000 AXNT20 KNHC 131211 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN JUL 13 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...SPECIAL FEATURE.... BERTHA HAS WEAKENED TO A TROPICAL STORM AND A TROPICAL STORM WARNING REMAINS IN EFFECT FOR BERMUDA. AT 13/1200 UTC BERTHA WAS CENTERED NEAR 29.8N 62.5W...AND IT IS NEARLY STATIONARY. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 988 MB. THE MAXIMUM SUSTAINED WIND SPEED HAS DECREASED TO 60 KT WITH GUSTS TO 75 KT. THIS POSITION ALSO IS 189 NM/350 KM SOUTHEAST OF BERMUDA. PLEASE READ 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 CURRENTLY NEARLY STATIONARY. A DRIFT TOWARD THE NORTHWEST IS EXPECTED TO BEGIN LATER TODAY AND CONTINUE INTO MONDAY. THE CENTER OF BERTHA IS EXPECTED TO PASS SLOWLY AND NOT FAR TO THE SOUTHEAST AND EAST OF BERMUDA DURING THE NEXT COUPLE OF DAYS. THE MOTION MAY BE ERRATIC AT TIMES AND IT MAY BRING THE CENTER OF BERTHA CLOSER TO BERMUDA THAN THE FORECAST TRACK INDICATES. A SLIGHT WEAKENING IS EXPECTED DURING THE NEXT COUPLE OF DAYS. TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 120 NM/220 KM FROM THE CENTER. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 32W/33W SOUTH OF 15N MOVING 10 TO 15 KT. A 1009 MB LOW PRESSURE CENTER IS NEAR 10N ALONG THE WAVE. ITCZ PRECIPITATION IS AND HAS BEEN TO THE WEST OF THE WAVE BETWEEN 36W AND 43W. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 53W/54W SOUTH OF 16N MOVING WEST 15 KT. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG THUNDERSTORMS FROM 10N TO 13N BETWEEN 48W AND 57W. A WESTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 80W/81W SOUTH OF 19N MOVING WEST 15 KT. THIS WAVE STRETCHES FROM WEST OF JAMAICA TO CENTRAL PANAMA. STRONG SHOWERS AND THUNDERSTORMS FROM 10N TO 12N BETWEEN 78W AND 80W MAY OR MAY NOT HAVE ANYTHING TO DO WITH THIS WAVE. ...THE ITCZ... 12N16W 12N24W 9N39W 11N50W 7N60W IN NORTHERN GUYANA. SCATTERED STRONG SHOWERS AND THUNDERSTORMS FROM 5N TO 6N BETWEEN 39W AND 43W...AND FROM 7N TO 9N BETWEEN 59W AND 60W IN NORTHWESTERN GUYANA. SCATTERED MODERATE TO STRONG SHOWERS AND THUNDERSTORMS FROM 7N TO 9N BETWEEN 15W AND 23W. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG THUNDERSTORMS ELSEWHERE FROM 2N TO 12N BETWEEN 35W AND 45W. ...DISCUSSION... THE GULF OF MEXICO...AND THE ATLANTIC OCEAN WEST OF 70W... A MIDDLE TO UPPER LEVEL TROUGH IS FORMING FROM THE ATLANTIC OCEAN NEAR 32N78W TO NORTHERN FLORIDA INTO THE EASTERN AND SOUTHEASTERN GULF OF MEXICO. SHOWERS AND THUNDERSTORMS ARE NORTH OF 27N EAST OF 86W TO THE FLORIDA WEST COAST. A MIDDLE TO UPPER LEVEL TROUGH RUNS FROM EASTERN CUBA ACROSS THE BAHAMAS TO 32N75W IN THE ATLANTIC OCEAN. SHOWERS AND THUNDERSTORMS COVER THE WATERS FROM CUBA TO 27N BETWEEN 74W AND 78W OVER THE BAHAMAS. A SMALL MIDDLE TO UPPER LEVEL CYCLONIC CIRCULATION CENTER HAS MOVED INTO THE CENTRAL PART OF THE SOUTHWESTERN CORNER OF THE AREA...NORTH OF THE ISTHMUS OF TEHUANTEPEC. A MIDDLE TO UPPER LEVEL TROUGH COVERS INTERIOR MEXICO WEST OF 100W PRODUCING WIDESPREAD PRECIPITATION WEST OF 30N104W 24N107W. THE CARIBBEAN SEA... THE TAIL END OF A MIDDLE TO UPPER LEVEL TROUGH THAT STARTS NEAR 32N75W IN THE ATLANTIC OCEAN TO EASTERN CUBA REACHES THE NORTHWESTERN CORNER OF THE AREA. SOME MIDDLE TO UPPER LEVEL CYCLONIC FLOW FROM THE SOUTHWESTERN GULF OF MEXICO CYCLONIC CIRCULATION CENTER REMAINS IN THE WATERS EAST OF THE YUCATAN PENINSULA/NORTH OF HONDURAS. STRONG SHOWERS AND THUNDERSTORMS PERSIST UNDER EXTENSIVE UPPER LEVEL ANTICYCLONIC OUTFLOW WITH AN UPPER LEVEL RIDGE AND A MIDDLE LEVEL TROUGH IN THE SOUTHWESTERN CORNER OF THE AREA. THE STRONG SHOWERS AND THUNDERSTORMS ARE FROM 12N TO 14N BETWEEN 80W AND 86W INCLUDING IN EASTERN AND NORTHEASTERN NICARAGUA. MIDDLE TO UPPER LEVEL DRY AIR IN SUBSIDENCE IS EAST OF 70W AND EAST OF 72W SOUTH OF HISPANIOLA. BROAD MIDDLE TO UPPER LEVEL ANTICYCLONIC FLOW IS NORTH OF 16N BETWEEN 60W AND 70W. A MIDDLE LEVEL CYCLONIC CIRCULATION IN THE DRY AIR/SUBSIDENCE IS NEAR 14N64W. THE REST OF THE ATLANTIC OCEAN EAST OF 70W... A MIDDLE TO UPPER LEVEL TROUGH REMAINS ABOUT 900 NM EAST OF HURRICANE BERTHA...THROUGH 33N46W TO 23N46W. A SURFACE TROUGH IS ALONG 46W/47W NORTH OF 32N. ISOLATED MODERATE SHOWERS ARE NORTH OF 29N BETWEEN 43W AND 47W. BROAD MIDDLE TO UPPER LEVEL CYCLONIC FLOW FROM 10N TO 20N BETWEEN 30W AND 34W IS AROUND A WEAK AND POSSIBLY STILL-FORMING CYCLONIC CENTER NEAR 14N35W. $$ MT