000 AXNT20 KNHC 142354 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON JUL 14 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 2245 UTC. ...SPECIAL FEATURE.... TROPICAL STORM BERTHA IS CENTERED NEAR 33.4N 64.0W AT 15/0000 UTC OR ABOUT 74 NM NORTH-NORTHEAST OF BERMUDA. THE MINIMUM CENTRAL PRESSURE IS 995 MB. THE MAXIMUM SUSTAINED WIND SPEED IS 60 KT WITH GUSTS TO 75 KT. A HURRICANE WATCH AND A TROPICAL STORM WARNINGS ARE IN EFFECT FOR BERMUDA. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC AND THE PUBLIC ADVISORY UNDER MIATCPAT2/WTNT32 KNHC FOR MORE DETAILS. BERTHA IS GRADUALLY INTENSIFYING AND IS EXPECTED TO BECOME A HURRICANE AGAIN DURING THE NEXT 24 HOURS. THERE IS SOME CHANCE THAT THIS COULD OCCUR BEFORE THE STRONGEST WINDS MOVE PAST BERMUDA DURING THE NEXT SEVERAL HOURS. LARGE SWELLS AND HIGH SURF ARE AFFECTING BERMUDA AND ARE EXPECTED TO PERSIST FOR THE NEXT DAY OR TWO. DANGEROUS RIP CURRENTS ARE ALSO OCCURRING ALONG THE US EAST COAST FROM THE CAROLINAS THROUGH SOUTHERN NEW ENGLAND. THE DEEPEST CONVECTION IS WITHIN 90/120 OF THE CENTER OVER THE S SEMICIRCLE WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS COVERING A BROAD AREA FROM 30N-35N BETWEEN 61W-67W. STRONG TROPICAL WAVE IS ALONG 43W/44W S OF 18N MOVING W NEAR 15 KT WITH A 1008 MB LOW ANALYZED ALONG THE AXIS NEAR 12N MOVING ROUGHLY WNW NEAR 15 KT. SATELLITE IMAGERY SHOWS A LARGE WELL DEFINED ENVELOPE OF CYCLONIC ROTATION...FOCUSED NEAR THE LOW CENTER. NO DEEP CONVECTION REMAINS ALTHOUGH SCATTERED SHOWERS ARE POSSIBLE FROM 10N-15N BETWEEN 40W-47W. THIS SYSTEM COULD BECOME A TROPICAL DEPRESSION DURING THE NEXT DAY OR TWO. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 64W/65W S OF 17N MOVING W 15-20 KT. THIS FEATURE REMAINS WELL DEFINED WITH IR SATELLITE IMAGERY SHOWING AN INVERTED-V CURVATURE ALONG THE AXIS. SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE S OF 15N TO INLAND OVER VENEZUELA BETWEEN 59W-70W INCLUDING THE WINDWARD AND ABC ISLANDS. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 12N14W 8N24W 6N36W 8N50W 10N63W AND ACROSS THE SW CARIBBEAN. SCATTERED/NUMEROUS STRONG CONVECTION IS FROM 7N-10N BETWEEN 25W-29W. CLUSTERS OF SCATTERED STRONG CONVECTION ARE FROM 6N-12N BETWEEN 29W-35W. SCATTERED MODERATE/ ISOLATED STRONG CONVECTION IS INLAND AND WITHIN 75 NM ALONG THE COAST OF W AFRICA FROM FROM 10N-13N WITH CLUSTERS OF SIMILAR CONVECTION DOTTING THE AREA WITHIN 150 NM OF THE ITCZ BETWEEN 20W-42W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYERED TROUGH IS OVER THE E US DIPPING S TO THE N GULF COAST GENERATING NUMEROUS SHOWERS/THUNDERSTORMS MAINLY OVER S GEORGIA/NE FLORIDA AND S LOUISIANA INTO E TEXAS. SCATTERED THUNDERSTORMS ARE MOVING W TO E ACROSS THE FLORIDA PENINSULA. STRONG SUBSIDENCE AND DRY STABLE AIR ARE N OF THE STATIONARY BOUNDARY THAT EXTENDS ACROSS CENTRAL GEORGIA ACROSS S ALABAMA TO CENTRAL LOUISIANA AND CENTRAL TEXAS. THE SURFACE RIDGE OVER THE W ATLC CONTINUES TO WEAKEN WITH A 1016 MB HIGH OVER THE W GULF NEAR 25N93W. AN UPPER HIGH IS OVER SW TEXAS WITH THE RIDGE AXIS EXTENDING SE OVER THE GULF OF MEXICO TO NEAR THE FLORIDA KEYS. THIS IS ENHANCING THE THUNDERSTORM ACTIVITY OVER THE N GULF AS WELL AS GENERATING CLUSTERS OF SCATTERED SHOWERS/THUNDERSTORMS OVER THE E GULF E OF 90W. CARIBBEAN SEA... AN UPPER LOW IS IN THE N/CENTRAL CARIBBEAN COVERING THE AREA N OF 15N FROM 70W-82W AND COMBINED WITH THE UPPER RIDGE THAT COVERS THE GULF OF MEXICO IS GENERATING SCATTERED SHOWERS/ THUNDERSTORMS MAINLY OVER CUBA AND ALONG THE ADJACENT COASTAL WATERS AS WELL AS INLAND OVER JAMAICA AND HAITI. THE ITCZ CROSSES THE SW CARIBBEAN FROM COLOMBIA TO COSTA RICA INTO THE E PACIFIC REGION GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 13N W OF 79W. THE E CARIBBEAN IS DOMINATED BY AN UPPER RIDGE ANCHORED IN THE S/CENTRAL ATLC WHICH IS ENHANCING THE ACTIVITY ASSOCIATED WITH THE TROPICAL WAVE. THE CENTRAL CARIBBEAN REMAINS QUIET THIS EVENING ALTHOUGH THERE ARE SOME HIGH LEVEL CLOUDS TRANSVERSING THE AREA FROM W TO E. ATLANTIC OCEAN... TROPICAL STORM BERTHA CONTINUES TO PLAGUE THE AREA JUST N OF THE REGION NEAR BERMUDA...SEE ABOVE. A MID/UPPER LOW IS MOVING NE OUT OF THE REGION ALONG THE E US COAST WITH THE UPPER TROUGH EXTENDING THROUGH 32N76W TO S FLORIDA NEAR FORT LAUDERDALE. A NARROW UPPER RIDGE EXTENDS JUST THE E ENHANCING CLUSTERS OF SCATTERED SHOWERS/THUNDERSTORMS WITHIN 120/130 NM OF LINE FROM 30N74W TO OVER FLORIDA AND INTO THE SE GULF OF MEXICO NEAR 25N80W INCLUDING THE N BAHAMA ISLANDS. A BROAD DEEP LAYERED TROUGH IS OVER THE CENTRAL ATLC N OF 20N BETWEEN 35W-55W WITH THE ASSOCIATED COLD FRONT ALONG THE N PERIPHERY OF THE REGION FROM 43W-50W. A LARGE UPPER LEVEL HIGH IS CENTERED OVER THE S/CENTRAL AND W TROPICAL ATLC NEAR 18N58W AND EXTENDS OVER THE E CARIBBEAN. A SECOND UPPER LEVEL HIGH IS SW OF THE CANARY ISLANDS NEAR 26N22W COVERING THE E ATLC E OF 35W. VISIBLE SATELLITE IMAGERY AS WELL AS REPORTS OF HAZY CONDITIONS OVER THE LESSER ANTILLES INDICATES THE PRESENCE OF AFRICAN DUST S OF 23N E OF 65W ACROSS THE TROPICAL ATLC. $$ WALLACE