AXNT20 KNHC 082347 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST THU JAN 08 2009 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...THE ITCZ... ITCZ IS CENTERED ALONG 7N10W CROSSING THE EQUATOR AT 28W AND INTO NE BRAZIL NEAR 3S42W. CLUSTERS OF MODERATE CONVECTION ARE FROM 8S-2N BETWEEN 25W-33W. ELSEWHERE...SCATTERED MODERATE CONVECTION IS INLAND AND WITHIN 60 NM OF THE NE BRAZIL COAST BETWEEN 41W-51W. ...DISCUSSION... GULF OF MEXICO... A RELATIVELY COOLER AND DRIER AIR MASS IS POSITIONED ACROSS THE GULF AS A 1017 MB SURFACE HIGH PRESSURE IS CENTERED NEAR 27N91W. MULTILEVEL CLOUDS REMAIN OVER THE YUCATAN CHANNEL AND FLORIDA STRAITS WHILE DRY AIR IN STRONG SUBSIDENCE IS LOCATED ELSEWHERE IN THE MID/UPPER LEVELS OVER THE GULF. THE SURFACE HIGH IS EXPECTED TO WEAKEN AND SHIFT NE DURING THE NEXT 24 HOURS. EXPECT THE NEXT COLD FRONT TO MOVE OFF THE UPPER TEXAS COAST EARLY SAT. CARIBBEAN SEA... AS OF 2100 UTC...A STATIONARY FRONT EXTENDS ACROSS CUBA ENTERING THE NW CARIBBEAN NEAR 22N81W AND CONTINUING SW TO THE CENTRAL BELIZE COAST NEAR 17N88W. THIS FRONT IS EXPECTED TO WEAKEN OVER THE NEXT 6-12 HOURS. IN THE MEANTIME...POSSIBLE ISOLATED SHOWERS ARE LOCATED WITHIN 60 NM OF THE FRONT. EASTERLY WINDS OF 10 TO 20 KT ARE OBSERVED ACROSS THE CARIBBEAN WITH AN AREA OF MAXIMUM WINDS WITHIN 90 NM OF THE COLOMBIA COAST. IN THE UPPER LEVELS... AN UPPER RIDGE IS CENTERED ACROSS NRN COLOMBIA AND PROVIDES THE BASIN WITH DRY AIR IN SUBSIDENCE MAINLY E OF 82W. ATLANTIC OCEAN... A DEEP LAYER TROUGH IS OVER THE ERN U.S. SEABOARD AND SUPPORTS A COLD FRONT IN THE W ATLC THAT ENTERS THE DISCUSSION AREA NEAR 32N65W AND CONTINUES SW ACROSS THE CENTRAL BAHAMAS TO CUBA NEAR 23N80W. SCATTERED SHOWERS AND POSSIBLE TSTMS ARE WITHIN 60 NM OF THE FRONT. AS THE BOUNDARY PROGRESSES EWD DURING THE NEXT 24 HOURS IT IS FORECAST TO GRADUALLY DISSIPATE BY LATE SAT. THE REST OF THE ATLC IS DOMINATED BY A RIDGE ANCHORED ON A 1026 MB SURFACE HIGH CENTERED NEAR 30N40W. FAIR WEATHER STRATOCUMULUS CLOUDS FLOW AROUND THE SRN PERIPHERY OF THE RIDGE. ALOFT... INSTABILITY AND UPPER DIFFLUENCE AROUND AN UPPER LOW NEAR 20N46W IS GENERATING A SMALL CLUSTER OF MODERATE SHOWERS FROM 10N-18N BETWEEN 32W-50W. $$ HUFFMAN
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