000 AXNT20 KNHC 242339 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST THU JAN 24 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 7N12W CONTINUING TO 6N16W WHERE THE ITCZ CONTINUES ALONG 3N23W ACROSS THE EQUATOR NEAR 33W. CLUSTERS OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION ARE FROM 3N TO S OF THE EQUATOR BETWEEN 31W-49W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE EXTENDS FROM MEXICO TO OVER THE CENTRAL PLAIN STATES INCLUDING THE W GULF OF MEXICO. A BROAD UPPER TROUGH OVER THE W ATLC NARROWS SIGNIFICANTLY AS IT ENTERS THE SE GULF NEAR THE FLORIDA KEYS CONTINUING TO THE E BAY OF CAMPECHE. WATER VAPOR IMAGERY INDICATES THAT STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT COVERS THE GULF N OF THE UPPER TROUGH WITH INCREASED INSTABILITY AND LIFTING DYNAMICS OVER THE EXTREME SE GULF WITH ISOLATED SHOWERS S OF A LINE FROM 24N80W TO 22N88W... INCLUDING CUBA...THE YUCATAN CHANNEL...AND PORTIONS OF THE YUCATAN PENINSULA. A SURFACE RIDGE COVERS THE GULF ANCHORED BY A 1028 MB HIGH OVER THE MISSISSIPPI DELTA OF LOUISIANA GIVING THE REMAINDER OF THE GULF MOSTLY CLEAR SKIES THIS EVENING. HIGH PRESSURE WILL DOMINATE THE GULF THROUGH SAT WHEN A COLD FRONT WILL CLIP THE NE GULF SAT NIGHT AND STALL OVER THE SAME AREA SUN. HIGH PRESSURE WILL MOVE NE OF THE AREA SUN WITH INCREASING E TO SE WINDS OVER THE ENTIRE GULF SUN THROUGH TUE. CARIBBEAN SEA... THE NARROW UPPER TROUGH OVER THE SE GULF OF MEXICO COUPLED WITH A BROAD UPPER RIDGE OVER THE CENTRAL ATLC IS GIVING THE CARIBBEAN SW FLOW ALOFT. WATER VAPOR IMAGERY INDICATES THAT STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT COVERS ALL BUT THE NW CARIBBEAN WITH INCREASED INSTABILITY AND ISOLATED SHOWERS ARE NW OF A LINE CENTRAL CUBA NEAR SANTA CLARA TO HONDURAS NEAR 16N85W...INCLUDING THE YUCATAN CHANNEL AND PORTIONS OF THE YUCATAN PENINSULA. FRESH TO STRONG TRADE WINDS ARE ACROSS THE CENTRAL CARIBBEAN AND ARE USHERING IN SOME POSSIBLE ISOLATED SHOWERS ACROSS THE AREA E OF 83W. THE TRADE WINDS WILL PERSIST THROUGH MON. ATLANTIC OCEAN... A BROAD UPPER TROUGH COVERS THE AREA N OF 30N W OF 55W TO OVER THE NE CONUS NARROWING ACROSS THE W ATLC S OF 30N TO BETWEEN 65W-80W WITH A VERY NARROW EXTENSION CONTINUING INTO THE SE GULF OF MEXICO. THIS BROAD UPPER TROUGH IS SUPPORTING A COLD FRONT THAT REMAINS N OF THE DISCUSSION AREA. A REMNANT STATIONARY FRONT REMAINS ACROSS THE CENTRAL ATLC ENTERING THE DISCUSSION AREA NEAR 32N51W CONTINUING ALONG 27N60W TO 22N69W WITH A SHEAR AXIS ANALYZED TO OVER HAITI NEAR 18N73W. SCATTERED SHOWERS ARE POSSIBLE WITHIN 90 NM EITHER SIDE OF THIS FRONT. A SURFACE RIDGE IS BEING SQUEEZED BETWEEN THE REMNANT STATIONARY FRONT AND THE APPROACHING COLD FRONT GIVING THE REMAINDER OF THE W ATLC FAIR WEATHER THIS EVENING. A BROAD UPPER RIDGE EXTENDS FROM THE W TROPICAL ATLC NEAR 15N50W TO BEYOND 32N36W WITH A NARROWING UPPER TROUGH EXTENDING FROM OVER AFRICA AND S MOROCCO/N WESTERN SAHARA ALONG 20N24W TO A BASE NEAR 12N40W. A SURFACE RIDGE DOMINATES THE E ATLC E OF THE ABOVE STATIONARY FRONT ANCHORED BY A 1031 MB HIGH NEAR 32N25W GIVING THE REMAINDER OF THE ATLC FAIR WEATHER THIS EVENING. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW