000 AXNT20 KNHC 030533 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SUN MAR 03 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM NORTHERN GUINEA NEAR 11N15W INTO THE TROPICAL EAST ATLC ALONG 5N17W 3N21W. THE ITCZ CONTINUES FROM 3N21W TO 1N36W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM NORTH OF THE AXIS BETWEEN 23W-37W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL TROUGH OVER THE EASTERN CONUS AND GULF OF MEXICO EXTENDS FROM ALABAMA TO NORTHERN MEXICO CONTINUING TO ADVECT COOLER AIR ACROSS THE BASIN. DRY AIR ALOFT IS KEEPING THE WESTERN GULF WEST OF 93W WITH CLEAR SKIES...WHILE OVERCAST CONDITIONS AND POSSIBLE ISOLATED SHOWERS REMAIN OVER THE EASTERN PORTIONS OF THE AREA. A TIGHT PRESSURE GRADIENT BETWEEN HIGHER PRESSURE OVER TEXAS AND THE WESTERN GULF...AND LOWER PRESSURE ACROSS THE WEST ATLC CONTINUES TO SUPPORT STRONG NORTHWEST WINDS OF 20-25 KT. THE UPPER TROUGH IS EXPECTED TO MOVE EAST AND WILL ALLOW SURFACE RIDGING TO BUILD IN AND DOMINATE THE GULF. AS THE RIDGE BUILDS IN WIND SPEEDS WILL DECREASE BEFORE ANOTHER COLD FRONT MOVES IN THE AREA IN THE MIDDLE OF NEXT WEEK. CARIBBEAN SEA... AS OF 0300 UTC...A COLD FRONT EXTENDS THROUGH THE NW CARIBBEAN FROM EASTERN CUBA NEAR 21N75W TO COSTA RICA ALONG 18N81W 10N83W. STRONG NORTHERLY WINDS ARE BEHIND THE FRONT REACHING 20-25 KT IN MOST SPOTS WITH A SMALL AREA OF GALE FORCE WINDS OFF THE COAST OF HONDURAS FROM 15N-17N BETWEEN 82W-85W. OVERCAST SKIES AND ISOLATED SHOWERS ARE BOTH AHEAD AND BEHIND THE FRONT BETWEEN 75W-84W. THE EASTERN CARIBBEAN REMAINS UNDER CLEAR SKIES DUE TO DRY AIR ALOFT AROUND A BROAD UPPER LEVEL RIDGE WITH AXIS ALONG 55W. TRADEWIND FLOW OF 15-20 KT IS PRESENT OVER THIS AREA. EXPECT THE FRONT TO CONTINUE MOVING SLOWLY EAST. ISOLATED SHOWERS ARE LIKELY ACROSS MUCH OF THE CENTRAL CARIBBEAN AS THE FRONT MOVES EAST. ATLANTIC OCEAN... THE COLD FRONT IN THE CARIBBEAN IS ALSO IMPACTING A GOOD PORTION OF THE WEST AND CENTRAL ATLC. THE FRONT ENTERS THE DISCUSSION AREA NEAR 32N30W AND CONTINUES TO 26N55W WHERE IT BECOMES STATIONARY TO 26N69W BEFORE BECOMING COLD AGAIN TO THE CARIBBEAN NEAR 21N76W. ISOLATED SHOWERS ARE POSSIBLE NEAR THE FRONT AXIS ACROSS THE CENTRAL ATLC WITH ISOLATED TO SCATTERED SHOWERS COVERING A WIDE AREA IN THE WEST ATLC BETWEEN 68W-76W. THIS AREA IS LIKELY ENHANCED BY UPPER LEVEL DIFFLUENCE BETWEEN THE UPPER LEVEL TROUGH OVER THE EASTERN CONUS AND GULF OF MEXICO AND A BROAD UPPER LEVEL RIDGE COVERING THE WEST AND CENTRAL ATLC ALONG 55W. THE UPPER LEVEL TROUGH WILL CONTINUE TO PUSH THE WESTERN PORTIONS OF THE FRONT EASTWARD. THE UPPER RIDGE SUPPORTS A SURFACE RIDGE AROUND A PAIR OF HIGH CENTERS SOUTH OF THE FRONT IN THE CENTRAL ATLC. A 1018 MB HIGH IS NEAR 20N49W...WHILE A 1017 MB HIGH IS NEAR 20N25W. THE TWO HIGH CENTERS ARE KEEPING MUCH OF THE CENTRAL AND EASTERN TROPICAL ATLC UNDER FAIR CONDITIONS. AN UPPER LEVEL TROUGH IS OVER THE FAR EASTERN ATLC FROM THE AZORES ISLANDS TO NEAR THE CAPE VERDE ISLANDS BEFORE CHANGING DIRECTS WITH THE AXIS HEADING SOUTHWEST INTO THE TROPICAL ATLC ACROSS THE CAPE VERDE ISLANDS TO NEAR 9N45W. THE NORTHERN PORTION OF THE UPPER TROUGH SUPPORTS THE EASTERN PORTION OF THE COLD FRONT IN THE CENTRAL ATLC ALONG WITH SCATTERED SHOWERS NORTH OF 29N BETWEEN 15W-32W. THE UPPER TROUGH ALSO SUPPORTS A SURFACE TROUGH EXTENDING FROM NEAR 31N12W TO 21N19W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON