000 AXNT20 KNHC 281743 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST FRI JAN 28 2011 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED ALONG 5N9W TO 2N20W CROSSING THE EQUATOR AT 30W TO 2S44W. ISOLATED MODERATE CONVECTION S OF THE ITCZ TO 3N BETWEEN 9W AND 11W. NO SIGNIFICANT CONVECTION ELSEWHERE. ...DISCUSSION... GULF OF MEXICO... AT 28/1500 UTC...A 1025 MB HIGH CENTERED OVER THE NW GULF NEAR 27N94W DOMINATES MOST OF THE REGION PRODUCING RELATIVELY TRANQUIL CONDITIONS. SOME STRATOCUMULUS CLOUDS ARE STILL NOTED ACROSS PORTIONS OF THE CENTRAL AND NE GULF AS COOLER AIR RUNS OVER THE WARMER WATER. MORE WIDESPREAD LOW-LEVEL CLOUDINESS AND POSSIBLE ISOLATED SHOWERS REMAIN ALONG THE ERN COAST OF MEXICO. A RE-INFORCING COLD FRONT IS MOVING ACROSS SOUTH FLORIDA AND THE SE PORTION OF THE GULF...AND WILL EXIT THE SUNSHINE STATE LATE THIS AFTERNOON INTO THIS EVENING. MAINLY ZONAL WLY FLOW ALOFT DOMINATES THE REGION ADVECTING MID/UPPER LEVEL MOISTURE FROM THE EPAC. EXPECT THE SURFACE RIDGE TO GRADUALLY DRIFT EWD ACROSS THE BASIN REACHING FLORIDA BY EARLY SUNDAY. THE NEXT COLD FRONT IS FORECAST TO APPROACH THE TEXAS COAST BY TUE. SLY RETURN FLOW WILL INCREASE AHEAD OF THE FRONT. CARIBBEAN SEA... THE FRONT THAT WAS OVER FAR NW CARIBBEAN YESTERDAY HAS DISSIPATED. LINGERING MOISTURE WITH EMBEDDED SHOWERS IS SEEN ON SATELLITE PICTURES OVER THE GULF OF HONDURAS DUE TO LOW LEVEL CONVERGENCE. SURFACE DATA AND AN EARLIER ASCAT PASS SHOW FRESH NORTHERLY WINDS THROUGH THE YUCATAN CHANNEL AND THE WESTERN CARIBBEAN. THESE WINDS ARE EXPECTED TO DIMINISH THROUGH THIS EVENING AS WINDS GRADUALLY VEER MORE NE ACROSS THE W CARIBBEAN. ANOTHER PATCH OF MOISTURE WITH SHOWERS AND ISOLATED TSTMS COVERS THE AREA FROM 12N-16N BETWEEN 80W-84W. IT IS ALSO ASSOCIATED WITH LOW LEVEL CONVERGENCE. FRESH TRADE WINDS WILL CONTINUE TO BLOW FROM THE TROPICAL N ATLC THROUGH THE CENTRAL CARIBBEAN THROUGH EARLY NEXT WEEK. PATCHES OF LOW LEVEL MOISTURE EMBEDDED IN THE TRADE WIND FLOW ARE EXPECTED TO MOVE ACROSS THE BASIN FROM TIME TO TIME...RESULTING IN INTERVALS OF CLOUDINESS AND A FEW PASSING SHOWERS. THESE SHALLOW SHOWERS ARE CURRENTLY MORE CONCENTRATED OVER THE CENTRAL CARIBBEAN FROM 14N-18N BETWEEN 72W-77W. THE BASE OF THE MAINLY ZONAL WLY FLOW ALOFT EXTENDS FURTHER SOUTH OVER THE N PORTION OF THE CARIBBEAN SEA. WATER VAPOR IMAGERY REVEALS MODERATE TO STRONG SUBSIDENCE OVER THE MAJORITY OF THE BASIN BUT PARTICULARLY E OF 70W. THE ATLANTIC OCEAN... A DEEP LAYER TROUGH IS OVER THE EASTERN U.S. SUPPORTING A RE-INFORCING COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 31N74W THEN CONTINUES SW TO SOUTH FLORIDA. BASED ON THE COMPUTER MODELS...THIS FRONT WILL BECOME ILL DEFINED IN ABOUT 24 HOURS. ANOTHER COLD FRONT EXTENDS FROM 31N65W THE CENTRAL BAHAMAS WHERE IT IS DISSIPATING. SOME SHOWERS AND ISOLATED TSTMS ARE NOTED ALONG THE FRONTAL BOUNDARY. TO THE EAST OF THE SECOND FRONT... THERE IS A RIDGE COVERING THE CENTRAL ATLC AND EXTENDING SW AND W TO THE NE CARIBBEAN AND THE SE BAHAMAS RESPECTIVELY. THE RIDGE IS CENTERED AROUND A 1028 MB HIGH NEAR 35N44W. THE STRONG PRESSURE GRADIENT BETWEEN THE RIDGE AND AN OCCLUDED LOW PRESSURE SYSTEM LOCATED NEAR 27N32W IS SUPPORTING GALE FORCE WINDS WITHIN AROUND 320 NM NW QUADRANT OF LOW CENTER. THE 1138 UTC ASCAT PASS CORROBORATED THESE WINDS SPEEDS. SCATTERED SHOWERS/POSSIBLE ISOLATED THUNDERSTORMS ARE AHEAD OF THE LOW/OCCLUDED FRONT N OF 25N BETWEEN 20W-31W. ALOFT...AN UPPER LEVEL RIDGE EXTENDS FROM THE NRN LEEWARD ISLANDS TO BEYOND 32N54W SUPPORTING THE SURFACE RIDGE WHILE A SHARP UPPER LEVEL TROUGH ALONG 30W SUPPORTS THE LOW PRESSURE SYSTEM. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GR