000 AXNT20 KNHC 241723 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT OCT 24 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... LOW PRESSURE IS EXPECTED TO DEVELOP TONIGHT OVER SE TX AND TRACK ACROSS THE NW GULF SUNDAY AND TO THE LOUISIANA COAST SUNDAY NIGHT. STRONG NW WINDS ARE EXPECTED TO BUILD TO MINIMAL GALE FORCE FROM 24N TO 29N W OF 94W BEHIND THE COLD FRONT ASSOCIATED WITH THE LOW AS THE LOW TRACKS OVER THE NW GULF ON SUNDAY. SEAS OF 8 TO 12 FEET WILL BE POSSIBLE. THE WINDS ARE EXPECTED TO DIMINISH BELOW GALE FORCE THROUGH MONDAY AS THE LOW TRACKS NE OVER INLAND LOUISIANA...AND THE COLD FRONT MOVES SE OF THE AREA. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND THE OFFSHORE FORECAST...MIAOFFNT4/ FZNT24 KNHC...FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA OVER THE E TROPICAL ATLC NEAR 09N13W TO 04N22W...WHERE THE ITCZ BEGINS AND CONTINUES TO 04N32W. ISOLATED MODERATE CONVECTION IS FROM 02N TO 07N BETWEEN 11W AND 23W. ...DISCUSSION... GULF OF MEXICO... A PERSISTENT UPPER RIDGE REMAINS CENTERED OVER THE GULF ANCHORED ALONG THE COAST OF MEXICO NEAR VERACRUZ WITH A RIDGE AXIS EXTENDING NE TO OVER THE E CONUS. MEANWHILE...AN UPPER TROUGH IS OVER THE S ROCKIES. SOUTHWESTERLY FLOW ALOFT BETWEEN THESE FEATURES IS ADVECTING DEEP MOISTURE OVER THE W GULF. A COLD FRONT IS OVER TX MOVING SE TOWARD THE NW GULF COAST. THE COMBINATION OF LOW LEVEL RETURN FLOW AND SW MOIST FLOW ALOFT SUPPORTS WIDESPREAD SHOWERS AND ISOLATED MODERATE CONVECTION NW OF A LINE FROM 24N98W TO 29N90W. E TO SE MODERATE TO FRESH WINDS COVER THE MAJORITY OF THE GULF THIS AFTERNOON AROUND HIGH PRESSURE CENTERED OVER NEW ENGLAND. OVER THE NEXT 24 HOURS A LOW PRESSURE AREA IS EXPECTED TO DEVELOP OVER THE NW GULF AS THE COLD FRONT MOVES SE OVER THE GULF WATERS FROM TX. GALE FORCE WINDS WILL BE POSSIBLE BEHIND THE FRONT OVER THE NW GULF STARTING SUNDAY. PLEASE REFER TO THE SPECIAL FEATURES SECTION FOR MORE DETAILS. CONVECTION WILL REMAIN LIKELY ACROSS THE NW GULF THROUGH TONIGHT...SPREADING SE WITH THE COLD FRONT INTO THE CENTRAL GULF SUNDAY NIGHT. CARIBBEAN SEA... UPPER LEVEL NORTHERLY FLOW DOMINATES THE WESTERN CARIBBEAN AROUND AN UPPER LEVEL ANTICYCLONE OVER THE SW GULF OF MEXICO AND VERACRUZ. AN UPPER TROUGH OVER THE W ATLC SUPPORTS WESTERLY FLOW ALOFT OVER THE REMAINDER OF THE CARIBBEAN. DRY AIR AND SUBSIDENCE IS INHIBITING CONVECTION OVER THE N CENTRAL AND NW CARIBBEAN. THE E PACIFIC MONSOON TROUGH EXTENDS OVER THE SW CARIBBEAN TO A STATIONARY 1008 MB LOW NEAR 10N77W. SCATTERED MODERATE CONVECTION IS S OF 13N BETWEEN 75W AND 85W. UPPER LEVEL ASCENT OVER THE EASTERN CARIBBEAN DUE TO THE W ATLC UPPER TROUGH SUPPORTS SCATTERED THUNDERSTORMS FROM 13N TO 20N BETWEEN 61W AND 71W...INCLUDING THE LEEWARD ISLANDS AND PUERTO RICO. MODERATE TO FRESH TRADE WINDS COVER THE CENTRAL AND WESTERN CARIBBEAN. TRADE WIND FLOW IS DISRUPTED SOMEWHAT OVER THE EASTERN CARIBBEAN DUE TO A SURFACE TROUGH EXTENDING N FROM PUERTO RICO...WITH GENERALLY SE WINDS AROUND 10 KT OVER THE EASTERN CARIBBEAN. ...HISPANIOLA... AN UPPER TROUGH EXTENDS FROM THE W ATLC OVER HISPANIOLA AND THE E CARIBBEAN. FAVORABLE ASCENT ASSOCIATED WITH THE TROUGH HAS SHIFTED EAST OF THE ISLAND WITH VERY DRY AIR ALOFT NOTED IN WATER VAPOR IMAGERY NOW ACROSS THE REGION. SHALLOW MOISTURE MAY SUPPORT ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING. THE CENTER OF THE UPPER TROUGH TO THE NORTH IS FORECAST TO DRIFT S TOWARD HISPANIOLA EARLY NEXT WEEK WHICH COULD HELP TO ENHANCE SHOWER AND THUNDERSTORM ACTIVITY DURING THAT TIME. ATLANTIC OCEAN... AN UPPER TROUGH OVER THE W ATLC SUPPORTS A COLD FRONT THAT IS BEGINNING TO ENTER OUR AREA OF DISCUSSION ALONG 31N BETWEEN 72W AND 75W. THIS UPPER TROUGH ALSO SUPPORTS A 1008 MB LOW CENTERED NEAR 31N61W WITH A COLD FRONT EXTENDING FROM THE LOW CENTER TO 22N63W...WHERE IT TRANSITIONS TO A SURFACE TROUGH TO 19N66W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 16N TO 25N BETWEEN 52W AND 65W. ISOLATED THUNDERSTORMS ARE FROM 20N TO 28N BETWEEN 65W AND 72W. TWO SURFACE TROUGHS ARE OVER THE TROPICAL N ATLC. THE WESTERNMOST TROUGH EXTENDS FROM 15N49W TO 10N49W. ISOLATED THUNDERSTORMS ARE POSSIBLE WITHIN 100 NM OF THE TROUGH AXIS. THE EASTERNMOST TROUGH EXTENDS FROM 14N 36W TO 09N35W. ISOLATED MODERATE CONVECTION IS WITHIN 90 NM OF THE TROUGH AXIS N OF 11N. A 1014 MB SURFACE LOW IS NEAR 21N24W WITH A SURFACE TROUGH EXTENDING FROM 25N18W THROUGH THE LOW CENTER TO 18N27W. NO DEEP CONVECTION IS NOTED WITH THIS SYSTEM. OVER THE NEXT 24 HOURS CONVECTION WILL CONTINUE NEAR THE COLD FRONT AND SURFACE TROUGH ALONG 60W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO