000 AXNT20 KNHC 280528 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE OCT 28 2008 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 0415 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED ALONG 42W/43W S OF 15N MOVING 2 TO 3 DEGREES OVER THE PAST 24 HOURS. THIS A BROAD AREA OF OF DENSE CLOUD COVER WITH EMBEDDED CLUSTERS OF SCATTERED MODERATE TO SCATTERED STRONG CONVECTION FROM 6N-17N BETWEEN 35W-48W GENERATED BY UPPER DIFFLUENCE BY AN UPPER RIDGE THAT EXTENDS OVER THE TROPICAL ATLC. TROPICAL WAVE IS ALONG 57W/58W S OF 16N MOVING W 10 KT. A WELL DEFINED INVERTED-V CURVATURE IS OBSERVED ON SATELLITE IMAGERY BETWEEN 12N-18N WITH SMALL CLUSTERS OF SCATTERED MODERATE CONVECTION COVERING THE AREA FROM 13N-17N BETWEEN 55W-59W. ...THE ITCZ... ITCZ AXIS IS ANALYZED ALONG 10N13W 7N29W 9N41W 9N55W 8N61W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 3N-11N BETWEEN 16W-34W. ...DISCUSSION... GULF OF MEXICO... A DEEP LAYERED TROUGH COVERS THE E US AND INTO THE GULF N OF 25N WITH A JET STREAM OF 90 TO 120 KT OVER THE NE GULF. THE ASSOCIATED FAST MOVING COLD FRONT TRANSECTS THE GULF PUSHED S BY A 1035 MB HIGH ANCHORED OVER CENTRAL TEXAS. AT 0000 UTC...THE FRONT ACROSS THE CENTRAL FLORIDA FROM THE W ATLC NEAR FORT MYERS ALONG 24N90W TO TO MEXICO NEAR TAMPICO. THE AIR MASS N OF THE FRONT IS RATHER DRY WITH DEW POINTS ALONG THE N GULF COAST DOWN TO THE 20 TO 30 DEGREE RANGE AND TEMPERATURES DROPPING INTO THE 40 TO 50 DEGREE RANGE. LOW CLOUDS WITH ISOLATED SHOWERS DELINEATE THE FRONT AS THE AIR MASS HAS ALREADY BEEN DRIED OUT BY THE PREVIOUS FRONTAL PASSAGE. N WINDS OF 20 TO 30 KT ARE N OF THE FRONT WHICH IS EXPECTED TO PRODUCE STORM FORCE WINDS OVER THE GULF OF TEHUANTEPEC IN E PACIFIC REGION. THE S GULF IS DOMINATED BY SW UPPER WINDS WHICH IS ADVECTING UPPER MOSITURE FROM THE E PACIFIC REGION ACROSS MEXICO TO OVER THE SW GULF MAINLY IN THE FORM OF HIGH CLOUDS. THE FRONT IS EXPECTED TO CLEAR THE ENTIRE GULF DURING THE DAY TUE. CARIBBEAN SEA... THE REMNANTS OF A FRONTAL BOUNDARY THAT PASSED THROUGH THE GULF OF MEXICO EARLIER IN THE WEEKEND REMAINS IN THE CARIBBEAN EXTENDING ACROSS CUBA NEAR 22N81W TO THE GULF OF HONDURAS NEAR 16N88W. THIS FRONT CONTINUES TO PRODUCE SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS WITHIN 90 NM SE OF THE FRONT WITH ISOLATED SHOWERS WITHIN 60 NM NW OF THE FRONT. HAVANA CUBA REPORTED OVER 2 INCHES OF RAIN WITH THE FRONTAL PASSAGE. THE UPPER LEVELS OF THE CARIBBEAN ARE DOMINATED BY AN UPPER RIDGE ANCHORED IN THE W ATLC N OF THE MONA PASSAGE GIVING THE CARIBBEAN E OF THE FRONT STRONG SUBSIDENCE AND DRY STABLE AIR. LOW LEVEL ISOLATED SHOWERS ARE OVER THE NE CARIBBEAN N OF 17N FROM THE VIRGIN ISLANDS TO OVER HAITI. ATLANTIC OCEAN... A DEEP LAYERED TROUGH THAT COVERS THE E US EXTENDS OVER THE FAR W ATLC WITH A WEAKER COLD FRONT ENTERING THE REGION NEAR 32N67W ALONG 26N72W ACROSS THE BAHAMAS AND INTO THE NW CARIBBEAN NEAR 22N81W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 90/120 NM E OF THE FRONT. A SECOND STRONGER AND FASTER MOVING COLD FRONT ENTERS THE W ATLC NEAR 32N77W AND INTO THE GULF OF MEXICO ACROSS CENTRAL FLORIDA S OF DAYTONA BEACH THROUGH FORT MYERS. DENSE LOW LEVEL CLOUDS WITH POSSIBLE ISOLATED SHOWERS ARE WITHIN 120 NM N OF THE STRONG FRONT TO THE FLORIDA COAST. THESE FRONTS ARE EXPECTED TO MERGE IN 12 TO 24 HOURS EXTENDING FROM NEAR BERMUDA TO NEAR THE WINDWARD PASSAGE. BROAD UPPER RIDGE COVERS THE REMAINDER OF THE W ATLC AND INTO THE CENTRAL ATLC ANCHORED N OF THE MONA PASSAGE NEAR 22N68W WITH ENOUGH UPPER DIFFLUENCE OVER THE CENTRAL ATLC TO GENERATE SCATTERED SHOWERS E OF 57W TO A SURFACE TROUGH ANALYZED IN THE CENTRAL ATLC EXTENDING FROM 31N45W ALONG 22N51W THEN W TO JUST N OF THE VIRGIN ISLANDS. A NARROW UPPER LEVEL SHEAR AXIS EXTENDS INTO THE CENTRAL ATLC NEAR 32N42W S TO 21N47W THEN SW TO NEAR TRINIDAD ALONG THE SOUTH AMERICAN COAST. THIS SHEAR AXIS IS ENHANCING THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVE ALONG 57W/58W. A STRONG UPPER RIDGE COVERS THE REMAINDER OF THE TROPICAL ATLC ANCHORED NEAR 11N30W AND COVERS THE AREA S OF 27N E OF THE CENTRAL ATLC SHEAR AXIS. THE UPPER DIFFLUENCE ASSOCIATED WITH THIS UPPER RIDGE IS GENERATING THE CONVECTION SURROUNDING THE TROPICAL WAVE ALONG 42W/43W. $$ WALLACE