000 AXNT20 KNHC 220603 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SAT NOV 22 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL WEST AFRICA NEAR 10N14W TO 8N18W WHERE THE ITCZ CONTINUES ALONG 6N30W TO 6N40W 6N54W. SCATTERED MODERATE CONVECTION IS FROM 4N-13N E OF 23W AND WITHIN 130 NM EITHER SIDE OF THE ITCZ WEST OF 23W. ...DISCUSSION... ...THE GULF OF MEXICO... A MIDDLE- TO UPPER-LEVEL RIDGE OVER THE EASTERN CONUS CONTINUES TO SUPPORT A BROAD SURFACE ANTICYCLONE ANCHORED BY A 1035 MB HIGH ON WEST VIRGINIA...WHICH EXTENDS SW ACROSS FLORIDA TO THE SOUTHERN GULF OF MEXICO. A TIGHT PRESSURE GRADIENT OF THIS RIDGE OVER THE EASTERN GULF SUPPORT EASTERLY WIND OF 20-25 KT WHILE A MORE RELAXED PRESSURE GRADIENT WEST OF 90W PROVIDES FOR E-SE WIND FLOW OF 15-20 KT. DEEP LAYER DRY AIR IN THE NORTHERN GULF N OF 26N MAINTAINS FAIR WEATHER IN THIS REGION. MIDDLE- TO LOW-LEVEL MOISTURE ADVECTION FROM THE CARIBBEAN SEA AS WELL AS UPPER-LEVEL MOISTURE STREAMING NE FROM THE E PAC WATERS SUPPORT CLOUDINESS AND ISOLATED SHOWERS ACROSS THE REMAINDER GULF. A STATIONARY FRONT EXTENDING ACROSS THE CENTRAL BAHAMAS SW TO WESTERN CUBA SUPPORT SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ACROSS THE FLORIDA STRAITS. AS THE SURFACE RIDGE ANCHORED OVER WEST VIRGINIA CONTINUES TO DRIFT SE DURING THE NEXT TWO DAYS...A COLD FRONT WILL START ENTERING THE NW BASIN EARLY MONDAY. ...THE CARIBBEAN SEA... SHALLOW MOISTURE MOVES ACROSS THE CENTRAL AND WESTERN CARIBBEAN SEA...HOWEVER DRY AIR SUBSIDENCE ASSOCIATED WITH AN UPPER-LEVEL ANTICYCLONE OVER THIS REGION HINDER THE DEVELOPMENT OF CONVECTION. THE TAIL OF A STATIONARY FRONT CONTINUES OVER WESTERN CUBA FROM WHERE A SURFACE TROUGH EXTENDS ALONG 21N85W TO 16N87W. ISOLATED SHOWERS ARE NOTED WITHIN 20 NM OF THE COASTS OF BELIZE...HONDURAS...NICARAGUA AND PANAMA. AN UPPER-LEVEL LOW OVER THE NE BASIN ALONG WITH A BROAD MOIST AIRMASS MOVING ACROSS THE EASTERN CARIBBEAN SUPPORT SCATTERED HEAVY SHOWERS OVER THE LESSER ANTILLES AND THE VIRGIN ISLANDS. SIMILAR CONVECTION IS EXPECTED FOR PUERTO RICO AND ADJACENT WATERS THIS TONIGHT AND THROUGH SATURDAY. THE TROUGH IS FORECAST TO DISSIPATE SAT MORNING. ...HISPANIOLA... CURRENTLY FAIR WEATHER IS ACROSS THE ISLAND AND ADJACENT WATERS BEING INFLUENCED BY DRY AIR SUBSIDENCE ASSOCIATED WITH AN UPPER- LEVEL ANTICYCLONE OVER THE WESTERN AND CENTRAL CARIBBEAN. HOWEVER...BY SATURDAY MORNING...A BROAD AND MOIST AIRMASS STARTS TO MOVE ACROSS THE ISLAND ENHANCING SCATTERED HEAVY SHOWERS AND TSTMS. SHOWERS ASSOCIATED WITH THE PASSAGE OF THIS AIRMASS ACROSS THE ISLAND ARE FORECAST THROUGH SUNDAY NIGHT. ...THE ATLANTIC OCEAN... A BROAD MIDDLE- TO UPPER-LEVEL TROUGH OVER THE NW ATLC CONTINUES TO SUPPORT A COLD FRONT ALONG 34N53W SW TO 27N65W TO 25N71W WHERE IT TRANSITIONS TO A STATIONARY FRONT THAT EXTENDS ACROSS THE NORTHERN-CENTRAL BAHAMAS TO WESTERN CUBA. SCATTERED SHOWERS ARE WITHIN 180 NM WEST OF THE FRONTAL BOUNDARY...SIMILAR SHOWER ACTIVITY IS WITHIN 180 NM EAST OF THE FRONT N OF 26N. SCATTERED HEAVY SHOWERS AND ISOLATED TSTMS ARE WITHIN 120 NM N OF THE VIRGIN ISLANDS AND EAST OF THE LESSER ANTILLES BEING ENHANCED BY A BROAD MOIST AIRMASS MOVING ACROSS THE EASTERN CARIBBEAN. ON THE FAR NE ATLC BASIN...A 1004 MB LOW IS EAST OF THE CANARY ISLANDS SUPPORTING SCATTERED HEAVY SHOWERS N OF 27N E OF 13W. SURFACE RIDGING DOMINATES ELSEWHERE ACROSS THE BASIN N OF 20N. A RIDGE ANCHORED OVER WEST VIRGINIA MOVING SE OVER THE NEXT THREE DAYS WILL CONTINUE TO DRIFT THE COLD FRONT TOWARDS THE CENTRAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR