000 AXNT20 KNHC 292341 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST TUE JAN 29 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 FROM THE AFRICAN COAST NEAR 06N11W TO 04N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 04N16W TO 01N30W TO 02N44W TO 01N51W. SCATTERED MODERATE CONVECTION IS FROM 02N-03N BETWEEN 35W-39W. ...DISCUSSION... GULF OF MEXICO... MUCH OF THE GULF THIS EVENING IS UNDER THE INFLUENCE OF AN UPPER LEVEL RIDGE WITH AXIS ALONG 86W. WATER VAPOR IMAGERY INDICATES VERY DRY AIR AND SUBSIDENCE ALOFT WHICH IS PROVIDING OVERALL CLEAR SKIES AND FAIR CONDITIONS AT THE SURFACE UNDER SOUTHERLY WINDS IN THE RANGE OF 15 TO 25 KT. TO THE WEST OF THE UPPER LEVEL RIDGE...A VIGOROUS MIDDLE TO UPPER LEVEL TROUGH IS PROGRESSING OVER WESTERN TEXAS THIS EVENING AND CONTINUES TO DEVELOP AN AREA OF SURFACE LOW PRESSURE OVER NORTH TEXAS AND OKLAHOMA. THE ASSOCIATED COLD FRONT IS ANALYZED OVER THIS REGION AND IS EXPECTED TO EMERGE INTO THE NW GULF WATERS BY EARLY WEDNESDAY. IN THE MEANTIME...SOUTHERLY WINDS ARE EXPECTED TO INCREASE AHEAD OF THE FRONT ACROSS THE BASIN THROUGH WEDNESDAY AFTERNOON...WITH NORTHERLY WINDS USHERED IN WEST OF THE FRONT SPREADING ACROSS THE ENTIRE BASIN BY EARLY THURSDAY. HIGH PRESSURE WILL THEN BE IN CONTROL FRIDAY AND THROUGH THE WEEKEND. CARIBBEAN SEA... SOUTH-SOUTHWESTERLY FLOW ALOFT DOMINATES OVER THE CARIBBEAN SEA THIS EVENING AS WATER VAPOR IMAGERY INDICATES A VERY DRY AND SUBSIDENT ATMOSPHERE IS IN PLACE DUE TO A MID-LEVEL RIDGE ANCHORED OVER THE BASIN NEAR 15N80W. WHILE THE MIDDLE TO UPPER LEVELS ARE PROVIDING FAIRLY BENIGN WEATHER...AT THE SURFACE THE TRADE WINDS REMAIN IN THE RANGE OF 15 TO 25 KT...WITH HIGHER WINDS UP TO 30 KT POSSIBLE IN CLOSE PROXIMITY TO THE COAST OF COLOMBIA...DUE TO A STRONG PRESSURE GRADIENT BETWEEN SURFACE RIDGING OVER THE SW NORTH ATLC REGION AND LOWER PRESSURE LOCATED OVER THE NORTHERN SOUTH AMERICAN CONTINENT. ISOLATED SHOWERS ARE NOTED ON SATELLITE IMAGERY ACROSS THE BASIN THIS EVENING...WITH THE MOST CONCENTRATED AREAS N OF 14N BETWEEN 63W-73W...INCLUDING PUERTO RICO AND HISPANIOLA...AND ACROSS PORTIONS OF THE NW CARIBBEAN FROM 14N-18N BETWEEN 80W-88W. OVERALL LITTLE CHANGE IS EXPECTED SYNOPICALLY OVER THE NEXT 24 TO 36 HOURS. THEREAFTER... A COLD FRONT IS EXPECTED TO ENTER THE NW CARIBBEAN WATERS ON THURSDAY. ATLANTIC OCEAN... SURFACE HIGH PRESSURE IS CONTROLLING THE SW NORTH ATLC ANCHORED BY A 1025 MB HIGH CENTERED NEAR 30N71W. THE HIGH IS SUPPORTED BY A MIDDLE TO UPPER LEVEL RIDGE COVERING THE EASTERN CONUS AND EASTERN U.S. SEABOARD. EAST OF THE RIDGING...BROAD UPPER LEVEL TROUGHING IS NOTED ON WATER VAPOR IMAGERY N OF 26N BETWEEN 30W-60W THAT SUPPORTS A COLD FRONT ENTERING THE DISCUSSION AREA IN THE CENTRAL ATLC NEAR 32N29W. THE FRONT CONTINUES SW ALONG 24N40W TO 20N55W THEN WESTWARD TO 21N70W AS A COLD FRONT THAT CONTINUES TO DISSIPATE AND BECOME DIFFUSE. WIDELY SCATTERED SHOWERS ARE OCCURRING WITHIN 150 NM EAST OF THE FRONT E OF 39W AND WITHIN 210 NM W OF THE FRONT E OF 60W. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1030 MB HIGH CENTERED OVER THE IBERIAN PENINSULA NEAR 40N03W. THE RIDGE AXIS EXTENDS SW FROM THE HIGH TO 23N35W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN