000 AXNT20 KNHC 161744 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST SUN JAN 16 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... ITCZ AXIS IS ANALYZED ALONG 6N9W 3N17W THEN ALONG THE EQUATOR BETWEEN 27W39W THEN S INTO BRAZIL. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS S OF 1N ACROSS THE EQUATOR BETWEEN 31W-45W. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE COVERS THE GULF EXTENDING FROM THE CARIBBEAN WITH A SWATH OF MODERATE SUBSIDENCE AND DRY STABLE AIR ALOFT WITHIN 120/150 NM OF LINE FROM ACROSS FLORIDA NEAR TAMPA TO OVER MEXICO NEAR TUXPAN. A WEAK SURFACE TROUGH DENOTING A WIND SHIFT IS ALSO ACROSS THE FLORIDA PENINSULA FROM MELBOURNE TO FORT MYERS INTO THE GULF TO 26N84W. A SURFACE RIDGE IS NW OF THE SURFACE TROUGH ANCHORED BY A 1022 MB HIGH OFF THE COAST OF ALABAMA/MISSISSIPPI NEAR 30N88W AND A 1023 MB HIGH OVER NE ALABAMA. AN UPPER TROUGH IS INLAND OVER TEXAS AND N MEXICO MOVING TOWARD THE FAR NW GULF WITH A FRONTAL SYSTEM INLAND AS WELL. HOWEVER...SCATTERED/HEAVY SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE OVER THE NW GULF W OF A LINE FROM VERMILION BAY LOUISIANA TO OFF THE COAST OF MEXICO NEAR 23N95W. SCATTERED/BROKEN LOW CLOUDS WITH POSSIBLE ISOLATED SHOWERS DOT MUCH OF THE REMAINDER OF THE GULF. THE SURFACE RIDGE IS EXPECTED TO SHIFT NE AND EXIT THE GULF TONIGHT AS LOWER PRESSURE ACCOMPANIED BY FRONTAL BOUNDARIES MOVE THROUGH THE GULF THROUGH WED. CARIBBEAN SEA... BROAD UPPER RIDGE DOMINATES THE CARIBBEAN ANCHORED IN THE W TROPICAL ATLC WITH STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT. MODERATE TRADE WINDS ARE ACROSS THE E AND CENTRAL CARIBBEAN BANKING LOW/MID CLOUDS WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE W CARIBBEAN MAINLY FROM 12N-17N BETWEEN 80W-84W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS S OF 22N W OF 84W TO INLAND OVER HONDURAS AND THE YUCATAN PENINSULA. EXPECT THE TRADES TO INCREASE ACROSS THE CENTRAL AND E CARIBBEAN BY MON THROUGH WED. ATLANTIC OCEAN... BROAD UPPER RIDGE THAT DOMINATES THE CARIBBEAN COVERS THE W AND CENTRAL ATLC TO 30W WITH MODERATE/STRONG SUBSIDENCE MOSTLY S OF 24N. A WEAK SURFACE TROUGH DENOTING A WIND SHIFT EXTENDS FROM 30N77W ACROSS THE FLORIDA PENINSULA NEAR MELBOURNE. AN UPPER TROUGH OVER THE NE ATLC EXTENDS S TO ALONG THE COAST OF W AFRICA AND IS SUPPORTING A STATIONARY BOUNDARY THAT EXTENDS W ACROSS THE CENTRAL ATLC THROUGH 32N30W 28N50W TO 26N60W WHERE IT RETREATS N AS A WARM FRONT ALONG 26N66W TO 24N72W CONTINUING SW OVER THE BAHAMAS TO NEAR 22N75W. THE BROAD UPPER RIDGE ACROSS THE W AND CENTRAL ATLC IS ENHANCING SCATTERED SHOWERS MAINLY N OF FRONT TO 30N BETWEEN 50W-70W AND FROM 28N-32N BETWEEN 20W-40W. A SURFACE RIDGE COVERS THE E AND CENTRAL ATLC...SPLIT BY THE FRONT...WITH A 1024 MB HIGH N OF THE FRONT NEAR 31N51W AND A 1025 MB HIGH SE OF THE FRONT NEAR 28N31W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW