000 AXNT20 KNHC 222353 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN JUN 22 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 45W S OF 16N MOVING W NEAR 20-25 KT. BROAD MID LEVEL INVERTED-V CURVATURE IS EVIDENT ON SATELLITE IMAGERY. VERY LITTLE IN THE WAY OF ORGANIZED DEEP CONVECTION ASSOCIATED WITH THE WAVE AT THIS TIME. SCATTERED SHOWERS ARE OBSERVED WITHIN 250 NM ON EITHER SIDE OF THE AXIS BETWEEN 8N-14N. TROPICAL WAVE IS IN THE WRN CARIBBEAN ALONG 84W S OF 21N MOVING W NEAR 20-25 KT. SATELLITE IMAGERY SHOWS WEAK LOW LEVEL INVERTED-V CURVATURE MOVING ACROSS HONDURAS AND NICARAGUA. SCATTERED SHOWERS AND TSTMS ARE FROM 10N-16N BETWEEN 82W-87W. THIS ACTIVITY IS BEING ENHANCED BY UPPER LEVEL DIFFLUENCE. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 12N16W 7N30W 6N42W 5N47W 5N52W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 4N-8N BETWEEN 22W-29W. SIMILAR CONVECTION IS FROM 5N-8N BETWEEN 30W-36W. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM OF A LINE FROM 9N53W TO 8N60W. ...DISCUSSION... GULF OF MEXICO... SHORTWAVE UPPER TROUGH EXTENDS OVER THE WRN GULF WITH AXIS EXTENDING FROM ERN TEXAS ALONG 95W TO NEAR 21N. AN UPPER-LEVEL RIDGE EXTENDS FROM THE CARIBBEAN OVER THE ERN GULF INTO THE FAR W ATLC OVER THE NW BAHAMAS. THIS IS SUPPLYING MOST OF THE GULF WITH WSW UPPER FLOW. SCATTERED SHOWERS AND TSTMS CONTINUE E OF THE TROUGH AXIS ALONG A SURFACE TROUGH WHICH EXTENDS FROM MOBILE ALABAMA TO NEAR 27N93W...CONTINUING AS A SECONDARY SURFACE TROUGH IN THE BAY OF CAMPECHE. MOST INTENSE TSTMS ACCORDING TO LIGHTNING DATA REMAIN FROM 23N-27N BETWEEN 90W-96W. DAYTIME INSTABILITY AND A WEAKENING SURFACE TROUGH ACROSS THE W ATLC AND SRN FLORIDA IS ALSO PROVIDING SCATTERED SHOWERS WITH EMBEDDED TSTMS ACROSS PORTIONS OF THE SE GULF MAINLY BETWEEN 24N-27N BETWEEN THE FLORIDA PENINSULA AND 86W. A WEAK SURFACE RIDGE EXTENDS ACROSS THE GULF FROM THE W ATLC CREATING A WEAK PRESSURE PATTERN AND IS PROVIDING LIGHT AND VARIABLE WINDS ACROSS THE REGION. CARIBBEAN... AN UPPER RIDGE ANCHORED OVER THE GULF OF TEHUANTEPEC IN THE ERN PACIFIC EXTENDS OVER THE BAY OF CAMPECHE AND NW CARIBBEAN W OF 77W WHILE A SECOND UPPER RIDGE ANCHORED IN THE TROPICAL ATLC COVERS THE E CARIBBEAN. AN UPPER TROUGH IS BETWEEN THESE UPPER RIDGES EXTENDING FROM THE CENTRAL ATLC ACROSS PUERTO RICO SW TO NRN COLOMBIA. UPPER LEVEL DIFFLUENCE IS GENERATING SCATTERED SHOWERS/TSTMS ACROSS CUBA AND ADJACENT COASTAL WATERS BETWEEN 77W-80W. TROPICAL WAVE ALONG 84W COUPLED WITH UPPER LEVEL DIFFLUENCE IS PROVIDING SUPPORT FOR SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ALONG THE HONDURAS AND NICARAGUA COASTS. THIS ACTIVITY WILL CONTINUE TO MOVE INLAND ACROSS CENTRAL AMERICA. ELSEWHERE SCATTERED SHOWERS/TSTMS REMAIN ACROSS THE SW CARIBBEAN IN ASSOCIATION WITH THE COLOMBIAN LOW AND EPAC ITCZ. MODERATE TO STRONG EASTERLY TRADE WINDS DOMINATE MOST OF THE CARIBBEAN DUE TO THE TIGHT PRESSURE GRADIENT BETWEEN THE SURFACE RIDGE OVER THE ATLC AND LOWER PRESSURE OVER SOUTH AMERICA. ATLANTIC... BROAD UPPER LEVEL TROUGHING COVERS MUCH OF THE ERN CONUS WITH SW UPPER FLOW ACROSS THE W ATLC WATERS. A SURFACE TROUGH ENTERS THE DISCUSSION AREA NEAR 32N74W AND EXTENDS SW TO 29N77W. THESE TWO FEATURES ARE SUPPORTING SCATTERED SHOWERS AND TSTMS ACROSS SRN FLORIDA...THE NW BAHAMAS AND PORTIONS OF THE W ATLC N OF 24N AND W OF 73W. UPPER LEVEL CYCLONIC CIRCULATION IS CENTERED NEAR 22N60W WITH TROUGHING EXTENDING SW INTO THE CENTRAL CARIBBEAN SEA. A SURFACE RIDGE COVERS THE ENTIRE ATLC BASIN FROM AFRICA INTO THE GULF OF MEXICO ANCHORED BY A 1030 MB HIGH CENTERED NEAR 32N45W. MODERATE SUBSIDENCE AND A FAIR AMOUNT OF DRY STABLE AIR ALSO DOMINATES THE ATLC E OF 75W GIVING THE AREA FAIR WEATHER. BROAD E/W UPPER RIDGE DOMINATES THE TROPICAL ATLC FROM THE CAPE VERDE ISLANDS TO OVER THE ERN CARIBBEAN ENHANCING THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVE ALONG 45W AND THE ITCZ. $$ HUFFMAN