000 AXNT20 KNHC 221136 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT OCT 22 2011 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...SPECIAL FEATURES... A BROAD AREA OF LOW PRESSURE COVERS THE SW CARIBBEAN WITH A 1007 MB LOW ANALYZED NEAR 13N81W. LINGERING TROPICAL MOISTURE IS GENERATING SCATTERED/HEAVY SHOWERS WITH ISOLATED THUNDERSTORMS S OF 15N W OF 80W TO INLAND OVER NICARAGUA. ALTHOUGH THERE HAS BEEN LITTLE CHANGE IN THE ORGANIZATION DURING THE PAST SEVERAL HOURS...SURFACE PRESSURES CONTINUE TO FALL OVER THE AREA AND THE DEVELOPMENT OF A TROPICAL DEPRESSION IS STILL POSSIBLE OVER THE NEXT DAY OR TWO. THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 16N17W CONTINUING TO 12N25W. THE ITCZ AXIS CONTINUES FROM 12N25W TO 7N39W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 2N TO INLAND OVER SW AFRICA E OF 2W ACROSS THE PRIME MERIDIAN. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 2N-6N BETWEEN 3W-18W INCLUDING THE COAST OF SW AFRICA AND WITHIN 300 NM S OF THE ITCZ/MONSOON TROUGH BETWEEN 21W-36W. A SURFACE TROUGH IS ANALYZED FROM A 1011 MB LOW NEAR 20N40W SW ALONG 16N43W TO 14N48W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE WITHIN 90/120 NM OF A LINE FROM 16N36W TO 10N45W. A SECOND SURFACE TROUGH IS ALSO IN THE TROPICS EXTENDING FROM 12N49W 10N52W TO INLAND OVER SOUTH AMERICA NEAR 7N58W. SMALL CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 6N-11N BETWEEN 51W-58W. ...DISCUSSION... GULF OF MEXICO... NEAR ZONAL WESTERLY FLOW ALOFT DOMINATES THE GULF THIS MORNING. STRONG SUBSIDENCE AND DRY STABLE AIR ALSO DOMINATES THE GULF WITH SOME LINGERING COLD AIR STRATOCUMULUS CLOUDS ARE OVER THE FAR S GULF LEAVING THE REMAINDER OF THE GULF UNDER MOSTLY CLEAR SKIES AGAIN THIS MORNING. A SURFACE RIDGE COVERS THE GULF AND THE E CONUS WITH A 1022 MB HIGH ALONG COAST OF LOUISIANA NEAR 29N91W. SURFACE RIDGE WILL CONTINUE TO BUILD ACROSS THE W GULF THROUGH WED. CARIBBEAN SEA... THE PRIMARY CONCERN THIS MORNING CONTINUES TO BE THE SURFACE LOW IN THE SPECIAL FEATURES SECTION ABOVE. THE BROAD UPPER TROUGH OVER CENTRAL ATLC EXTENDS OVER THE A MAJOR PORTION OF THE CARIBBEAN INDUCING AN INVERTED UPPER TROUGH OVER THE NW CARIBBEAN FROM NE HONDURAS TO JUST W OF THE CAYMAN ISLANDS. THE REMNANTS OF A STATIONARY FRONTAL BOUNDARY REMAIN ACROSS THE NW CARIBBEAN EXTENDING OVER CUBA NEAR 21N78W TO OVER THE CAYMAN ISLANDS TO E OF HONDURAS NEAR 16N82W. LINGERING MOISTURE COUPLED WITH THE SURFACE AND UPPER LEVEL FEATURES ARE GENERATING HEAVY SHOWERS AND ISOLATED THUNDERSTORMS N OF 15N BETWEEN 79W-87W. THE BROAD UPPER TROUGH IS GENERATING CLUSTERS OF SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS OVER THE CENTRAL AND E CARIBBEAN S OF 19N TO ALONG COAST OF COLOMBIA AND VENEZUELA BETWEEN 65W-80W. REMNANTS OF THE FRONT WILL MEANDER ACROSS THE NW CARIBBEAN THROUGH SUN. A TROUGH OVER THE TROPICAL ATLC WILL MOVE W INTO THE E CARIBBEAN MON REACHING THE CENTRAL CARIBBEAN WED. ATLANTIC OCEAN... THE UPPER TROUGH OVER THE E CONUS EXTENDS OVER THE W ATLC W OF 74W SUPPORTING A STATIONARY FRONT THAT EXTENDS THROUGH 32N69W ALONG 27N72W ACROSS THE BAHAMA ISLANDS NEAR 24N75W TO OVER CUBA NEAR 21N78W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 120 NM W OF THE FRONT S OF 30N TO OVER CUBA. COLD AIR STRATOCUMULUS CLOUDS ARE WITHIN 150 NM W OF THE FRONT. THE SURFACE RIDGE OVER THE GULF OF MEXICO EXTENDS E TO THE FRONT. A BROAD UPPER LOW/TROUGH COVERS THE REMAINDER OF THE W ATLC AND ALL OF THE CENTRAL ATLC CENTERED NEAR 20N64W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 19N-31N BETWEEN 53W-67W. AN UPPER TROUGH EXTENDS S TO OVER THE E ATLC N OF 20N E OF 30W. A BROAD E/W UPPER RIDGE COVERS THE TROPICAL ATLC S OF 20N E OF 58W PROVIDING DIFFLUENCE BETWEEN THIS UPPER RIDGE AND THE ABOVE UPPER TROUGH TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS E OF A LINE FROM 27N21W TO 20N28W TO INLAND OVER THE WESTERN SAHARA. A BROAD SURFACE RIDGE DOMINATES THE ATLC N OF 25N E OF THE FRONT TO AFRICA. THE STATIONARY FRONT WILL DRIFT W THROUGH MON. A COLD FRONT WILL MOVE SE ACROSS THE NW ATLC SUN NIGHT MERGING WITH THE STATIONARY FRONT MON AND THIS MERGED FRONT WILL EXTEND FROM BERMUDA TO THE SE BAHAMAS MON NIGHT THEN MOVE INTO THE CENTRAL ATLC BY EARLY WED. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW