000 AXNT20 KNHC 280000 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI SEP 27 2013 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 2315 UTC. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE JUST OFF THE COAST OF WEST AFRICA EXTENDS FROM 18N18W TO 6N18W MOVING W AT 10-15 KT. A DISTINCT MOIST AREA IS DEPICTED ON THE SSMI TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 6N-16N BETWEEN 13W-26W. AN ATLANTIC OCEAN TROPICAL EXTENDS FROM21N51W TO 10N51W WAVE IS ALONG 19N49W 14N48W 10N47W MOVING W AT 10-15 KT. THIS WAVE IS ALSO OVER AN UPPER LEVEL DIFFLUENT AREA THAT IS ENHANCING CONVECTION. CLUSTERS OF SCATTERED MODERATE TO STRONG CONVECTION IS FROM 15N-25N BETWEEN 46W-51W. A CARIBBEAN TROPICAL WAVE EXTENDS FROM 16N60W TO 10N59W MOVING W AT 10-15 KT. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE WAVE AXIS. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH THE COASTAL AREAS OF GUINEA- BISSAU AT 12N16W TO 8N22W. THE ITCZ CONTINUES FROM 8N22W TO 7N34W TO 4N44W. BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION...SCATTERED MODERATE CONVECTION IS FROM 6N-9N BETWEEN 33W-47W. ...DISCUSSION... THE GULF OF MEXICO... AS OF 2100 UTC...A COLD FRONT EXTENDS FROM THE STRAITS OF FLORIDA AT 23N80W TO THE CENTRAL GULF OF MEXICO AT 24N88W. A DISSIPATING STATIONARY FRONT CONTINUES TO 25N92W. ISOLATED MODERATE CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE FRONTS. THE BASE OF A SURFACE RIDGE IS OVER THE NE GULF AND N FLORIDA. RADAR IMAGERY SHOWS LIGHT SHOWERS ARE OVER CENTRAL FLORIDA BETWEEN ORLANDO AND COCOA BEACH. MOST OF THE REMAINDER OF THE GULF HAS FAIR WEATHER. IN THE UPPER LEVELS...AN UPPER LEVEL RIDGE IS OVER THE W GULF W OF 90W. THE BASE OF AN UPPER LEVEL TROUGH IS OVER THE E GULF. STRONG SUBSIDENCE COVERS THE ENTIRE GULF. EXPECT OVER THE NEXT 24 HOURS FOR THE FRONT TO MOVE OVER CUBA AND WEAKEN. THE CARIBBEAN SEA... A TROPICAL WAVE IS OVER THE E CARIBBEAN. SEE ABOVE. 10-20 KT TRADEWINDS ARE OVER THE CARIBBEAN SEA WITH STRONGEST WINDS OVER THE CENTRAL CARIBBEAN. AFTERNOON AND EVENING AIRMASS THUNDERSTORMS ARE NOW OVER CUBA...HISPANIOLA...AND JAMAICA. ISOLATED MODERATE CONVECTION IS INLAND OVER CENTRAL AMERICA FROM FROM COSTA RICA TO THE YUCATAN PENINSULA WITH STRONGEST CONVECTION OVER NICARAGUA. A MONSOON TROUGH EXTENDS FROM N COLOMBIA AT 8N75W TO BEYOND COSTA RICA AT 10N85W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 6N-10N BETWEEN 75W-84W. IN THE UPPER LEVELS...A SMALL UPPER LEVEL LOW IS CENTERED S OF THE CAYMAN ISLANDS NEAR 18N81W. UPPER LEVEL DIFFLUENCE S OF THE CENTER IS PRODUCING ISOLATED MODERATE CONVECTION OVER THE CENTRAL CARIBBEAN FROM 12N-17N BETWEEN 75W-80W. EXPECT CONTINUED CONVECTION OVER THE SW CARIBBEAN OVER THE NEXT 24 HOURS. HISPANIOLA... AFTERNOON AND EVENING AIRMASS THUNDERSTORMS ARE NOW OVER HISPANIOLA...MOSTLY OVER HAITI. UPPER LEVEL MOISTURE IS NOTED OVER HAITI WHILE STRONG SUBSIDENCE REMAINS OVER THE DOMINICAN REPUBLIC. EXPECT SIMILAR AFTERNOON AND EVENING AIRMASS THUNDERSTORMS TO DEVELOP TOMORROW. THE ATLANTIC OCEAN... A 1007 MB LOW IS CENTERED OVER THE W ATLANTIC NEAR 29N72W. A COLD FRONT EXTENDS SW TO THE CENTRAL BAHAMAS AND THE STRAITS OF FLORIDA ALONG 26N72W 24N75W 23N80W. A WARM FRONT EXTENDS E OF THE LOW TO 30N70W. A STATIONARY FRONT CONTINUES FURTHER E TO 28N65W WHILE A COLD FRONT CONTINUES FURTHER E TO 31N60W. ISOLATED MODERATE CONVECTION IS FROM 25N-31N BETWEEN 60W-71W. SIMILAR CONVECTION IS WITHIN 60 NM OF THE REMAINDER OF THE FRONTS. A 1020 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 24N38W. OF NOTE IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 24N56W. UPPER LEVEL DIFFLUENCE E OF THE CENTER IS ENHANCING THE SCATTERED MODERATE TO STRONG CONVECTION FROM 15N-25N BETWEEN 46W-51W. EXPECT OVER THE NEXT 24 HOURS FOR THE LOW AND FRONTAL SYSTEM OVER THE W ATLANTIC TO MOVE E WITH CONTINUED CONVECTION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA