000 AXNT20 KNHC 301742 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST MON DEC 30 2013 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 1715 UTC. ...SPECIAL FEATURES... A COLD FRONT CURRENTLY ANALYZED ACROSS THE NW GULF OF MEXICO ALONG WITH AN AREA OF LOW PRESSURE FOCUSED ON A 1015 MB LOW CENTERED NEAR 25N96W IS EXPECTED TO PRODUCE GALE FORCE N-NW WINDS FROM 21N-25N W OF THE FRONT BY 30/1800 UTC. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 10N14W TO 06N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N20W TO 04N26W TO 03N37W TO THE EQUATOR NEAR 46W. ISOLATED MODERATE CONVECTION IS FROM 03N-08N BETWEEN 34W-46W. ...DISCUSSION... GULF OF MEXICO... A VIGOROUS MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE SOUTHERN GULF OF CALIFORNIA NEAR 25N109W THAT IS PROVIDING MUCH OF THE GULF WITH SOUTHWESTERLY MIDDLE TO UPPER LEVEL FLOW ALOFT. A 540 NM WIDE BAND OF MOISTURE IS NOTED ON WATER VAPOR IMAGERY ON THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW CONTINUING TO ADVECT CLOUDINESS AND MOISTURE NORTHEASTWARD ACROSS CENTRAL AND NE MEXICO...AND MUCH OF THE WESTERN GULF THIS AFTERNOON. AT THE SURFACE...A COLD FRONT ANALYZED FROM 30N93W S-SW TO 24N98W IS CURRENTLY MERGING WITH A DEVELOPING AREA OF LOW PRESSURE FOCUSED ON A 1015 MB LOW CENTERED NEAR 25N96W AND THE ASSOCIATED SURFACE TROUGH AXIS EXTENDING SOUTHWARD TO 21N97W. SATELLITE IMAGERY AND MOSAIC DOPPLER RADAR IMAGERY INDICATE NUMEROUS SHOWERS AND ISOLATED TSTMS OCCURRING N OF 23N W OF A LINE FROM MOBILE BAY NEAR 30N88W TO 23N94W. THE PRESSURE GRADIENT BETWEEN THIS DEVELOPING LOW AND A RIDGE TO THE NORTHWEST IS EXPECTED TO STRENGTHEN THROUGH EARLY TUESDAY WITH GALE FORCE NORTHERLY WINDS COMMENCING BY THIS AFTERNOON ACROSS PORTIONS OF THE WESTERN GULF. THE LOW IS FORECAST TO DRIFT SE THROUGH LATE TUESDAY AND SLOWLY BEGIN TO LIFT NORTH-NORTHEASTWARD BY EARLY THURSDAY. OTHERWISE...ACROSS THE SE GULF...A STATIONARY FRONT IS ANALYZED ACROSS THE SOUTHERN FLORIDA PENINSULA AND SE GULF FROM 27N80W TO 24N83W TO 22N88W. A SURFACE TROUGH IS NOTED TO THE SOUTH OF THE FRONT FROM THE YUCATAN CHANNEL AND ALONG THE EASTERN YUCATAN COAST. ISOLATED SHOWERS AND TSTMS ARE POSSIBLE S OF 26N BETWEEN 81W-88W. CARIBBEAN SEA... THE CARIBBEAN IS UNDER THE INFLUENCE OF WEST TO NORTHWESTERLY FLOW ALOFT. WATER VAPOR IMAGERY INDICATES THE AIRMASS TO BE VERY DRY AND STABLE WITH CONFLUENCE ALOFT MAXIMIZED OVER THE EASTERN CARIBBEAN E OF 72W. AT THE SURFACE...THE MAIN FEATURE IS A PRE- FRONTAL SURFACE TROUGH ANALYZED FROM THE YUCATAN CHANNEL NEAR 22N86W TO 20N88W TO 17N88W. ISOLATED SHOWERS ARE OCCURRING IN THE VICINITY OF THE YUCATAN CHANNEL REGION AND AREAS SOUTH FROM 15N-22N BETWEEN 85W-90W...INCLUDING THE GULF OF HONDURAS AND INLAND PORTIONS OF CENTRAL AMERICA. OTHERWISE...TRADES PERSIST IN THE RANGE OF 15 TO 25 ELSEWHERE S OF 18N WITH THE STRONGEST SPEEDS NOTED ON RECENT SCATTEROMETER DATA BETWEEN 68W-80W AND IN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. 25 TO 30 KT NE TO E WINDS WERE DEPICTED ON THE MOST RECENT 29/1412 UTC ASCAT PASS S OF 14N BETWEEN 72W-78W. ISOLATED LOW-TOPPED SHOWERS ARE EXPECTED TO CONTINUE RIDING WESTWARD ON THE TRADES THIS AFTERNOON INTO THE EVENING AND OVERNIGHT PERIOD. ...HISPANIOLA... CURRENTLY ONLY A FEW PASSING TRADEWIND LOW-TOPPED SHOWERS ARE IMPACTING THE EASTERN HALF OF THE ISLAND THIS AFTERNOON WITH PLENTY MORE ISOLATED SHOWER ACTIVITY TO THE EAST AS NOTED ON SATELLITE IMAGERY AND SAN JUAN PUERTO RICO DOPPLER RADAR IMAGERY. THE QUICK PASSING SHOWERS SHOULD CONTINUE THROUGH THE NEXT 24 TO 36 HOURS WITH NO SIGNIFICANT DEEP CONVECTION EXPECTED DUE TO DRY AND VERY STABLE NORTH-NORTHWESTERLY WINDS ALOFT. ATLANTIC OCEAN... BROAD MIDDLE TO UPPER LEVEL TROUGHING IS NOTED ACROSS THE EASTERN CONUS THAT SUPPORTS A 988 MB LOW CENTERED NEAR NOVA SCOTIA CANADA THIS AFTERNOON. THE ASSOCIATED COLD FRONT EXTENDS S-SW FROM THE LOW CENTER INTO THE DISCUSSION AREA NEAR 32N73W THEN SW TO THE SOUTHERN FLORIDA PENINSULA NEAR 27N80W. LOW-LEVEL MOISTURE CONVERGENCE IN THE VICINITY OF THE FRONT ALONG WITH MIDDLE TO UPPER LEVEL DIFFLUENCE EAST OF THE TROUGH AXIS IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS WITHIN 150 NM EAST OF THE FRONT. OVER THE EASTERN ATLC...AN UPPER LEVEL TROUGH AXIS EXTENDS FROM 35N28W SW TO A BASE NEAR 17N59W. THE TROUGHING ALOFT SUPPORTS A COLD FRONT ANALYZED FROM 33N30W TO 32N34W AND BECOMES STATIONARY TO 28N39W TO 27N46W. WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF THE FRONT. FINALLY...THE FRONTAL BOUNDARY IS FOUND BETWEEN TWO SURFACE RIDGES...ONE ANCHORED BY A 1030 MB HIGH CENTERED NEAR 34N43W AND THE OTHER SURFACE RIDGE ANCHORED BY A 1030 MB HIGH CENTERED WEST OF THE MADEIRA ISLANDS NEAR 33N19W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN