000 AXNT20 KNHC 120604 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 07N12W TO 05N20W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 04N34W TO 01N50W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 04N-08N E OF 18W. SCATTERED MODERATE CONVECTION IS WITHIN 160 NM EITHER SIDE OF THE ITCZ BETWEEN 20W- 35W. ...DISCUSSION... GULF OF MEXICO... A 1027 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 ZONE OF UPPER-LEVEL DIVERGENCE THAT ENHANCES SCATTERED MODERATE CONVECTION S OF 13N BETWEEN 73W- 83W. COMBINATION OF HIGH PRESSURE OVER THE NW CARIBBEAN ALONG WITH LOW PRESSURE OVER COSTA RICA...PANAMA AND 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. HISPANIOLA... SHALLOW MOISTURE ASSOCIATED WITH A SURFACE TROUGH N OF THE ISLAND AND BEING ADVECTED FROM THE E CARIBBEAN CONTINUE TO ENHANCE ISOLATED SHOWERS ON THE ISLAND COASTAL WATERS. THESE ISOLATED SHOWERS MAY CONTINUE THROUGH SATURDAY MORNING. HOWEVER...MODEL GUIDANCE INDICATES HIGH MOISTURE FROM THE SW CARIBBEAN WILL MOVE ACROSS THE ISLAND SAT NIGHT THROUGH TUESDAY MORNING...THUS RESUMING THE SHOWER ACTIVITY. NO DEEP CONVECTION IS ANTICIPATED. ATLANTIC OCEAN... THE TAIL OF A DISSIPATING STATIONARY FRONT IS ANALYZED FROM 30N57W TO 26N60W WITH ISOLATED SHOWERS WITHIN 20 NM EITHER SIDE OF THE BOUNDARY. A 1015 MB SURFACE LOW IS LOCATED NEAR 25N41W WITH A TROUGH EXTENDING FROM 29N43W SE TO 23N40W LACKING DEEP CONVECTION. ON THE EASTERN ATLC...A SURFACE TROUGH IS FROM 29N18W TO 25N21W 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