS AT THE SURFACE UNDER A HIGH PRESSURE RIDGE EXTENDING FROM THE SOUTHERN APPALACHIANS INTO THE GULF. LIGHT TO MODERATE NE WINDS PREVAIL OVER MOST OF THE GULF E OF 90W. EXPECT FRESH TO STRONG SE WINDS AND ADDITIONAL CONVECTION AND HEAVY RAINFALL OVER THE NE GULF OVER THE NEXT 24 HOURS. CARIBBEAN SEA... THE UPPER-LEVEL HIGH THAT DOMINATES THE GULF OF MEXICO ALSO EXTENDS SE COVERING THE CARIBBEAN W OF 75W. TO THE E...AN UPPER- LEVEL LOW IS CENTERED NEAR 16N66W AND A WEAK UPPER LEVEL TROUGH EXTENDING FROM HISPANIOLA TO 14N73W DOMINATES THE EASTERN HALF OF THE BASIN. A SURFACE TROUGH IS OVER THE NW CARIBBEAN EXTENDING FROM 21N83W TO 19N86W. SCATTERED LOW TOPPED SHOWERS AND ISOLATED THUNDERSTORMS WERE NOTED WITHIN 90 NM EITHER SIDE OF THE TROUGH AXIS. THE TAIL END OF A STATIONARY FRONT IS OVER THE WESTERN TIP OF CUBA. ISOLATED THUNDERSTORMS ARE OVER THE WINDWARD PASSAGE ASSOCIATED WITH THE FRONTAL BOUNDARY. THE EASTERN END OF THE E PACIFIC MONSOON TROUGH IS OVER THE SW CARIBBEAN SUPPORTING ISOLATED MODERATE CONVECTION FROM PANAMA AND COSTA RICA TO 12N AND WEST OF 80W. ANOTHER SURFACE TROUGH IS OVER THE EASTERN CARIBBEAN WITH AN AXIS EXTENDING FROM 15N64W TO 11N65W. SCATTERED SHOWERS ARE WITHIN 75 NM OF THE TROUGH AXIS. MAINLY MODERATE TO FRESH TRADE WINDS COVER THE CARIBBEAN BASIN WITH THE STRONGEST WINDS OVER THE NW CARIBBEAN OF 20N EXTENDING TO THE YUCATAN CHANNEL. OVER THE NEXT 24 HOURS ISOLATED CONVECTION WILL REMAIN POSSIBLE OVER THE SW CARIBBEAN AND OVER THE EASTERN CARIBBEAN ASSOCIATED WITH THE WESTWARD MOVING SURFACE TROUGH. ...HISPANIOLA... THE PRESENCE OF A STATIONARY FRONT N OF THE ISLAND AT THE SURFACE AND AN UPPER LEVEL TROUGH ALOFT IS SUPPORTING EXTENSIVE CLOUDINESS WITH SCATTERED SHOWERS AND THUNDERSTORMS ALONG THE NORTH COAST OF HAITI AND EASTERN DOMINICAN REPUBLIC. EXPECT THE SHOWERS AND THUNDERSTORMS TO CONTINUE TONIGHT INTO FRIDAY WITH GRATER THAN NORMAL COVERAGE GIVEN THE UNSTABLE ENVIRONMENT. AS SUCH LOCALLY HEAVY RAINS ARE POSSIBLE WITH LOCALIZED FLOODING TONIGHT AND EARLY FRIDAY. ATLANTIC OCEAN... A SHARP PERSISTENT UPPER LEVEL TROUGH OVER THE W ATLC EXTENDING FROM 31N72W TO HISPANIOLA CONTINUES TO SUPPORT A STATIONARY FRONT THAT EXTENDS INTO THE DISCUSSION AREAS NEAR 31N57W TO A 1011 MB LOW NEAR 29N61W TO A 1010 MB LOW NEAR 26N65W TO NEAR THE WINDWARD PASSAGE/EXTREME EASTERN CUBA. SCATTERED MODERATE CONVECTION IS WITHIN 120-180 NM EITHER SIDE OF THE STATIONARY FRONT. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE ELSEWHERE WITHIN 300 NM OF THE FRONT N OF 27N. FARTHER EAST...A 1008 MB SURFACE LOW IS CENTERED NEAR 27N25W WITH A SURFACE TROUGH THAT EXTENDS FROM THE LOW CENTER TO NEAR 22N25W. ANOTHER TROUGH EXTENDED FROM 32N18W TO 28N23W. THE LOW WAS DROPPING SOUTH AT 15 KT. SCATTERED MODERATE CONVECTION WAS DEVELOPING WELL E OF THE LOW FROM 25N TO 28N BETWEEN 20W AND 24W. OVER THE NEXT 24 HOURS THE NORTHERNMOST LOW ALONG THE STATIONARY FRONT WILL STRENGTHEN SLIGHTLY WHILE THE SOUTHERN LOW DISSIPATES. CONVECTION WILL CONTINUE TO BE LIKELY NEAR THE LOW AND FRONT THROUGH FRIDAY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ COBB