000 AXNT20 KNHC 010526 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SUN MAR 01 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 5N7W 2N11W CROSSING THE EQUATOR NEAR 16W EXTENDING TO 1S31W INTO NE BRAZIL NEAR 3S45W. SCATTERED MODERATE CONVECTION IS S OF 2N BETWEEN 7W-13W. SCATTERED MODERATE CONVECTION IS ALSO S OF 3N BETWEEN 15W-24W. SIMILAR CONVECTION IS S OF 1N BETWEEN 26W-31W. ...DISCUSSION... GULF OF MEXICO... A DEEP LAYER TROUGH OVER THE E CONUS EXTENDS SOUTHWARD INTO THE GULF REGION. THIS DEEP LAYER TROUGH IS ASSOCIATED WITH A SURFACE COLD FRONT THAT EXTENDS FROM THE W FLORIDA PANHANDLE NEAR 30N87W TO 25N94W TO THE MEXICO COAST NEAR 21N97W AND A SURFACE TROUGH THAT EXTENDS FROM 29N87W TO 27N89W TO 26N92W. LOW LEVEL CONVERGENCE IN THE VICINITY OF THIS SURFACE FRONT AND SURFACE TROUGH IS SUPPORTING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ALONG AND WITHIN 60 NM E OF THE SURFACE COLD FRONT. IN THE WAKE OF THE COLD FRONT...INCREASED NORTHERLY WINDS ARE OCCURRING OVER THE GULF...WITH A GALE WARNING IN EFFECT FOR PORTIONS OF THE SW...MIDDLE...AND E GULF. ALSO...RELATIVELY COOLER AND DRIER CONDITIONS ARE PRESENT TO THE N OF THE FRONT. ACROSS MUCH OF THE SE GULF...DEEP LAYER DRY AIR IS RESULTING IN GENERALLY FAIR WEATHER CONDITIONS. THE COLD FRONT IS FORECAST TO MOVE E OF THE GULF REGION SUNDAY NIGHT. ADDITIONALLY...STRONG N TO NE SURFACE WINDS ARE FORECAST TO BLOW THROUGH THE ISTHMUS OF TEHUANTEPEC RESULTING IN GALE FORCE WINDS IN THE E PACIFIC REGION BEGINNING AT 01/1200 UTC AND STORM FORCE WINDS IN THE E PACIFIC REGION BEGINNING AT 02/0000 UTC. CARIBBEAN SEA... GENERALLY FAIR WEATHER CONDITIONS ARE OCCURRING ACROSS MUCH OF THE CARIBBEAN REGION...WHERE SUBSIDENCE IS BEING SUPPORTED BY CONFLUENCE IN WESTERLY FLOW ALOFT. PATCHES OF LOW LEVEL MOISTURE CONTINUE TO BE ADVECTED WESTWARD ACROSS THE CARIBBEAN...WITH SCATTERED SHOWERS EMBEDDED WITHIN THESE PATCHES OF LOW LEVEL MOISTURE. THE GREATEST CONCENTRATION OF THESE SHOWERS IS FROM 17N-21N BETWEEN 81W-86W. ALSO...INCREASED UPPER LEVEL MOISTURE IS STREAMING NORTHEASTWARD ACROSS PORTIONS OF THE E CARIBBEAN. THE AFOREMENTIONED COLD FRONT CURRENTLY OVER THE GULF OF MEXICO IS FORECAST TO MOVE INTO THE NW CARIBBEAN ON SUNDAY...WITH RELATIVELY COOLER AND DRIER CONDITIONS IN THE WAKE OF THE FRONT. ATLANTIC OCEAN... A DEEP LAYER TROUGH OVER THE E CONUS IS ASSOCIATED WITH THE AFOREMENTIONED SURFACE COLD FRONT OVER THE GULF OF MEXICO. THIS COLD FRONT EXTENDS NORTHEASTWARD INTO THE SE CONUS...AND IS FORECAST TO ENTER THE FAR NW WATERS OF THE SW NORTH ATLC SUNDAY MORNING. RELATIVELY COOLER AND DRIER CONDITIONS ARE PRESENT IN THE WAKE OF THE FRONT. FARTHER TO THE E...A DEEP LAYER TROUGH OVER THE CENTRAL ATLC IS ASSOCIATED WITH A SURFACE TROUGH OVER THE CENTRAL ATLC THAT EXTENDS FROM 21N62W TO 24N61W TO 27N58W...A SURFACE TROUGH ALSO OVER THE CENTRAL ATLC THAT EXTENDS FROM 27N58W TO 30N44W TO 31N32W...AND A SURFACE COLD FRONT ALSO OVER THE CENTRAL ATLC THAT EXTENDS FROM 31N32W TO 32N25W TO NE OF THE DISCUSSION AREA. LOW LEVEL CONVERGENCE IS SUPPORTING SCATTERED SHOWERS WITHIN 120 NM EITHER SIDE OF THE SURFACE FRONTS AND SURFACE TROUGH. THIS ACTIVITY IS BEING ENHANCED BY ATMOSPHERIC LIFT ASSOCIATED WITH UPPER LEVEL DIVERGENCE IN THE SW QUADRANT OF A 90-100 KT UPPER LEVEL JET MAXIMUM OVER THE CENTRAL ATLC. COMPUTER MODEL GUIDANCE SUGGESTS THAT THIS AREA OF ATMOSPHERIC LIFT IS EXPECTED TO INTERACT WITH THE SURFACE FRONTS OVER THE CENTRAL ATLC TO RESULT IN THE DEVELOPMENT OF A SURFACE LOW OVER THE CENTRAL ATLC DURING THE NEXT DAY...WHICH IS EXPECTED TO BE A 1017 MB SURFACE LOW NEAR 31N44W AT 02/0000 UTC. ALSO...ACROSS LOCATIONS IN THE CENTRAL AND E ATLC THAT ARE SE OF THE SURFACE FRONTS AND SURFACE TROUGH...SUBSIDENCE ASSOCIATED WITH A SURFACE RIDGE IS SUPPORTING FAIR WEATHER CONDITIONS. THIS SURFACE RIDGE EXTENDS SOUTHWARD FROM A 1025 MB SURFACE HIGH NEAR 29N35W. THIS SURFACE HIGH IS FORECAST TO BE POSITIONED NEAR 29N35W AS A 1025 MB SURFACE HIGH AT 02/0000 UTC. ACROSS THE TROPICAL ATLC...AN UPPER LEVEL RIDGE IS S OF 13N E OF 58W WITH AN UPPER LEVEL HIGH NEAR 2N24W. UPPER LEVEL DIVERGENCE ASSOCIATED WITH THIS UPPER LEVEL RIDGE AND UPPER LEVEL HIGH IS ENHANCING THE CONVECTION ASSOCIATED WITH THE ITCZ. $$ COHEN