000 AXNT20 KNHC 200552 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST WED FEB 20 2008 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND THE 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... ITCZ AXIS IS CENTERED ALONG 8N12W 5N21W 3N34W CROSSING THE EQUATOR NEAR 47W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 3N-7N BETWEEN 9W-20W. SCATTERED MODERATE WITH EMBEDDED CLUSTERS OF ISOLATED STRONG CONVECTION ARE FROM 5N TO S OF THE EQUATOR BETWEEN 36W-53W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYERED TROUGH COVERS THE E HALF OF THE U.S. INTO THE GULF N OF 26N ACROSS FLORIDA INTO THE W ATLC. COLD FRONT ENTERS THE W ATLC THROUGH THE FLORIDA STRAITS TO 23N82W WHERE IT BECOMES STATIONARY ALONG 23N90W INTO THE W BAY OF CAMPECHE NEAR 20N95W. SCATTERED SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS ARE S OF 26N BETWEEN 80W-87W. THE POLAR JET HAS RETREATED N LEAVING THE SUBTROPICAL JETSTREAM OVER THE N GULF WITH WINDS TO 120 KT N OF 24N TO OVER THE FLORIDA PENINSULA. THE BROAD UPPER RIDGE IN THE CARIBBEAN IS ADVECTING TROPICAL MOISTURE ACROSS CENTRAL AMERICA AND THE YUCATAN AND PROVIDING UPPER LEVEL DIFFLUENCE ENHANCING THE SHOWERS/THUNDERSTORMS ASSOCIATED WITH THE FRONT. A SURFACE HIGH IS BUILDING OVER THE N GULF IN THE WAKE OF THE ABOVE FRONT WITH A 1026 MB HIGH OFF THE N GULF COAST NEAR 29N87W A GIVING THE W GULF RETURN FLOW BANKING LOW LEVEL CLOUDS ACROSS THE AREA W OF 90W TO THE E SLOPES OF THE SIERRA MADRE MOUNTAINS OF MEXICO. THE FRONT WILL CONTINUE TO WEAKEN OVER THE NEXT DAY OR SO WITH THE NEXT COLD FRONT ENTERING THE GULF FRI. CARIBBEAN... BROAD UPPER LEVEL RIDGE REMAINS OVER MOST OF THE CARIBBEAN ANCHORED OVER SOUTH AMERICA WITH THE AXIS EXTENDING FROM THE COLOMBIA TO E CUBA THEN CONTINUING NE INTO THE W ATLC. BROAD SW FLOW ALOFT IS DRAWING MOISTURE FROM THE E PACIFIC ACROSS CENTRAL AMERICA AS FAR N AS CUBA AS THIN HIGH CLOUDS. AN UPPER LEVEL TROUGH OVER THE CENTRAL ATLC COVERS THE E CARIBBEAN E OF 70W. STRONG SUBSIDENCE AND DRY STABLE AIR COVERS THE CARIBBEAN E OF 75W INCLUDING THE LESSER ANTILLES. FRESH TO STRONG EASTERLY TRADE WINDS ARE USHERING IN SOME ISOLATED PATCHES OF SHOWERS MOSTLY OVER THE GREATER ANTILLES. LITTLE CHANGE IS EXPECTED ACROSS THE REGION FOR THE REMAINDER OF THE WEEK. ATLANTIC... DEEP LAYERED TROUGH THAT COVERS THE E HALF OF THE U.S. AND GULF OF MEXICO EXTENDS INTO THE W ATLC N OF 26N W OF 69W. COLD FRONT ENTERS THE ATLC NEAR 32N68W EXTENDING ACROSS THE N BAHAMAS INTO THE FLORIDA STRAITS NEAR 24N80W THEN CONTINUING INTO THE GULF OF MEXICO. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 120 NM E OF THE FRONT N OF 28N WITH SCATTERED SHOWERS WITHIN 90 NM ON EITHER SIDE OF THE REMAINDER OF THE FRONT. THE UPPER RIDGE AXIS FROM THE CARIBBEAN EXTENDS FROM ACROSS E CUBA TO BEYOND 32N61W. A DEEP LAYERED TROUGH EXTENDS ACROSS THE CENTRAL ATLC FROM AN UPPER LOW IN THE E ATLC NEAR 29N36W SW TO A SECOND UPPER LOW IN THE W TROPICAL ATLC NEAR 17N52W ACROSS THE LESSER ANTILLES INTO THE E CARIBBEAN TO NEAR 13N70W. THE ASSOCIATED COLD FRONT EXTENDS FROM A 1019 MB LOW NEAR 29N35W E ALONG 29N33W THEN S TO 25N35W WHERE IT DISSIPATES W ALONG 23N39W TO 24N45W. ISOLATED SHOWERS N OF 27N FROM 32W-39W. A SURFACE RIDGE COVERS THE CENTRAL ATLC BETWEEN THE FRONTS ANCHORED BY A 1031 MB HIGH JUST N OF THE REGION NEAR 33N49W. THE TYPICAL E/W UPPER RIDGE COVERS THE REMAINDER OF THE TROPICS BUT IS AMPLIFYING N OVER THE E ATLC. A JETSTREAM WITH WINDS OF 90 TO 150 KT IS WITHIN 250/350 NM IS ALONG THE N PERIPHERY EXTENDING FROM 15N45W 29N21W ACROSS THE CANARY ISLANDS TO INLAND OVER W AFRICA NEAR 27N13W WITH THE STRONGEST WINDS OF 130 TO 150 KT WITHIN 75 NM OF LINE FROM 24N36W TO 30N21W. THIS UPPER FLOW IS ALSO ADVECTING TROPICAL MOISTURE WITHIN 325 NM OF LINE FROM 10N45W TO N OF THE CAPE VERDE ISLANDS NEAR 21N20W. $$ WALLACE