000 AXNT20 KNHC 100548 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST TUE JAN 10 2012 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N12W TO 06N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N16W TO 02N26W TO THE EQUATOR NEAR 47W. NO SIGNIFICANT CONVECTION NOTED ON SATELLITE IMAGERY. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL RIDGING IS OVER THE GULF THIS EVENING AHEAD OF AN APPROACHING UPPER LEVEL LOW AND ASSOCIATED TROUGH CENTERED OVER WEST TEXAS. PER PREVIOUS DISCUSSIONS THE LAST FEW NIGHTS...THIS UPPER LEVEL TROUGH HAS INDUCED CYCLOGENESIS ALONG THE TEXAS GULF COAST WITH A 1010 MB LOW CENTERED IN THE VICINITY OF GALVESTON BAY NEAR 29N95W AND A COLD FRONT EXTENDING SOUTH-SOUTHWEST FROM THE LOW TO THE MEXICO COAST NEAR 24N98W. MOSAIC DOPPLER RADAR IMAGERY AND LIGHTNING DATA INDICATE THAT NUMEROUS SHOWERS AND SCATTERED TSTMS ARE OCCURRING FROM 27N-31N BETWEEN 89W-95W... INCLUDING INTERIOR PORTIONS OF LOUISIANA AND SW MISSISSIPPI. WITH THE COLD FRONT ENTERING INTO THE NW GULF WATERS...N-NW WINDS IN THE RANGE OF 20 TO 30 KT ARE EXPECTED THROUGH THE OVERNIGHT PERIOD WEST OF THE FRONT. EAST OF THE FRONT...THE REMAINDER OF THE GULF IS UNDER THE INFLUENCE OF AN EASTWARD RETREATING RIDGE WHICH IS PROVIDING SE WINDS...CLEAR SKIES...AND GENERALLY FAIR CONDITIONS. THE FRONT IS EXPECTED TO MOVE EAST OF THE BASIN BY LATE WEDNESDAY AS WEAK HIGH PRESSURE SETTLES INTO THE GULF ONCE AGAIN WITH THE NEXT COLD FRONT ON THE DOOR STEP OF THE NW GULF WATERS FORECAST TO EMERGE OFF THE TEXAS COAST EARLY THURSDAY. CARIBBEAN SEA... AN UPPER LEVEL RIDGE AXIS EXTENDS FROM THE TROPICAL NORTH ATLC NEAR 07N55W NW TO OVER THE YUCATAN CHANNEL NEAR 21N84W. WATER VAPOR IMAGERY INDICATES MOSTLY DRY AIR AND SUBSIDENCE IS LOCATED N OF 10N AND IS PROVIDING AN OVERALL STABLE ATMOSPHERE ACROSS THE CARIBBEAN THIS EVENING. SHORTWAVE INFRARED SATELLITE IMAGERY SHOWS TRANQUIL CONDITIONS PERSIST WITH E-NE TRADES IN THE RANGE OF 10 TO 20 KT...WITH HIGHER WINDS EXPECTED IN THE VICINITY OF THE COAST OF COLOMBIA. POSSIBLE ISOLATED LOW-TOPPED SHOWERS ARE LOCATED ACROSS INTERIOR PORTIONS OF HISPANIOLA AND THE ADJACENT COASTAL WATERS...AND OVER THE SE CARIBBEAN S OF 12N BETWEEN 60W-67W. ATLANTIC OCEAN... THE UPPER LEVEL PATTERN ACROSS THE WESTERN AND CENTRAL ATLC REMAINS RATHER BENIGN WITH WEST-NORTHWESTERLY FLOW DOMINATING AND KEEPING MUCH OF THE REGION W OF 45W UNDER MOSTLY FAIR CONDITIONS. AT THE SURFACE...THESE FAIR CONDITIONS ARE REINFORCED BY A SURFACE RIDGE EXTENDING EAST-WEST ALONG 29N/30N BETWEEN A 1021 MB HIGH CENTERED NEAR 30N52W AND A 1021 MB HIGH CENTERED NEAR 29N74W WHICH EXTENDS INFLUENCE WESTWARD ACROSS THE FLORIDA PENINSULA AND INTO THE NE GULF OF MEXICO. A SLIGHT WEAKNESS WITHIN THE RIDGE IS NOTED ON SATELLITE IMAGERY AS A SURFACE TROUGH IS ANALYZED FROM 22N65W TO EASTERN HISPANIOLA NEAR 19N72W WITH ISOLATED SHOWERS OCCURRING WITHIN 150 NM EITHER SIDE OF THE TROUGH AXIS. FARTHER EAST...WEAK UPPER LEVEL TROUGHING IS LOCATED N OF 20N BETWEEN 35W-50W AND SUPPORTS A 1012 MB SURFACE LOW CENTERED NEAR 32N40W AND A PAIR OF SURFACE TROUGHS...ONE EXTENDING S-SW FROM THE LOW CENTER TO 26N43W AND THE OTHER ANALYZED FROM 27N36W TO 19N41W. MOST OF THE WIDELY SCATTERED SHOWER ACTIVITY IS LOCATED EAST OF THE LOW CENTER N OF 30N BETWEEN 32W-39W...AND WITHIN 150 NM EITHER SIDE OF THE DETACHED SURFACE TROUGH TO THE SE. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE WITH AXIS EXTENDING FROM THE AZORES NEAR 38N27W SOUTHWARD TO 23N30W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN