000 AXNT20 KNHC 101131 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST SAT JAN 10 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...THE ITCZ... ITCZ IS CENTERED ALONG 8N12W 5N20W 2N28W 1N33W AND INTO NE BRAZIL NEAR 3S45W. SCATTERED MODERATE CONVECTION IS FROM 2N-4N BETWEEN 14W-19W. SCATTERED MODERATE CONVECTION IS ALSO FROM 1N-4N BETWEEN 22W-26W. ...DISCUSSION... GULF OF MEXICO... WESTERLY FLOW ALOFT IS PRESENT ACROSS THE GULF REGION...WHERE DEEP LAYER DRY AIR AND SUBSIDENCE ARE RESULTING IN GENERALLY FAIR WEATHER CONDITIONS. THE RETURN FLOW AROUND A 1027 MB SURFACE HIGH SE OF NORTH CAROLINA NEAR 34N76W IS BRINGING SOUTHERLY WINDS OF 10 TO 20 KT ACROSS MUCH OF THE GULF REGION. INCREASING WARM AIR ADVECTION RESULTING FROM THIS SOUTHERLY FLOW IS CAUSING A SURFACE WARM FRONT TO DEVELOP...WHICH EXTENDS FROM 24N86W TO 27N88W TO S LOUISIANA NEAR 29N91W. LOW LEVEL CONVERGENCE NEAR THIS FRONT IS RESULTING IN SCATTERED SHOWERS N OF 24N BETWEEN 87W-91W. FARTHER TO THE NORTH...A DEEP LAYER TROUGH OVER THE W CONUS IS MOVING EASTWARD...WITH AN ASSOCIATED SURFACE FRONT EXTENDING FROM THE SOUTHERN PLAINS OF THE CONUS INTO NORTH MEXICO. THIS FRONT IS FORECAST TO MOVE SOUTHWARD ACROSS THE GULF THIS WEEKEND INTO EARLY NEXT WEEK. INCREASED N WINDS AND COOLER CONDITIONS ARE FORECAST IN THE WAKE OF THIS FRONT...WITH GALE CONDITIONS EXPECTED ACROSS PORTIONS OF THE SW GULF FOR SUNDAY THROUGH MONDAY. CARIBBEAN SEA... AN UPPER RIDGE IS PRESENT ACROSS THE CARIBBEAN REGION...WITH THE UPPER RIDGE AXIS EXTENDING FROM N VENEZUELA NEAR 10N67W TO 15N70W TO 18N71W. SUBSIDENCE AND STABLE ATMOSPHERIC CONDITIONS ASSOCIATED WITH THIS UPPER RIDGE ARE RESULTING IN GENERALLY FAIR WEATHER CONDITIONS ACROSS MUCH OF THE CARIBBEAN SEA. HOWEVER...ACROSS THE SW CARIBBEAN...DEEP MOISTURE IS BEING TRANSPORTED NORTHWARD TO THE W OF THE UPPER RIDGE AXIS...WHICH IS RESULTING IN SCATTERED SHOWERS S OF 11N BETWEEN 76W-79W. MODERATE TO FRESH TRADE WINDS ARE PRESENT ACROSS THE CARIBBEAN SEA. THESE TRADE WINDS ARE FORECAST TO CONTINUE DURING THE NEXT FEW DAYS AS THE 1027 MB SURFACE HIGH SE OF NORTH CAROLINA NEAR 34N76W MOVES EASTWARD. THE STRONGEST WINDS...UP TO 30 KT...ARE NEAR THE COAST OF COLOMBIA. ATLANTIC OCEAN... A DEEP TROUGH IS PRESENT ACROSS THE W ATLC N OF THE DISCUSSION AREA...WHICH IS ASSOCIATED WITH A SURFACE COLD FRONT AND A SURFACE TROUGH. THE SURFACE COLD FRONT EXTENDS FROM 22N72W TO 26N61W TO 32N51W TO NE OF THE DISCUSSION AREA...WITH LOW LEVEL CONVERGENCE SUPPORTING SCATTERED SHOWERS WITHIN 90 NM EITHER SIDE OF THIS FRONT. THE SURFACE TROUGH EXTENDS FROM 26N75W TO 28N63W TO 32N56W TO NE OF THE DISCUSSION AREA...WITH LOW LEVEL CONVERGENCE SUPPORTING ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THIS SURFACE TROUGH. TO THE W OF THE SURFACE TROUGH...DEEP LAYER DRY AIR AND SUBSIDENCE ARE RESULTING IN GENERALLY FAIR WEATHER ACROSS MUCH OF THE SW ATLC. THE SUBSIDENCE IS BEING ENHANCED AROUND THE 1027 MB SURFACE HIGH SE OF NORTH CAROLINA NEAR 34N76W. FARTHER TO THE E...A 1026 MB SURFACE HIGH IS PRESENT NEAR 30N38W. SUBSIDENCE ASSOCIATED WITH THIS SURFACE HIGH IS RESULTING IN FAIR WEATHER ACROSS MUCH OF THE E ATLC. HOWEVER...AN UPPER TROUGH EXTENDS FROM 25N33W TO AN UPPER LOW NEAR 20N42W TO 13N45W. ATMOSPHERIC INSTABILITY ASSOCIATED WITH THIS UPPER LOW AND UPPER TROUGH IS RESULTING IN SCATTERED SHOWERS FROM 11N-17N BETWEEN 31W-37W. THIS ACTIVITY IS BEING ENHANCED BY UPPER LEVEL DIVERGENCE IN THE NE QUADRANT OF AN UPPER LEVEL JET MAXIMUM LOCATED SE OF THE UPPER LOW. ALSO...A SURFACE TROUGH EXTENDS FROM 30N10W TO A 1014 MB SURFACE LOW NEAR 28N12W TO 26N16W. DEEP LAYER DRY AIR IS INHIBITING DEEP CONVECTION NEAR THE SURFACE LOW AND THE SURFACE TROUGH. ACROSS THE TROPICAL ATLC...AN UPPER RIDGE AXIS EXTENDS FROM 6N10W TO 5N25W TO 3N33W. UPPER LEVEL DIVERGENCE NEAR THIS UPPER RIDGE IS ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ. $$ COHEN