000 AXNT20 KNHC 211205 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE AUG 21 2007 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...SPECIAL FEATURE... THE CENTER OF CATEGORY FIVE HURRICANE DEAN AT 21/1200 UTC IS NEAR 18.9N 88.7W...OR ABOUT 40 MILES...60 KM...NORTHWEST OF CHETUMAL MEXICO AND ABOUT 135 MILES...220 KM...EAST-SOUTHEAST OF CAMPECHE MEXICO. HURRICANE DEAN IS MOVING WEST NEAR 20 MPH. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 125 MPH WITH HIGHER GUSTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 935 MB. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC AND THE LATEST PUBLIC ADVISORY UNDER MIATCPAT4/WTNT34 KNHC FOR MORE DETAILS. REPORTS FROM AN AIR FORCE HURRICANE HUNTER PLANE INDICATE THAT THE EYE OF DEAN MADE LANDFALL ON THE EAST COAST OF THE YUCATAN PENINSULA NEAR COSTA MAYA OR MAJAHUAL AROUND 21/0830 UTC. ...TROPICAL WAVES... AN EASTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 65W/66W SOUTH OF 29N MOVING WEST 15 KT. A 1014 MB LOW PRESSURE CENTER DEVELOPED ALONG THE WAVE NEAR 24.5N. DEVELOPMENT...IF ANY...OF THIS SYSTEM IS EXPECTED TO BE SLOW TO OCCUR AS IT MOVES WESTWARD NEAR 20 MPH OVER THE NEXT DAY OR TWO. STRONG SHOWERS AND THUNDERSTORMS FROM 26N TO 27N BETWEEN 63W AND 66W. ISOLATED MODERATE FROM 20N TO 28N BETWEEN 50W AND 71W...FROM 10N TO 20N BETWEEN 56W AND 63W...AND FROM 15N TO 19N BETWEEN 65W AND 68W INCLUDING ON TOP OF PUERTO RICO. THIS WAVE CONTINUES TO MOVE IN PHASE WITH THE CYCLONIC FLOW AROUND THE ELONGATED PUERTO RICO CYCLONIC CIRCULATION CENTER. SHOWERS AND THUNDERSTORMS ALSO ARE ON TOP OF THE EASTERN CARIBBEAN SEA ISLANDS FROM BARBADOS TO BARBUDA. ...THE ITCZ... FROM THE AFRICA COAST NEAR 12N16W TO 11N30W 9N49W 15N60W. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS FROM 7N TO 8.5N BETWEEN 40W AND 44W...FROM 9N TO 11N BETWEEN 46W AND 48W... AND FROM 8N TO 9N BETWEEN 50W AND 53W. ISOLATED MODERATE SHOWERS AND LOCALLY STRONG THUNDERSTORMS FROM 7N TO 12N BETWEEN AFRICA AND 20W IN BROAD LOW PRESSURE...AND ELSEWHERE FROM 3N TO 14N BETWEEN 30W AND 56W. THE PRECIPITATION FROM 10N TO 20N BETWEEN 56W AND 60W ALSO IS EAST OF THE 65W/66W TROPICAL WAVE...AND PART OF THE ITCZ PRECIPITATION. DISCUSSION... THE GULF OF MEXICO... REPORTS FROM AN AIR FORCE HURRICANE HUNTER PLANE INDICATE THAT THE EYE OF DEAN MADE LANDFALL ON THE EAST COAST OF THE YUCATAN PENINSULA NEAR COSTA MAYA OR MAJAHUAL AROUND 21/0830 UTC. THIS LOCATION ALSO IS ABOUT 40 MILES/65 KM EAST-NORTHEAST OF CHETUMAL MEXICO. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS FROM 17N TO 20N BETWEEN 87W AND 90W. SCATTERED STRONG SHOWERS AND THUNDERSTORMS ARE IN A RAINBAND WITHIN 30 NM ON EITHER SIDE OF 16N84W 19N85W 21N86W 21N88W 21N90W...IN THE EASTERN PACIFIC OCEAN FROM 12N TO 13N BETWEEN 87W AND 90W GOING FROM THE COAST OF NORTHWESTERN NICARAGUA WESTWARD...AND IN A FARTHER-AWAY BAND WITHIN 30 TO 60 NM ON EITHER SIDE OF 11N76W 16N80W. UPPER LEVEL ANTICYCLONIC OUTFLOW EASILY REACHES THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO. UPPER LEVEL RIDGING EXTENDS FROM THE YUCATAN CHANNEL NORTHEASTWARD INTO THE NORTHEASTERN GULF OF MEXICO. THE MIDDLE TO UPPER LEVEL CYCLONIC CIRCULATION CENTER FROM THE LAST FEW DAYS NOW IS INLAND IN THE LOWER VALLEY OF TEXAS NEAR 27N98W. THE ORIENTATION OF THE CYCLONIC FLOW AROUND THIS CYCLONIC CENTER IS NORTHEAST-TO-SOUTHWEST...FROM SOUTHWESTERN LOUISIANA TO THE TEXAS COAST TO COASTAL MEXICO NEAR 20N101W. THE WEATHER WILL CONTINUE TO DETERIORATE THIS MORNING AND FOR THE NEXT DAY OR TWO FROM THE YUCATAN PENINSULA WESTWARD INTO THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO... AND EVENTUALLY IN WHICHEVER PART OF MEXICO THAT IS AFFECTED AS HURRICANE DEAN CONTINUES ITS COURSE. THE CARIBBEAN SEA... REPORTS FROM AN AIR FORCE HURRICANE HUNTER PLANE INDICATE THAT THE EYE OF DEAN MADE LANDFALL ON THE EAST COAST OF THE YUCATAN PENINSULA NEAR COSTA MAYA OR MAJAHUAL AROUND 21/0830 UTC. THIS LOCATION ALSO IS ABOUT 40 MILES/65 KM EAST-NORTHEAST OF CHETUMAL MEXICO. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS FROM 17N TO 20N BETWEEN 87W AND 90W. SCATTERED STRONG SHOWERS AND THUNDERSTORMS ARE IN A RAINBAND WITHIN 30 NM ON EITHER SIDE OF 16N84W 19N85W 21N86W 21N88W 21N90W...IN THE EASTERN PACIFIC OCEAN FROM 12N TO 13N BETWEEN 87W AND 90W GOING FROM THE COAST OF NORTHWESTERN NICARAGUA WESTWARD...AND IN A FARTHER-AWAY BAND WITHIN 30 TO 60 NM ON EITHER SIDE OF 11N76W 16N80W. AN ELONGATED MIDDLE TO UPPER LEVEL CYCLONIC CIRCULATION CENTER NOW IS ALONG THE SOUTHERN COAST OF THE DOMINICAN REPUBLIC NEAR 70W. CYCLONIC FLOW AROUND THIS CENTER COVERS THE CARIBBEAN SEA AND ATLANTIC OCEAN FROM 12N TO 30N BETWEEN 60W AND 80W. THE UPPER LEVEL RIDGE FROM HURRICANE DEAN PASSES THROUGH THE YUCATAN CHANNEL INTO THE NORTHEASTERN GULF OF MEXICO. THE TROPICAL WAVE IS ALONG 65W/66W SOUTH OF 29N MOVING WEST 15 KT. THIS WAVE CONTINUES TO MOVE IN PHASE WITH THE CYCLONIC FLOW AROUND THE ELONGATED DOMINICAN REPUBLIC CYCLONIC CIRCULATION CENTER. SHOWERS AND THUNDERSTORMS COVER THE AREAS FROM 10N TO 28N BETWEEN 50W AND 71W. THE ATLANTIC OCEAN... THE MIDDLE LEVEL ANTICYCLONIC CIRCULATION CENTER NEAR 30N75W STILL IS GUIDING THE DIRECTION OF HURRICANE DEAN. THE CYCLONIC FLOW AROUND THE DOMINICAN REPUBLIC MIDDLE TO UPPER LEVEL CYCLONIC CENTER IS CUTTING INTO THE AREA ON THE SOUTH SIDE OF THE ANTICYCLONIC CENTER. SHOWERS AND THUNDERSTORMS FROM 10N TO 28N BETWEEN 50W AND 71W ARE RELATED TO THE CYCLONIC CENTER AND THE 65W/66W TROPICAL WAVE. A MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION CENTER NEAR 33N33W TO 27N35W AND 21N38W. MIDDLE TO UPPER LEVEL DRY AIR/SUBSIDENCE IS WITHIN 500 NM TO THE EAST OF THE TROUGH. A SURFACE RIDGE PASSES THROUGH 33N50W TO BERMUDA TO THE SOUTHEASTERN GEORGIA COAST. $$ MT