000 AXNT20 KNHC 030003 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI SEP 02 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... THE CENTER OF HURRICANE KATIA AT 02/2100 UTC IS NEAR 18.4N 53.5W. THIS POSITION ALSO IS ABOUT 580 NM TO THE EAST OF THE NORTHEASTERN CARIBBEAN SEA ISLANDS. KATIA IS MOVING NORTHWESTWARD 10 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 989 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 65 KT WITH GUSTS TO 80 KT. PLEASE READ THE LATEST INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADER MIATCPAT2/WTNT32 KNHC AND THE FULL FORECAST/ ADVISORY UNDER AWIPS/WMO HEADER MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. NUMEROUS STRONG CONVECTIVE PRECIPITATION COVERS THE ATLANTIC OCEAN FROM 17N TO 21N BETWEEN 51W AND 55W. UPPER LEVEL ANTICYCLONIC OUTFLOW THAT IS SPIRALING OUTWARD AND AWAY FROM KATIA REACHES 32N46W. THE CENTER OF TROPICAL STORM LEE AT 03/0000 UTC IS NEAR 27.8N 91.6W. THIS POSITION ALSO IS ABOUT 180 MILES TO THE WEST-SOUTHWEST OF THE MOUTH OF THE MISSISSIPPI RIVER. LEE IS MOVING NORTHWARD 3 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1001 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 40 KT WITH GUSTS TO 50 KT. PLEASE READ THE LATEST INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADER MIATCPAT3/WTNT33 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADER MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. NUMEROUS STRONG CONVECTIVE PRECIPITATION COVERS THE GULF OF MEXICO AND COASTAL LOUISIANA FROM 28N TO 29N BETWEEN 90W AND 91W. SCATTERED MODERATE TO STRONG CONVECTIVE PRECIPITATION IS IN CLUSTERS IN THE CENTRAL SECTIONS OF THE GULF OF MEXICO...FROM 23N TO 26N BETWEEN 85W AND 92W. NUMEROUS STRONG CONVECTIVE PRECIPITATION IS IN THE WESTERN HALF OF THE YUCATAN PENINSULA. AN ATLANTIC OCEAN 1004 MB LOW PRESSURE CENTER IS NEAR 39N62W. THIS LOW CENTER IS ABOUT 340 NM TO THE SOUTH OF HALIFAX NOVA SCOTIA. UPPER LEVEL WINDS ARE BECOMING UNFAVORABLE FOR THIS FEATURE TO DEVELOP INTO A TROPICAL CYCLONE. THE LOW IS BECOMING ASSOCIATED WITH A FRONTAL SYSTEM. THIS SYSTEM HAS A LOW CHANCE...10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES TOWARD THE NORTHEAST AT 10 TO 15 MPH. ADDITIONAL INFORMATION ON THIS SYSTEM CAN BE FOUND IN HIGH SEAS FORECASTS ISSUED BY THE NOAA OCEAN PREDICTION CENTER...UNDER AWIPS HEADER NFDHSFAT1 AND WMO HEADER FZNT01 KWBC. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 18N29W 13N31W...TO A 1011 MB LOW PRESSURE CENTER THAT IS NEAR 13N31W. ISOLATED MODERATE CONVECTIVE PRECIPITATION IS FROM 12N TO 19N BETWEEN 30W AND 33W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH THE AFRICA COAST NEAR 17N16W TO 15N18W. THE MONSOON TROUGH CONTINUES FROM 12N24W TO 10N31W 7N37W AND 8N42W. ISOLATED MODERATE CONVECTIVE PRECIPITATION IS FROM 6N TO 10N BETWEEN 20W AND 24W...AND FROM 4N TO 9N BETWEEN 30W AND 50W. CLUSTERS OF STRONG CONVECTIVE PRECIPITATION ARE IN AFRICA FROM 12N TO 13N BETWEEN 14W AND 17W. ...DISCUSSION... THE GULF OF MEXICO... THE MAIN FOCUS OF INTEREST RIGHT NOW IS TROPICAL STORM LEE IN THE NORTH CENTRAL PART OF THE AREA. PLEASE REFER TO THE SPECIAL FEATURES SECTION FOR ALL THE INFORMATION ABOUT THIS SYSTEM. MOST IF NOT ALL THE PRECIPITATION THAT IS OCCURRING TO THE NORTH OF 23N BETWEEN 85W AND 92W IS EITHER DIRECTLY RELATED TO TROPICAL STORM LEE AND/OR AT THE PERIPHERY OF THE LARGER-SCALE FLOW THAT IS AROUND LEE. UPPER LEVEL NORTHERLY WIND FLOW MOVES ACROSS FLORIDA...ON THE WESTERN SIDE OF AN UPPER LEVEL TROUGH THAT IS DIGGING INTO THE WINDWARD PASSAGE. THE CARIBBEAN SEA... AN UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 17N65W... ABOUT 90 NM TO THE SOUTHEAST OF PUERTO RICO. RAINSHOWERS ARE POSSIBLE WITHIN 60 NM OF THE CENTER IN THE NORTHERN SEMICIRCLE. AN UPPER LEVEL TROUGH PASSES THROUGH 32N71W IN THE ATLANTIC OCEAN...INTO THE WINDWARD PASSAGE. ISOLATED MODERATE CONVECTIVE PRECIPITATION IS IN THE CARIBBEAN SEA TO THE NORTH OF 14N BETWEEN HISPANIOLA AND 80W. UPPER LEVEL NORTHERLY WIND FLOW CONTINUES TO PUSH SOUTHWARD AS FAR AS 14N IN THE CARIBBEAN SEA BETWEEN 70W AND 80W. UPPER LEVEL NORTHEASTERLY WIND FLOW IS TO THE WEST OF 80W. THE MONSOON TROUGH PASSES THROUGH THE PENINSULA DE LA GUAJIRA OF NORTHEASTERN COLOMBIA TO 12N80W...AND BEYOND SOUTHERN NICARAGUA INTO THE EASTERN PACIFIC OCEAN. BROKEN TO OVERCAST MULTILAYERED CLOUDS ARE TO THE SOUTH OF 13N TO THE WEST OF LA PENINSULA DE LA GUAJIRA OF COLOMBIA. NUMEROUS STRONG CONVECTIVE PRECIPITATION COVERS COSTA RICA AND SOUTHERN NICARAGUA FROM 9N TO 12N. THE ATLANTIC OCEAN... TROPICAL STORM KATIA IS MOVING NORTHWESTWARD...AWAY FROM THE NORTHEASTERN CARIBBEAN SEA. A NARROW UPPER LEVEL TROUGH IS TO THE NORTHWEST OF KATIA...PASSING THROUGH 33N52W TO 27N57W TO 19N60W. ISOLATED TO WIDELY SCATTERED MODERATE CONVECTIVE PRECIPITATION FROM 23N TO 29N BETWEEN 57W AND 64W...AND WITHIN A 30 TO 60 NM RADIUS OF 32N52W. AN UPPER LEVEL TROUGH PASSES THROUGH 32N71W INTO THE WINDWARD PASSAGE. ISOLATED MODERATE CONVECTIVE PRECIPITATION IS IN THE ATLANTIC OCEAN ELSEWHERE TO THE NORTH OF 20N BETWEEN 60W AND 70W...AND FROM 20N TO 26N BETWEEN 70W AND 80W...AND IN THE CARIBBEAN SEA TO THE NORTH OF 14N BETWEEN HISPANIOLA AND 80W. UPPER LEVEL NORTHERLY WIND FLOW CONTINUES TO PUSH SOUTHWARD AS FAR AS 14N IN THE CARIBBEAN SEA. AN UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 28N29W. BROAD CYCLONIC FLOW COVERS THE AREA TO THE NORTH OF 22N BETWEEN 20W AND 34W. SURFACE ANTICYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN TO THE NORTH OF 23N BETWEEN AFRICA AND 63W...MOVING AROUND A 1025 MB HIGH PRESSURE CENTER THAT IS NEAR 33N41W. ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT