000 AXNT20 KNHC 211749 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN MAR 21 2010 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC... ...ITCZ... ITCZ AXIS IS CENTERED ALONG 7N11W 4N16W 2N29W CROSSING THE EQUATOR NEAR 39W AND INTO NE BRAZIL NEAR 2S43W. SCATTERED MODERATE CONVECTION IS FROM 2N-9N BETWEEN 10W-19W. ISOLATED MODERATE CONVECTION IS FROM THE EQUATOR TO 5N BETWEEN 26W-35W. ...DISCUSSION... GULF OF MEXICO... AS OF 1500 UTC...A COLD FRONT ENTERS THE NE GULF FROM THE FLORIDA PANHANDLE NEAR 30N87W AND CONTINUES S-SW ALONG 27N86W TO THE YUCATAN PENINSULA NEAR 22N88W AND INLAND ALONG THE SOUTHERN MEXICO GULF COAST. MOSAIC DOPPLER RADAR IMAGERY AND LIGHTNING DATA INDICATES A STRONG LINE OF SCATTERED TSTMS EXTENDING FROM JUST NORTH OF THE TAMPA BAY AREA SW TO THE FRONT NEAR 26N85W. NUMEROUS SHOWERS FOLLOW WEST OF THE INITIAL LINE TO THE COLD FRONT ACROSS THE NE GULF N OF 25N...INCLUDING INLAND PORTIONS OF THE NORTHERN FLORIDA PENINSULA. ISOLATED SHOWERS ARE ALSO WITHIN 90 NM EITHER SIDE OF THE COLD FRONT S OF 25N AND OVER SOUTHERN MEXICO...INCLUDING THE YUCATAN PENINSULA. WEST TO NORTHWEST SURFACE WINDS TO GALE FORCE ARE OCCURRING OVER THE NORTHERN GULF WEST OF THE FRONT AND ARE FORECAST TO DIMINISH BY LATE SUNDAY AS A SURFACE RIDGE ANCHORED BY A 1029 MB HIGH CENTERED OVER NE MEXICO CONTINUES TO SETTLE SE OVER THE WESTERN GULF THROUGH MONDAY. THE AFOREMENTIONED COLD FRONT IS SUPPORTED ALOFT BY A VIGOROUS UPPER LEVEL SHORTWAVE TROUGH PROGRESSING ACROSS THE LOWER MISSISSIPPI RIVER VALLEY WITH UPPER LEVEL DIFFLUENCE LOCATED EAST OF THE TROUGH AXIS ALONG 94W. THE UPPER LEVEL SUPPORT CONTINUES TO ENHANCE THE CONVECTION ASSOCIATED WITH THE COLD FRONT AS IT MOVES EASTWARD THIS AFTERNOON. CARIBBEAN SEA... FRESH TO STRONG TRADEWINDS DOMINATE A MAJORITY OF THE EASTERN AND CENTRAL CARIBBEAN THIS AFTERNOON. LOW-LEVEL SPEED CONVERGENCE OF THESE TRADEWINDS ARE GENERATING A FEW ISOLATED SHOWERS OVER THE WESTERN CARIBBEAN WITHIN 200 NM EITHER SIDE OF A LINE FROM 9N-17N ALONG 82W...INCLUDING COASTAL AREAS OF WESTERN PANAMA...COSTA RICA...AND INLAND AREAS OF NICARAGUA AND FAR EASTERN HONDURAS. A COLD FRONT IS FORECAST TO PROGRESS INTO THE NW CARIBBEAN LATER THIS AFTERNOON BRINGING AN INCREASED CHANCE FOR SCATTERED SHOWERS AND POSSIBLE ISOLATED TSTMS ACROSS THE YUCATAN CHANNEL AND WESTERN CUBA. ALOFT...MUCH OF THE CARIBBEAN IS UNDER THE INFLUENCE OF A BROAD UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED IN THE WESTERN CARIBBEAN NEAR 13N76W. THE UPPER LEVEL HIGH EXTENDS A RIDGE AXIS W-SW INTO THE EASTERN PACIFIC REGION AS WELL AS E-NE ACROSS THE LESSER ANTILLES AND INTO THE TROPICAL NORTH ATLC WITH GENERALLY DRY AIR AND OVERALL STABLE ATMOSPHERIC CONDITIONS PREVAILING. ATLANTIC OCEAN... A BROAD UPPER LEVEL RIDGE DOMINATES MOST OF THE W ATLC WITH THE AXIS EXTENDING FROM THE CARIBBEAN ACROSS HISPANIOLA TO BEYOND BERMUDA NEAR 32N65W. HOWEVER...AT THE SURFACE...AS THE COLD FRONT ACROSS THE EASTERN GULF OF MEXICO APPROACHES THE FLORIDA PENINSULA...SCATTERED SHOWERS ARE OCCURRING N OF 27N W OF 78W. FARTHER EAST...A COLD FRONT ENTERS THE CENTRAL ATLC NEAR 32N41W AND EXTENDS SW TO 25N52W BECOMING STATIONARY TO NEAR 22N68W. ISOLATED SHOWERS ARE WITHIN 120 NM EITHER SIDE OF THE COLD FRONT OVER THE CENTRAL ATLC...WHILE REMAINING MAINLY WITHIN 200 NM NORTH OF THE STATIONARY BOUNDARY TRAILING ACROSS THE SW NORTH ATLC. THIS FRONT IS SUPPORTED BY AN UPPER LEVEL SHORTWAVE TROUGH WITH AXIS ALONG 37N43W TO 29N53W. THE REMAINDER OF THE EASTERN ATLC IS DOMINATED BY A SURFACE RIDGE WITH AXIS EXTENDING FROM A 1027 MB HIGH CENTERED NEAR 34N23W SW TO 20N50W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN