000 AXNT20 KNHC 170538 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU OCT 17 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 12N39W TO 3N43W MOVING W 20 KT. WAVE IS EMBEDDED WITHIN A BROAD AREA OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. THIS WAVE IS BENEATH AN UPPER RIDGE WITH NO ASSOCIATED DEEP CONVECTION. TROPICAL WAVE EXTENDS FROM 17N47W TO 8N55W MOVING W NEAR 10 KT. WAVE IS EMBEDDED WITHIN A BROAD AREA OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. HOWEVER THERE IS NO ASSOCIATED DEEP CONVECTION. TROPICAL WAVE THAT WAS OVER THE FAR W CARIBBEAN AND CENTRAL AMERICA IS NO LONGER IN THE CARIBBEAN BASIN. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 11N15W AND CONTINUES TO 6N18W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 6N28W TO E OF THE EASTERN MOST TROPICAL WAVE NEAR 7N39W THEN RESUMES W OF THE WAVE NEAR 6N45W TO SOUTH AMERICA NEAR 5N53W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE INLAND AND WITHIN 200 NM ALONG THE COAST OF AFRICA BETWEEN 5N-12N...WITHIN 90/120 NM EITHER SIDE OF THE ITCZ BETWEEN 21W-37W...AND FROM 2N-10N BETWEEN 38W-50W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER TROUGH IS OVER THE CENTRAL PLAIN STATES MOVING OVER THE UPPER MISSISSIPPI VALLEY SUPPORTING A COLD FRONT THAT ENTERS THE NW GULF OVER SW LOUISIANA NEAR 29N92W TO OVER S TEXAS JUST N OF BROWNSVILLE TO NE MEXICO. A BROAD UPPER RIDGE DOMINATES THE GULF WATERS ANCHORED N OF THE YUCATAN PENINSULA NEAR 23N88W. A WEAK SURFACE RIDGE COVERS THE REMAINDER OF THE GULF ANCHORED BY A 1016 MB HIGH OFF THE FLORIDA COAST NEAR 29N86W. THE SOUTHERLY FLOW W OF THE HIGH AND E OF THE FRONT ARE GENERATING ISOLATED SHOWERS N OF 26N W OF 90W. THIS IS LEAVING THE REMAINDER OF THE GULF UNDER MOSTLY CLEAR SKIES TONIGHT. COLD FRONT WILL MOVE SE AND EXTEND FROM MISSISSIPPI TO NE MEXICO LATE THU THEN BECOME STATIONARY FROM THE FLORIDA PANHANDLE TO EXTREME S TEXAS FRI. REINFORCING SURGE ON SAT WILL ALLOW FRONT TO MOVE S AGAIN BEFORE STALLING AGAIN LATE SUN AND MON. CARIBBEAN SEA... THE UPPER RIDGE OVER THE GULF OF MEXICO COVERS THE NW CARIBBEAN NW OF LINE FROM CUBA NEAR 21N77W TO HONDURAS NEAR 16N85W WITH DRY STABLE AIR ALOFT AS SHOWN ON SATELLITE WATER VAPOR IMAGERY. A SECOND UPPER RIDGE COVERS THE E CARIBBEAN E OF A LINE FROM PUERTO RICO TO LA GUAJIRA PENINSULA OF COLOMBIA. AN UPPER TROUGH EXTENDS FROM THE W ATLC BETWEEN THESE UPPER RIDGES ACROSS HISPANIOLA TO COSTA RICA. CLUSTERS OF SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS DOT THE CENTRAL CARIBBEAN BETWEEN 65W- 80W. THE MONSOON TROUGH EXTENDS FROM COLOMBIA NEAR 10N74W ALONG 11N77W ACROSS NICARAGUA NEAR 12N84W WITH SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS S OF 13N W OF 80W. ISOLATED SHOWERS ARE OVER THE NW CARIBBEAN S OF 19N W OF 80W AND OVER THE E CARIBBEAN FROM 13N-17N E OF 65W TO THE LESSER ANTILLES. WEAK PRESSURE GRADIENT AND BELOW NORMAL TRADE WINDS WILL PREVAIL THROUGH MON. HISPANIOLA... CURRENTLY SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OVER PORTIONS OF THE ISLAND TONIGHT. THE UPPER TROUGH GENERATING THIS ACTIVITY WILL SHIFT E BY FRI. THIS WILL GIVE THE ISLAND A MORE NORTHERLY FLOW ALOFT RESULTING IN A REDUCE CHANCE OF SHOWERS/ THUNDERSTORMS. HOWEVER WITH DAYTIME HEATING AFTERNOON SHOWERS/ ISOLATED THUNDERSTORMS REMAIN A POSSIBILITY. ATLANTIC OCEAN... THE UPPER RIDGE OVER THE GULF OF MEXICO EXTENDS OVER THE W ATLC W OF 73W. AN UPPER TROUGH COVERS THE REMAINDER OF THE W ATLC EXTENDING FROM AN UPPER LOW NEAR 30N66W ACROSS HISPANIOLA INTO THE CENTRAL CARIBBEAN SUPPORTING A SURFACE TROUGH THAT EXTENDS ACROSS BERMUDA ALONG 29N67W 27N71W TO THE BAHAMA ISLANDS NEAR 23N74W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE S OF 22N TO OVER HISPANIOLA BETWEEN 69W-73W AND FROM 26N-30N BETWEEN 62W- 65W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE FROM 21N-26N BETWEEN 59W-71W. A LINGERING STATIONARY FRONT IS IN THE CENTRAL ATLC EXTENDING THROUGH 32N32W ALONG 27N45W TO 32N56W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 60 NM EITHER SIDE OF THE FRONT. A WEAK SURFACE RIDGE COVERS THE E ATLC ANCHORED BY A 1022 MB HIGH OVER THE MADEIRA ISLANDS. THE W ATLC SURFACE TROUGH WILL PERSIST THROUGH FRI. A COLD FRONT WILL ENTER THE FAR NW PORTION LATE SUN AND EXTEND FROM 31N75W TO NE FLORIDA BY LATE MON. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW