000 AXNT20 KNHC 121133 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST FRI DEC 12 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 07N12W TO 07N18W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 03N34W TO 02N50W. SCATTERED MODERATE CONVECTION IS FROM 02N-10N E OF 52W. ...DISCUSSION... GULF OF MEXICO... A 1028 MB HIGH CENTERED OVER SE MISSOURI ALONG WITH A MODERATE N- S PRESSURE GRADIENT CONTINUE TO ALLOW COLD AIR ADVECTION WITH N- NE WINDS OF 5 TO 15 KT ACROSS THE BASIN EXCEPT FOR THE NW GULF WHERE SE RETURN FLOW OF SIMILAR MAGNITUDE PREVAILS. NO SIGNIFICANT DEEP CONVECTION IS OCCURRING UNDER GENERALLY DRY AND SUBSIDENT FLOW AT THE MIDDLE TO LOWER LEVELS. LITTLE CHANGE IS EXPECTED AT THE SURFACE FOR THE NEXT COUPLE OF DAYS AS THE HIGH REMAINS RATHER LOCKED IN PLACE OVER THE SOUTHEAST UNITED STATES. IN THE UPPER-LEVELS...THE SUBTROPICAL JET STREAM CONTINUES TO SUPPORT STRONG WESTERLIES OVER THE GULF...WHICH ADVECT MOISTURE AND HIGH CLOUDS FROM THE EPAC WATERS...HOWEVER WITH NO SIGNIFICANT PRECIPITATION. CARIBBEAN SEA... MODERATE MOISTURE IS BEING ADVECTED FROM THE SW-CENTRAL ATLC INTO THE EASTERN AND NORTHERN-CENTRAL CARIBBEAN...THUS ENHANCING ISOLATED SHOWERS ACROSS THE LESSER ANTILLES AND HISPANIOLA COASTAL WATERS. ABUNDANT MOISTURE CONTINUES OVER THE SW CARIBBEAN BASIN COINCIDING WITH A DIVERGENT ENVIRONMENT ALOFT THAT ENHANCES SCATTERED MODERATE CONVECTION S OF 13N W OF 77W. COMBINATION OF HIGH PRESSURE OVER THE NW CARIBBEAN ALONG WITH LOW PRESSURE OVER COSTA RICA...PANAMA AND NORTHERN COLOMBIA CONTRIBUTE TOWARD 20-25 KT NE WINDS OVER THE SOUTHWESTERN CARIBBEAN. ELSEWHERE...THE TRADEWINDS ARE GENERALLY 10-20 KT AND NO DEEP CONVECTION IS OCCURRING SUPPORTED BY SUBSIDENT AND DRY MID- TO UPPER-LEVEL WESTERLY TO SOUTHWESTERLY FLOW. COOL AIR ADVECTION IS FORECAST TO CONTINUE ACROSS THE NW CARIBBEAN DURING THE NEXT TWO DAYS. THE PRESSURE GRADIENT IN THE SW CARIBBEAN IS FORECAST TO RELAX THIS AFTERNOON WHILE THE LOW DISSIPATES...THUS LEADING TO DIMINISHED WINDS. HISPANIOLA... SHALLOW MOISTURE ASSOCIATED WITH A SURFACE TROUGH N OF THE ISLAND AS WELL AS ADVECTED FROM THE E CARIBBEAN CONTINUE TO ENHANCE ISOLATED SHOWERS ON THE ISLAND COASTAL WATERS AND EASTERN DOMINICAN REPUBLIC. THESE ISOLATED SHOWERS MAY CONTINUE THROUGH SATURDAY MORNING. HOWEVER...MODEL GUIDANCE INDICATES HIGH MOISTURE FROM THE SW CARIBBEAN WILL MOVE NE ACROSS THE ISLAND SAT NIGHT THROUGH TUESDAY MORNING...THUS RESUMING THE SHOWER ACTIVITY. NO DEEP CONVECTION IS ANTICIPATED. ATLANTIC OCEAN... A DISSIPATING STATIONARY FRONT IS ANALYZED FROM 30N59W TO 22N68W WHERE IT TRANSITIONS INTO A SURFACE TROUGH TO EASTERN CUBA. ISOLATED SHOWERS ARE WITHIN 100 NM EITHER SIDE OF THE FRONT N OF 24N AND WITHIN 120 NM W OF THE TROUGH AXIS. A 1014 MB SURFACE LOW IS LOCATED NEAR 24N43W LACKING DEEP CONVECTION. ON THE EASTERN ATLC...A SURFACE TROUGH IS ALONG 32N30W TO 28N36W ENHANCING SCATTERED SHOWERS FROM 27N-32N BETWEEN 31W-34W. A SECOND SURFACE TROUGH IS FROM 30N15W TO 25N22W ENHANCING SHOWERS ACROSS THE CANARY ISLANDS. SURFACE RIDGING DOMINATES ELSEWHERE. IT IS ANTICIPATED THAT THE LOW WILL DISSIPATE IN ABOUT A DAY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR