000 AXNT20 KNHC 241745 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST MON NOV 24 2008 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURE... IN THE SW CARIBBEAN...A 1007 MB SURFACE LOW IS CENTERED N OF PANAMA NEAR 10N80W. NUMEROUS SHOWERS AND THUNDERSTORMS ARE ASSOCIATED WITH THIS FEATURE COVERING MOST OF THE AREA SOUTH OF 15N AND WEST OF 76W. SATELLITE IMAGERY REVEALS LITTLE CHANGE IN THE OVERALL ORGANIZATION OF THE CLOUD PATTERN DURING THE PAST SEVERAL HOURS. THERE ARE NO SIGNS OF TROPICAL CYCLONE FORMATION AT THIS TIME AND FURTHER DEVELOPMENT...IF ANY...IS EXPECTED TO BE SLOW. HOWEVER...THIS SYSTEM WILL LIKELY PRODUCE HEAVY RAINS AND LOCALIZED FLOODING OVER PORTIONS OF PANAMA...COSTA RICA... AND NICARAGUA DURING THE NEXT COUPLE OF DAYS. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE CENTRAL CARIBBEAN ALONG 75W S OF 17N MOVING SLOWLY WWD. NOAA BUOY 42058 IS REPORTING NE WINDS OF 30 KT JUST AHEAD OF THE WAVE AXIS. SATELLITE IMAGERY DEPICTS SCATTERED SHOWERS ASSOCIATED WITH THE WAVE WHICH IS EMBEDDED IN AN AREA OF DEEP TROPICAL MOISTURE. THIS WAVE WILL BE ABSORBED BY THE BROAD LOW LEVEL CYCLONIC CIRCULATION ASSOCIATED WITH THE 1007 MB SURFACE LOW NEAR 10N80W. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED ALONG 7N11W 4N25W 7N40W 5N50W 5N57W. SCATTERED MODERATE IS FROM 6N-11N BETWEEN 39W-49W. SIMILAR CONVECTION IS WITHIN 120 NM N OF AXIS BETWEEN 27W-29W. ...DISCUSSION... GULF OF MEXICO... SFC HIGH PRES OVER THE W ATLC...ANALYZED 1030 MB NEAR 36N72W... EXTENDS A RIDGE OVER THE SE CONUS AND MOST OF THE GULF REGION WITH A RELATIVELY COOL AND DRY AIRMASS...AND TEMPERATURES GENERALLY BELOW SEASONAL AVERAGES. SUBSIDENCE AND STABLE ATMOSPHERIC CONDITIONS ARE INHIBITING DEEP CONVECTION ACROSS THE GULF. ALOFT...AN UPPER-LEVEL RIDGE DOMINATES THE ENTIRE AREA. A DEEP-LAYERED TROUGH WHICH IS MOVING ACROSS THE CENTRAL CONUS SUPPORTS A COLD FRONT EXPECTED TO MOVE OFF THE TEXAS COAST THIS AFTERNOON. THE FRONT WILL EXTENDS FROM NEAR THE TAMPA BAY AREA TO THE BAY OF CAMPECHE TOMORROW AFTERNOON AND THEN WILL BE EAST OF THE AREA TUESDAY NIGHT. IN THE WAKE OF THIS FRONT...A REINFORCING COOLER AND DRIER AIRMASS WILL AFFECT THE REGION. AS OF 1500 UTC...A PRE-FRONTAL TROUGH IS ALONG THE TEXAS COASTLINE GENERATING SCATTERED SHOWERS WITH EMBEDDED TSTMS OVER THE NW CORNER OF THE GULF. THE MOSAIC DOPPLER RADAR FROM THE SE CONUS REVEALS THAT THE STRONGEST ACTIVITY IS CURRENTLY N OF 26N AND WEST OF 94W. CARIBBEAN SEA... THE AREA OF INTEREST IN THE TROPICS IS THE 1007 MB SURFACE LOW LOCATED OVER THE SW CARIBBEAN NEAR 10N80W. SEE SPECIAL FEATURE FOR DETAILS. TIGHT PRES GRADIENT BETWEEN THIS SFC LOW AND A RIDGE N OF AREA IS SUPPORTING N TO NE SURFACE WINDS OF 20 TO 30 KT FOR MUCH OF THE CARIBBEAN...WITH THE STRONGEST WINDS OVER THE SW CARIBBEAN AND AROUND THE WINDWARD PASSAGE. SURFACE DATA AND A QSCAT PASS FROM AROUND 1115 UTC CONFIRMED THESE WIND SPEEDS. THE SHOWER AND TSTMS ACTIVITY ASSOCIATED WITH THE AFOREMENTIONED SURFACE LOW IS BEING ENHANCED BY STRONG UPPER LEVEL DIFFLUENCE IN THE VICINITY OF AN UPPER RIDGE PRESENT OVER THE W-CENTRAL CARIBBEAN. THE AXIS OF THIS UPPER RIDGE EXTENDS FROM N COLOMBIA TO THE NW CARIBBEAN INTO THE SE PORTION OF THE GULF OF MEXICO... INCLUDING WESTERN CUBA. A SHORT-WAVE TROUGH IS ALONG 67W AND IS HELPING TO INDUCE SOME SHOWER ACTIVITY OVER THE ISLANDS LOCATED JUST OFF SHORE OF THE VENEZUELA COAST. A BAND OF TRANSVERSE HIGH CLOUDS EXTENDS FROM JAMAICA ACROSS HISPANIOLA...PUERTO RICO AND THE N LEEWARD ISLANDS INTO THE N TROPICAL ATLC. THIS CLOUDS ARE ASSOCIATED WITH STRONG UPPER WESTERLIES WINDS. ATLANTIC OCEAN... OVER THE W ATLC...A RELATIVELY COOL AND DRY AIRMASS IS IN PLACE COURTESY OF A 1030 MB HIGH SITUATED NEAR 36N72W. THIS SYSTEM ENVELOPS THE SE CONUS...THE W ATLC...THE BAHAMAS AND CUBA. A SFC TROUGH HAS DEVELOPED NEAR THE EAST COAST OF FLORIDA AND LIES ALONG 79W FROM 27N-31N. LOW/MID CLOUDS WITH ISOLATED SHOWERS ARE RELATED TO THIS TROUGH. COLD AIR STRATOCUMULUS CLOUDS ARE NOTED OVER THE REMAINDER OF THE W ATLC AND THE BAHAMAS. FARTHER E...AN UPPER-LEVEL TROUGH TILTED FROM NW TO SE OVER THE CENTRAL ATLC CONTINUES TO DIG SOUTHWARD AS A 90-110 KT CYCLONICALLY-CURVED UPPER- LEVEL JET BEGINS TO ROUND THE BASE OF THIS TROUGH. THIS TROUGH SUPPORTS A STATIONARY FRONT THAT ENTERS THE FORECAST AREA NEAR 31N53W THEN CONTINUES SW TO NEAR 27N58W. AHEAD OF THIS FRONT...THERE ARE A COUPLE OF 1012 MB SFC LOWS. ONE IS NEAR 30N53W...THE SECOND ONE IS NEAR 27N54W. THE NORTHERNMOST LOW IS FORECAST TO DEEPEN AS IT MOVES NE OUT OF AREA...WHILE THE SOUTHERNMOST WILL CONTINUE TO WEAKEN. CURRENTLY...SCATTERED TO NUMEROUS MODERATE CONVECTION IS WITHIN 180 NM AHEAD OF THIS LOW N OF 27N. PRES GRADIENT BETWEEN THIS DEVELOPING SFC LOW AND HIGH PRES OVER THE W ATLC WILL RESULT IN GALE FORCE WINDS OF 30 TO 40 KT WITHIN 200 NM W SEMICIRCLE OF THE LOW. ANOTHER 1011 MB SFC LOW IS NEAR 26N30W FORECAST TO MOVE NW BY THE COMPUTER MODELS DURING THE NEXT 24 HOURS. THIS LOW HAS A TROUGH THAT RUNS FROM 28N29W CROSSING THE LOW CENTER TO NEAR 21N38W. AN AREA OF MULTILAYERED CLOUDS WITH ISOLATED TO SCATTERED SHOWERS IS AHEAD OF THE SFC LOW/TROUGH COVERING THE AREA N OF 23N BETWEEN 25W AND 30W. A DIFFLUENT PATTERN ALOFT IS ENHANCING THIS CONVECTIVE ACTIVITY. IN THE TROPICS...A WEAK 1011 MB SFC LOW IS NEAR 13N56W. VIS SATELLITE IMAGERY SHOWS A WELL DEFINED SWIRL OF LOW CLOUDS ASSOCIATED WITH THIS LOW. THE REMAINDER OVER THE E ATLC IS UNDER THE INFLUENCE OF A SFC RIDGE ANCHORED N OF THE AZORES. A JET STREAM BRANCH OF 70-90 KT CROSSES JUST N OF THE CAPE VERDE ISLANDS THEN CONTINUES E-NE OVER WEST AFRICA WITH MAXIMUM WINDS OF 130 KT. $$ GR