000 AXNT20 KNHC 170546 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST WED DEC 17 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 CROSSES THE AFRICAN COAST NEAR 06N11W AND CONTINUES OVER THE EASTERN ATLANTIC TO NEAR 05N14W. THE ITCZ BEGINS AT 05N14W AND CONTINUES TO 07N30W TO 05N33W TO THE COAST OF SOUTH AMERICA AT 02N50W. SCATTERED MODERATE CONVECTION IS FROM 02N-10N BETWEEN 18W-36W. ...DISCUSSION... GULF OF MEXICO... A COLD FRONT EXTENDS FROM THE FLORIDA PANHANDLE AT 30N84W TO THE NORTH CENTRAL GULF OF MEXICO NEAR 26N89W TO 25N96W. A STATIONARY FRONT EXTENDS FROM 25N96W TO N MEXICO NEAR 28N103W. NO CONVECTION IS RELATED TO THESE BOUNDARIES. 10-15 KT NORTHERLY WINDS PREVAIL BEHIND THE FRONT WHILE 5-10 KT EASTERLY WINDS ARE S OF THE FRONT. AT UPPER LEVELS...ZONAL FLOW IS OVER THE GULF WITH STRONG SUBSIDENCE. EXPECT IN 24 HOURS FOR THE COLD FRONT TO CONTINUE MOVING S ACROSS THE FLORIDA PENINSULA REACHING SOUTH FLORIDA WHILE ENHANCING CONVECTION. CARIBBEAN SEA... THE TAIL END OF A STATIONARY FRONT EXTENDS FROM THE ATLANTIC ACROSS THE E PORTION OF THE BASIN FROM 18N63W TO 18N76W. A SHEAR LINE EXTENDS FROM 18N76W TO 10N82W. ISOLATED MODERATE CONVECTION IS PRESENT ALONG THE SHEAR LINE AND N OF THE FRONTAL BOUNDARY FROM 18N-20N BETWEEN 71W-77W. 15-20 KT NORTHERLY WINDS ARE OVER THE W CARIBBEAN W OF THE SHEARLINE WHILE 5-15 KT EASTERLIES ARE E OF THE SHEARLINE. AT UPPER LEVELS...RIDGING IS PREVAILING OVER THE CARIBBEAN PRODUCING SW TO W FLOW. STRONG SUBSIDENCE CONTINUES OVER MOST OF THE BASIN EXCEPT OVER THE FRONT AND SHEARLINE. EXPECT OVER THE NEXT 24 HOURS FOR THE FRONT TO WEAKEN AND THE SHEARLINE PERSISTING ENHANCING CONVECTION. HISPANIOLA... THE TAIL END OF A STATIONARY FRONT IS S OF THE ISLAND KEEPING THE SOUTHERN PORTION OF HAITI WITH SCATTERED CONVECTION. EXPECT OVER THE NEXT 24 HOURS FOR THESE CONDITIONS TO PERSIST. ATLANTIC OCEAN... A PAIR OF 1022 MB SURFACE HIGH PRESSURE CENTERS ARE ACROSS THE W ATLANTIC SUPPORTING FAIR WEATHER. TO THE E...AN UPPER-LEVEL TROUGH WITH AXIS NEAR 51W IS SUPPORTING A FRONTAL BOUNDARY THAT BEGINS AS A COLD FRONT ACROSS THE N ATLANTIC AND THEN BECOMES STATIONARY FROM 30N44W TO 18N65W INTO THE CARIBBEAN. SCATTERED MODERATE CONVECTION IS PRESENT AHEAD OF THE FRONT SUPPORTED BY UPPER-LEVEL DIFFLUENCE MAINLY N OF 21N BETWEEN 38W-44W. A 1039 MB HIGH PRESSURE CONTINUES ACROSS THE E ATLANTIC CENTERED NEAR 39N23W SUPPORTING FAIR WEATHER. EXPECT OVER THE NEXT 24 HOURS FOR THE FRONT TO PERSIST ACROSS THE BASIN ENHANCING CONVECTION. A NEW COLD FRONT WILL BE APPROACHING THE W ATLANTIC AS IT MOVES ACROSS THE FLORIDA PENINSULA ON TODAY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ ERA