000 AXNT20 KNHC 060003 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON SEP 05 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... HURRICANE KATIA IS CENTERED NEAR 25.2N 63.9W AT 05/2100 UTC OR ABOUT 495 MI...795 KM S OF BERMUDA MOVING NW AT 11 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 959 MB. MAXIMUM SUSTAINED WIND SPEED IS 100 KT WITH GUSTS TO 120 KT. PLEASE SEE 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. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 21N-28N BETWEEN 62W-67W. KATIA IS NOW A CATEGORY THREE MAJOR HURRICANE. HURRICANE-FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM...FROM THE CENTER...AND TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 205 MILES...335 KM. LARGE SWELLS GENERATED BY KATIA ARE EXPECTED TO AFFECT MOST OF THE EAST COAST OF THE UNITED STATES...BERMUDA...THE GREATER ANTILLES...AND EAST-FACING BEACHES OF THE BAHAMAS DURING THE NEXT FEW DAYS. THESE SWELLS ARE LIKELY TO CAUSE LIFE-THREATENING SURF AND RIP CURRENT CONDITIONS. A LOW PRESSURE SYSTEM ASSOCIATED TO A TROPICAL WAVE IS NEAR 9N31W MOVING W 10-15 KT. THIS FEATURE IS EMBEDDED WITHIN AN AREA OF DEEP LAYER MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. A CLUSTER OF SCATTERED MODERATE TO STRONG CONVECTION IS NW OF THE CENTER FROM 10N-14N BETWEEN 30W-36W. WIDELY SCATTERED MODERATE CONVECTION IS S OF THE CENTER FROM 5N-9N BETWEEN 29W-34W. ENVIRONMENTAL CONDITIONS ARE CONDUCIVE FOR A UPGRADE TO A TROPICAL DEPRESSION. THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... TROPICAL WAVE IS IN THE CENTRAL TROPICAL ATLANTIC FROM 19N49W TO 13N46W. A 1011 MB LOW IS EMBEDDED ON THE WAVE AXIS NEAR 15N48W. THE SYSTEM IS MOVING W NEAR 15 KT. SCATTERED WEAK TO MODERATE CONVECTION IS WITHIN 120 NM W OF THE WAVE AXIS. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH IS ANALYZED ACROSS AFRICA ENTERING THE ERN TROPICAL ATLANTIC ON THE COAST OF SENEGAL NEAR 16N16W... CONTINUING SW TO 10N26W TO THE SPECIAL FEATURE LOW NEAR 9N31W TO 10N45W. BESIDES THE CONVECTION MENTIONED ON THE SPECIAL FEATURE LOW...ISOLATED MODERATE CONVECTION IS S OF THE MONSOON TROUGH FROM 5N-9N BETWEEN 38W-43W. ...DISCUSSION... GULF OF MEXICO... THE REMNANT LOW OF LEE AT 2100 UTC IS LOCATED AT 32N87.9W OR 95 MILES N OF MOBILE ALABAMA MOVING NE AT 8 KT. FLOOD AND FLASH FLOOD WATCHES AND WARNINGS ARE CURRENTLY IN EFFECT FROM THE CENTRAL GULF COAST STATES NORTHEASTWARD ACROSS THE SOUTHERN AND CENTRAL APPALACHIANS AND INTO NEW ENGLAND. LEE IS NOW EXTRATROPICAL AFTER MERGING WITH A FRONTAL ZONE. THE REMNANTS OF LEE ARE EXPECTED TO PRODUCE TOTAL RAIN ACCUMULATIONS OF 10 TO 15 INCHES ACROSS THE CENTRAL GULF COAST REGION...WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF 20 INCHES THROUGH TUESDAY. A COLD FRONT EXTENDS SW FROM THE LOW CENTER TO THE FLORIDA PANHANDLE AT 30N87W TO THE CENTRAL GULF OF MEXICO AT 26N90W TO N OF TAMPICO MEXICO AT 23M98W. WIDELY SCATTERED MODERATE CONVECTION IS WITHIN 90 NM OF THE FRONT. SIMILAR CONVECTION IS OVER THE BAY OF CAMPECHE S OF 21N W OF 93W. SCATTERED MODERATE TO STRONG CONVECTION IS INLAND OVER THE ENTIRE YUCATAN PENINSULA. FAIR WEATHER IS ALONG THE COAST OF TEXAS BEHIND THE FRONT. EXPECT THE FRONT TO EXTEND FROM N FLORIDA TO THE EASTERN BAY OF CAMPECHE IN 24 HOURS WITH CONVECTION. CARIBBEAN SEA... BESIDES THE CONVECTION OVER THE YUCATAN PENINSULA...WIDELY SCATTERED MODERATE CONVECTION IS INLAND OVER CENTRAL AMERICA FROM PANAMA TO HONDURAS. ISOLATED MODERATE CONVECTION IS OVER THE SW CARIBBEAN FROM 11N-14N BETWEEN 77W-80W. ISOLATED MODERATE CONVECTION IS OVER THE HIGHER ELEVATIONS OF PUERTO RICO...HISPANIOLA...JAMAICA...AND CUBA. THE REMAINDER OF THE CARIBBEAN HAS MOSTLY FAIR WEATHER. 10-20 KT TRADEWINDS DOMINATE OVER THE CARIBBEAN WITH HIGHEST WINDS ALONG THE COAST OF N COLOMBIA. EXPECT CONTINUED CONVECTION OVER CENTRAL AMERICA OVER THE NEXT 24 HOURS. ALSO EXPECT SHOWERS TO ADVECT OVER THE LESSER ANTILLES FROM THE ATLANTIC. ATLANTIC OCEAN... HURRICANE KATIA...THE TROPICAL WAVE/LOW...AND THE SPECIAL FEATURE LOW ARE THE DOMINATED WEATHER PRODUCERS IN THE TROPICAL ATLANTIC. A 1025 MB HIGH IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 33N51W PRODUCING FAIR WEATHER. SCATTERED SHOWERS WITH ISOLATED THUNDERSTORMS ARE E OF THE LESSER ANTILLES FROM 10N-19N BETWEEN 55W-59W MOVING W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA