000 AXNT20 KNHC 280530 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SAT SEP 28 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 0445 UTC. ...SPECIAL FEATURE... A SMALL LOW PRESSURE SYSTEM LOCATED ABOUT 700 NM E-NE OF THE N LEEWARD ISLANDS IS PRODUCING WINDS TO NEAR GALE FORCE AND IS ANALYZED AS A 1014 MB LOW NEAR 21N50W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 120 NM OF LINE FROM 15N47W TO 26N50W. UPPER LEVEL WINDS COULD BECOME MORE CONDUCIVE FOR DEVELOPMENT OVER THE NEXT COUPLE OF DAYS WHILE THE LOW MOVES N AND THEN NE AT 9-13 KT. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... TROPICAL WAVE OFF THE COAST OF AFRICA EXTENDS FROM 17N18W TO 8N21W MOVING W 10-15 KT. WAVE IS EMBEDDED WITHIN A SURGE OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. NO ASSOCIATED CONVECTION. TROPICAL WAVE EXTENDS FROM 19N53W TO 9N52W MOVING W 10-15 KT. WAVE REMAINS WITHIN A MODERATE AMOUNT MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. THE DEEPEST MOISTURE IS THE W OF THIS WAVE AND ASSOCIATED WITH THE LOW IN THE SPECIAL FEATURES. NO ASSOCIATED CONVECTION. TROPICAL WAVE EXTENDS FROM GUADELOUPE IN THE LEEWARD ISLANDS ALONG 12N62W TO OVER VENEZUELA TO 7N61W MOVING W NEAR 15 KT. WAVE IS ALONG THE LEADING EDGE OF MODERATE MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. WAVE IS AT THE BASE OF AN UPPER TROUGH WITH NO ASSOCIATED CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 12N16W THROUGH TO 8N23W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 7N26W 8N33W TO 5N43W. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 150 NM N OF THE ITCZ BETWEEN 37W-42W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 5N-12N BETWEEN 22W-29W AND WITHIN 75 NM OF LINE FROM 7N42W TO 9N49W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE DOMINATES THE NW GULF ANCHORED OVER E TEXAS. A SHORTWAVE UPPER TROUGH CUTS ACROSS THE S/CENTRAL GULF FROM A BROAD UPPER TROUGH OVER THE E GULF AND W ATLC FROM MERIDA ON THE YUCATAN PENINSULA TO TAMPICO MEXICO. THIS BROAD UPPER TROUGH IS SUPPORTING A COLD FRONT THAT AT 28/0300 UTC EXTENDS FROM THE W ATLC ALONG THE N COAST OF CUBA NEAR 23N80W TO 23N84W WHERE IT BECOMES STATIONARY TO 24N91W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60 NM OF THE COLD FRONT WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 45 NM OF THE STATIONARY FRONT. A SURFACE RIDGE IS BUILDING S OVER THE GULF ANCHORED BY A 1026 MB HIGH OVER NEW ENGLAND. WATER VAPOR IMAGERY INDICATED DRY STABLE AIR COVERS ALL BUT THE FAR SW GULF KEEPING THE REMAINDER OF THE AREA UNDER MOSTLY CLEAR SKIES TONIGHT. WEAK FRONT WILL CONTINUE TO DISSIPATE OVER THE WEEKEND. SURFACE RIDGE WILL CONTINUE TO BUILD S THROUGH SAT. THIS WEAK SURFACE RIDGE WILL DOMINATE THE REGION SUN THROUGH TUE. CARIBBEAN SEA... THE UPPER TROUGH OVER THE E GULF OF MEXICO DIPS S OVER THE NW CARIBBEAN N OF 14N W OF 80W. AN UPPER RIDGE IS ANCHORED OVER SOUTH AMERICA COVERING THE CENTRAL CARIBBEAN S OF 20N BETWEEN 70W-80W. SCATTERED SHOWERS/THUNDERSTORMS ARE N OF 18.5N TO OVER HAITI AND THE GULF OF GONAVE INCLUDING THE WINDWARD PASSAGE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE N OF 20N TO INLAND OVER CUBA BETWEEN 77W-81W. CLUSTERS OF SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE FROM 12N-16N BETWEEN 74W-83W. THE MONSOON TROUGH EXTENDS FROM COLOMBIA OVER PANAMA CLIPPING THE FAR SW CARIBBEAN GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS S OF 10N. AN UPPER TROUGH COVERS THE E CARIBBEAN EXTENDING FROM AN UPPER LOW OVER THE CENTRAL ATLC. EASTERLY TRADE WINDS WILL PREVAIL THROUGH WED. BROAD AREA OF LOW PRESSURE IS FORECAST TO FORM ACROSS THE SW CARIBBEAN DURING THE WEEKEND THEN WILL DRIFT TOWARD THE NW CARIBBEAN THROUGH WED. HISPANIOLA... SCATTERED SHOWERS/THUNDERSTORMS ARE OVER HAITI AND THE GULF OF GONAVE FROM 18.5N TO 21N BETWEEN 71W-74W INCLUDING THE WINDWARD PASSAGE. THIS IS LEAVING MOST OF THE DOMINICAN REPUBLIC UNDER CLEAR SKIES TONIGHT. THE UPPER TROUGH OVER THE W ATLC AND NW CARIBBEAN IS GIVING HAITI SOUTHERLY FLOW ALOFT TONIGHT AND WILL CONTINUE THROUGH EARLY MON WHEN WINDS WILL SHIFT MORE WESTERLY. THIS WILL INCREASE THE CHANCE OR INTENSIFY AFTERNOON SHOWERS AND THUNDERSTORMS THROUGH THE WEEKEND. ATLANTIC OCEAN... AN UPPER TROUGH COVERS THE W ATLC W OF 70W ACROSS FLORIDA INTO THE E GULF OF MEXICO AND DIPS S OVER THE NW CARIBBEAN SUPPORTING A COLD FRONT THAT AT 28/0300 UTC ENTERS THE REGION NEAR 32N56W AND EXTENDS ALONG 28N63W WHERE IT BECOMES STATIONARY TO A 1006 MB LOW NEAR 28N72W THEN CONTINUES ALONG 24N72W THROUGH THE BAHAMA ISLANDS INTO THE GULF OF MEXICO NEAR 23N80W. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 75 NM ALONG THE FRONTS W OF 62W. A WEAKENING UPPER RIDGE STRETCHES FROM 28N62W TO OVER PUERTO RICO ENHANCING THE ACTIVITY OVER HAITI AND GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60 NM OF LINE FROM 24N67W TO 26N63W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE FROM 22N-30N BETWEEN 57W-62W. AN UPPER LOW IS IN THE CENTRAL ATLC NEAR 24N57W EXTENDING AN UPPER TROUGH ALONG 18N59W TO OVER THE E CARIBBEAN NEAR GUADELOUPE. THE REMAINDER OF THE ATLC IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1022 MB HIGH NEAR 25N39W. THE 1006 MB LOW WILL MOVE SLOWLY E-NE THROUGH SAT THEN ACCELERATE NE SAT NIGHT THROUGH MON. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW