000 AXNT20 KNHC 091801 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST SUN NOV 09 2014 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...THE ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLANTIC NEAR 9N13W TO 7N17W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 4N30W TO 4N40W TO THE COAST OF SOUTH AMERICA NEAR 4N52W. SCATTERED MODERATE CONVECTION IS FROM 3N-12N EAST OF 25W. ISOLATED SHOWERS ARE WITHIN 60 NM S OF THE ITCZ. ...DISCUSSION... GULF OF MEXICO... A MIDDLE- TO UPPER-LEVEL TROUGH IS OVER THE EASTERN CONUS EXTENDING SW TO A BASE OVER THE BAY OF CAMPECHE AND THE YUCATAN PENINSULA. THIS TROUGH ALOFT SUPPORTS A DISSIPATING COLD FRONT ALONG NORTHERN FLORIDA TO NEW ORLEANS WITH ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THE FRONTAL BOUNDARY. THE UPPER TROUGH ALSO SUPPORTS A FRONTAL SYSTEM THAT EXTENDS FROM A 1011 MB LOW AS A COLD FRONT ALONG 26N80W...SOUTH FLORIDA...THE FLORIDA KEYS TO 24N82W...THE YUCATAN CHANNEL TO THE WESTERN YUCATAN PENINSULA NEAR 19N90W. LOW-LEVEL MOISTURE CONVERGENCE ALONG WITH A DIFFLUENT WIND PATTERN ALOFT GENERATED BY A BROAD UPPER RIDGE COVERING THE CARIBBEAN ENHANCE SCATTERED SHOWERS ACROSS SOUTHERN FLORIDA AND WITHIN 140 NM EITHER SIDE OF THE FRONT. STRONG DEEP LAYER ENVIRONMENTAL SHEAR IN THE REGION HINDERS DEVELOPMENT OF DEEP CONVECTION IN THE VICINITY OF THE FRONT AND THE REMAINDER BASIN. NORTHERLY WIND OF 15-20 KT DOMINATE OVER THE GULF...INCREASING TO 25 KT OVER THE BAY OF CAMPECHE. THE COLD FRONT IN THE SE BASIN WILL ENTER THE NW CARIBBEAN SEA TONIGHT WHILE A RIDGE AXIS BUILDS ACROSS THE GULF. THE NEXT COLD FRONT IS FORECAST TO ENTER THE NW BASIN FROM LOUISIANA TO NE MEXICO WED MORNING. CARIBBEAN SEA... HAZY CONDITIONS DOMINATE IN THE NW BASIN INCLUDING CUBA WHERE A TONGUE OF SHALLOW MOISTURE AND STRONG DEEP LAYER ENVIRONMENTAL SHEAR IS OBSERVED. ISOLATED SHOWERS ARE POSSIBLE FOR THIS REGION LATER DURING THE DAY AS A COLD FRONT APPROACHES THE REGION TONIGHT. IN THE SW CARIBBEAN...THE MONSOON TROUGH ENHANCES SCATTERED SHOWERS S OF 11N. ABUNDANT LOW- TO MIDDLE-LEVEL MOISTURE IS ACROSS THE CENTRAL AND EASTERN CARIBBEAN...WHICH ALONG A MIDDLE-LEVEL DIFFLUENT WIND PATTERN SUPPORT SCATTERED SHOWERS WITHIN 60 NM OF A TROUGH AXIS EXTENDING FROM 19N73W TO 9N72W. A SHORT-WAVE ELONGATED UPPER TROUGH OVER THE FAR EASTERN CARIBBEAN SUPPORT RAINSHOWERS OVER THE WINDWARD ISLANDS. A WEAK PRESSURE GRADIENT ACROSS THE BASIN SUPPORT VARIABLE WINDS OF 5 KT TO 10 KT...INCREASING TO 15 KT IN THE EASTERN BASIN. THE COLD FRONT WILL BEGIN TO DISSIPATE ACROSS CENTRAL CUBA TUESDAY MORNING WHILE A SURFACE TROUGH APPROACHES THE EASTERN ISLAND. HISPANIOLA... ABUNDANT LOW- TO MIDDLE-LEVEL MOISTURE ACROSS THE CENTRAL AND EASTERN CARIBBEAN ALONG A MIDDLE-LEVEL DIFFLUENT WIND ENVIRONMENT ENHANCE SCATTERED SHOWERS OVER THE CENTRAL AND WESTERN PORTIONS OF THE ISLAND AS WELL AS ADJACENT WATERS TO INCLUDE THE WINDWARD PASSAGE. THIS RAINSHOWER ACTIVITY IS FORECAST THROUGH TUESDAY MORNING AS THE TROUGH CONTINUES TO DRIFT WESTWARD TO EASTERN CUBA WHERE IT DISSIPATES. ATLANTIC OCEAN... A MIDDLE- TO UPPER-LEVEL TROUGH IS OVER THE EASTERN CONUS AND A PORTION OF THE SW N ATLC...EXTENDING SW TO A BASE OVER THE SW GULF OF MEXICO. THIS TROUGH ALOFT SUPPORTS A FRONTAL SYSTEM ANALYZED AS A STATIONARY FRONT N OF 30N...TRANSITIONING TO A WARM FRONT FROM 30N76W TO A 1011 MB LOW NEAR 28N79W WHERE A COLD FRONT EXTENDS SW TO 26N80W...ACROSS SOUTHERN FLORIDA...THE FLORIDA KEYS TO THE NORTHERN YUCATAN PENINSULA. SCATTERED HEAVY SHOWERS AND ISOLATED TSTMS ARE N OF 25N W OF 75W. SIMILAR CONVECTION IS OBSERVED FARTHER EAST N OF 21N BETWEEN 57W-63W. THE REMAINDER BASIN IS DOMINATED BY SURFACE RIDGING ANCHORED BY A PAIR OF HIGH PRESSURE CENTERS N OF THE AREA OF DISCUSSION. IN THE CENTRAL ATLC...A MIDDLE TO UPPER LEVEL LOW ENHANCES SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS FROM 19N-22N BETWEEN 40W- 44W. THE LOW OVER THE SW N ATLC IS FORECAST TO MOVE N OF 30N DURING TUESDAY AND THE FRONT WILL TRANSITION INTO A COLD FRONT TO MOVE ACROSS THE BAHAMAS THROUGH WEDNESDAY MORNING. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR