000 AXNT20 KNHC 111808 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU AUG 11 2011 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 21W/22W FROM A 1011 MB LOW PRESSURE CENTER THAT IS NEAR 10N ALONG THE WAVE TO 18N. STRONG RAINSHOWERS AND THUNDERSTORMS ARE FROM 11N TO 12N BETWEEN 21W AND 23W...AND FROM 11N TO 12N BETWEEN 26W AND 27W. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BECOME GRADUALLY MORE CONDUCIVE FOR DEVELOPMENT INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD 15 TO 20 MPH. A 1010 MB LOW PRESSURE CENTER IS NEAR 13N34W. THIS LOW CENTER IS EMBEDDED IN THE MONSOON TROUGH AND AT THE SOUTHERN END OF A TROPICAL WAVE THAT IS ALONG 13N34W 16N37W 19N41W. STRONG RAINSHOWERS AND THUNDERSTORMS ARE FROM 15N TO 16N BETWEEN 36W AND 38W. WIDELY SCATTERED MODERATE RAINSHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE FROM 7N TO 13N BETWEEN 32W AND 38W. ENVIRONMENTAL CONDITIONS APPEAR TO BE FAVORABLE FOR GRADUAL DEVELOPMENT INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WEST-NORTHWESTWARD 15 MPH. ...TROPICAL WAVES... A CARIBBEAN SEA TROPICAL WAVE IS ALONG 20N72W 16N73W 12N73W 19N57W. THIS WAVE IS A WAVE THAT DEVELOPED A FEW DAYS AGO AFTER AN EARLIER WAVE THAT WAS MOVING THROUGH THE ATLANTIC OCEAN TOWARD THE EASTERN CARIBBEAN SEA WEAKENED AND DISSIPATED. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION ACCOMPANIES THIS WAVE. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH THE PRIME MERIDIAN ALONG 21N TO 23N10W 21N17W 15N18W 10N22W 14N30W 13N39W 5N45W. THE ITCZ CONTINUES FROM 5N45W INTO NORTHEASTERN BRAZIL TO THE EQUATOR ALONG 52W. RAINSHOWERS ARE POSSIBLE FROM 7N TO 8N BETWEEN 40W AND 45W...AND FROM 6N TO 10N TO THE WEST OF 50W...AND IN NORTHEASTERN FRENCH GUIANA ALONG THE BORDER WITH BRAZIL. ...DISCUSSION... THE GULF OF MEXICO... BROAD UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE AREA. SCATTERED MODERATE RAINSHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE ABOUT 70 NM TO THE SOUTH OF THE COAST OF THE FLORIDA PANHANDLE BETWEEN THE FLORIDA BIG BEND AND THE ALABAMA/ MISSISSIPPI BORDER. RAINSHOWERS ARE POSSIBLE IN FLORIDA AND COASTAL WATERS ON EITHER SIDE OF THE STATE TO THE SOUTH OF 27N...WITH THE 30N80W 28N82W SURFACE TROUGH THAT REACHES FLORIDA FROM THE ATLANTIC OCEAN...AND THE ATLANTIC OCEAN 29N77W TO 25N79W SURFACE TROUGH. THE CARIBBEAN SEA... AN UPPER LEVEL TROUGH EXTENDS FROM AN ATLANTIC OCEAN 30N68W CYCLONIC CIRCULATION CENTER...TO A 22N76W CYCLONIC CENTER THAT IS BETWEEN THE BAHAMAS AND CUBA...TO 20N80W...TO A CYCLONIC CIRCULATION CENTER THAT IS ON TOP OF THE YUCATAN PENINSULA. RAINSHOWERS ARE POSSIBLE TO THE NORTH OF 15N TO THE WEST OF 80W. RAINSHOWERS ARE POSSIBLE TO THE EAST OF NICARAGUA FROM 12N TO 15N BETWEEN 80W AND THE COAST. A TROPICAL WAVE IS ALONG 20N72W 16N73W 12N73W 19N57W. THIS WAVE IS A WAVE THAT DEVELOPED A FEW DAYS AGO AFTER AN EARLIER WAVE THAT WAS MOVING THROUGH THE ATLANTIC OCEAN TOWARD THE EASTERN CARIBBEAN SEA WEAKENED AND DISSIPATED. NO SIGNIFICANT DEEP CONVECTIVE PRECIPITATION ACCOMPANIES THIS WAVE. THE MONSOON TROUGH PASSES THROUGH 10N73W IN NORTHERN COLOMBIA...TO 11N80W AND BEYOND NORTHERN COSTA RICA. SCATTERED TO NUMEROUS STRONG RAINSHOWERS AND THUNDERSTORMS ARE TO THE SOUTH OF 11N BETWEEN 77W AND THE SOUTHEASTERN COAST OF NICARAGUA AND THE COAST OF COSTA RICA. AN UPPER LEVEL TROUGH PASSES THROUGH THE ATLANTIC OCEAN NEAR 16N53W...INTO THE EASTERN CARIBBEAN SEA TO A 16N67W CYCLONIC CENTER. BROAD UPPER LEVEL CYCLONIC FLOW COVERS THE AREA TO THE EAST OF 70W. THE ATLANTIC OCEAN... AN UPPER LEVEL TROUGH THAT PARALLELS THE U.S.A. EAST COAST AND THAT PASSES THROUGH 32N75W TO 28N82W...SUPPORTS A STATIONARY FRONT THAT ENDS NEAR 31N75W. ONE SURFACE TROUGH IS ALONG 29N77W...ACROSS THE NORTHERN BAHAMAS...TO 25N79W. A SECOND SURFACE TROUGH IS ALONG 30N80W INTO FLORIDA NEAR 28N82W. ISOLATED MODERATE RAINSHOWERS TO LOCALLY STRONG THUNDERSTORMS ARE WITHIN 100 NM ON EITHER SIDE OF THE LINE THAT PASSES THROUGH 32N73W TO 28N76W TO 24N80W IN THE FLORIDA STRAITS. RAINSHOWERS ARE POSSIBLE TO THE NORTH OF 30N BETWEEN 50W AND 67W. AN UPPER LEVEL TROUGH PASSES THROUGH 33N48W TO 27N53W. THIS SUPPORTS A SURFACE TROUGH PASSES THROUGH 32N47W TO 26N50W AND 20N55W. UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN AND THE CARIBBEAN SEA FROM 17N TO 27N BETWEEN 48W AND 70W. SCATTERED MODERATE RAINSHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE FROM 31N TO 33N BETWEEN 46W AND 48...AND FROM 24N TO 26N BETWEEN 51W AND 55W. RAINSHOWERS ARE POSSIBLE ELSEWHERE FROM 17N TO 30N BETWEEN 50W AND 60W. AN UPPER LEVEL TROUGH PASSES THROUGH 32N44W TO 25N47W...TO AN UPPER LEVEL CYCLONIC CIRCULATION CENTER THAT IS NEAR 16N53W...INTO THE CARIBBEAN SEA TO A 16N67W CYCLONIC CENTER. A SURFACE RIDGE PASSES THROUGH 32N35W TO 26N41W 22N48W. SURFACE ANTICYCLONIC WIND FLOW MOVES AROUND A 1018 MB HIGH PRESSURE CENTER THAT IS NEAR 25N62W. CYCLONIC FLOW COVERS THE ATLANTIC OCEAN TO THE NORTH OF 18N BETWEEN THE 32N47W 20N55W SURFACE TROUGH AND 71W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT