000 AXNT20 KNHC 092333 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST FRI JAN 09 2015 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2330 UTC. ...SPECIAL FEATURES... ...GALE-FORCE WINDS IN THE CARIBBEAN SEA... A TIGHT PRESSURE GRADIENT BETWEEN STRONG HIGH PRESSURE OVER THE SOUTHEASTERN US AND LOWER PRESSURE OVER COLOMBIA AND SOUTH AMERICA IS PRODUCING GALE FORCE WINDS WITH SEAS OF 9 TO 12 FEET FROM 11N TO 13N BETWEEN 74W AND 78W. THE GALE FORCE WINDS WILL CONTINUE THROUGH THIS EVENING BEFORE DIMINISHING BELOW WARNING CRITERIA. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND THE OFFSHORE FORECASTS...MIAOFFNT4/FZNT24 KNHC AND MIAOFFNT3/ FZNT23 KNHC FOR MORE DETAILS. ...THE ITCZ/THE MONSOON TROUGH... THE ITCZ EXTENDS FROM THE COAST OF WEST AFRICA AT 09N14W TO 01N29W TO THE COAST OF SOUTH AMERICA AT 00N48W. SCATTERED MODERATE CONVECTION IS WITHIN 100 NM N OF THE AXIS BETWEEN 19W- 42W. ...DISCUSSION... GULF OF MEXICO... A 1040 MB SURFACE HIGH IS CENTERED ACROSS CENTRAL U.S. EXTENDING ITS RIDGE S ACROSS THE BASIN. WITH THIS...A SLIGHT TO GENTLE ANTICYCLONIC FLOW PREVAILS ACROSS THE AREA EXCEPT N OF 26N AND W OF 89W WHERE A MODERATE TO GENTLE BREEZE IS DEPICTED BY SCATTEROMETER DATA AND CURRENT SURFACE OBSERVATIONS. A SURFACE TROUGH IS OVER THE WESTERN GULF WITH AXIS EXTENDING FROM 25N96W TO 21N96W WITH ISOLATED CONVECTION ALONG THIS BOUNDARY. AT UPPER LEVELS...UPPER-LEVEL WESTERLY FLOW IS BRINGING MOISTURE AND CLOUDINESS FROM THE EPAC INTO GULF. OVER THE NEXT 24 HOURS...EXPECT FOR THE SURFACE TROUGH TO CONTINUE NEARLY STATIONARY ACROSS THE W GULF ENHANCING CONVECTION. CARIBBEAN SEA... GALE FORCE WINDS CONTINUE ACROSS THE S CENTRAL CARIBBEAN WATERS N OF COLOMBIA. FOR MORE INFORMATION PLEASE REFER TO THE SPECIAL FEATURES SECTION ABOVE. GENTLE TO MODERATE TRADES PREVAIL ACROSS THE REMAINDER OF THE BASIN. A SURFACE TROUGH EXTENDS ACROSS THE VIRGIN ISLANDS WITH AXIS FROM 20N61W TO 17N64W. SAN JUAN DOPPLER RADAR IMAGERY SHOWS SHALLOW CONVECTION MOVING QUICKLY W ACROSS THE BASIN AFFECTING HISPANIOLA...PUERTO RICO AND THE LESSER ANTILLES. AT UPPER LEVELS...UPPER-LEVEL WESTERLY FLOW IS BRINGING MOISTURE AND CLOUDINESS FROM THE EPAC INTO THE W CARIBBEAN. AN UPPER-LEVEL TROUGH IS OVER THE CENTRAL CARIBBEAN WITH AXIS ALONG 75W. UPPER-LEVEL RIDGING PREVAILS ACROSS THE FAR E CARIBBEAN SUPPORTING SUBSIDENCE. OVER THE NEXT 24 HOURS...EXPECT FOR THE TROUGH TO CONTINUE MOVING W APPROACHING HISPANIOLA ENHANCING CONVECTION. HISPANIOLA... MOSTLY FAIR WEATHER PREVAILS OVER THE ISLAND. EXPECT WITHIN 24 HOURS FOR FOR THE SURFACE TROUGH OVER THE VIRGIN ISLANDS TO APPROACH EASTERN HISPANIOLA ENHANCING CONVECTION. ATLANTIC OCEAN... A FRONTAL BOUNDARY IS DEVELOPING ACROSS THE W ATLANTIC AND MOVING E EXTENDING FROM 28N81W TO 32N77W THEN N INTO THE NW ATLANTIC. TO THE E...THE TAIL END OF A QUASI-STATIONARY FRONT EXTENDS FROM 27N63W TO 31N55W. A PRE-FRONTAL TROUGH IS FROM 26N57W TO 30N54W. SURFACE HIGH PRESSURES PREVAIL ACROSS THE REMAINDER OF THE BASIN WITH FAIR WEATHER. AN UPPER-LEVEL LOW CENTERED NEAR 17N42W IS ENHANCING ISOLATED CONVECTION FROM 15N- 20N BETWEEN 29W-42W. EXPECT OVER THE NEXT 24 HOURS FOR THE FRONTAL BOUNDARY ACROSS THE W ATLANTIC TO MOVE SE NEAR THE FLORIDA STRAITS. THE STATIONARY FRONT OVER THE CENTRAL ATLANTIC WILL DISSIPATE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ ERA