000 AXNT20 KNHC 041805 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE SEP 04 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... FELIX MADE LANDFALL ACROSS THE NE COAST OF NICARAGUA EARLY THIS MORNING. THE CENTER OF STORM HAS NOW MOVED INLAND ACROSS NRN NICARAGUA. AT 04/1800 UTC FELIX IS CENTERED NEAR 14.2N 84.5W OR ABOUT 75 MI WEST OF PUERTO CABEZAS NICARAGUA...MOVING W AT 12 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 962 MB. MAXIMUM SUSTAINED WIND SPEED HAS DECREASED TO 85 KT WITH GUSTS TO 100 KT. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 KNHC AND THE FULL FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS INCLUDING THE LATEST WATCH AND WARNING INFORMATION. NOW THAT FELIX IS INLAND AND INTERACTING WITH THE ROUGH TERRAIN OF NICARAGUA AND HONDURAS STEADY WEAKENING IS UNDERWAY. THE EYE HAS FILLED AND CLOUD TOPS ARE WARMING. RAINFALL IS NOW ONE OF THE BIGGEST CONCERNS. FELIX IS EXPECTED TO PRODUCE 8 TO 12 INCHES OF RAIN ACROSS NORTHERN NICARAGUA AND EL SALVADOR...WITH 10 TO 15 INCHES OVER MUCH OF HONDURAS. ISOLATED MAXIMUM AMOUNT OF 25 INCHES ARE POSSIBLE IN MOUNTAINOUS AREAS. THESE RAINS WILL LIKELY PRODUCE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES. PERSONS IN FLOOD-PRONE AREAS SHOULD TAKE ALL NECESSARY PRECAUTIONS TO PROTECT LIFE AND PROPERTY. AN AREA OF LOW PRES...ANALYZED 1010 MB...IS CENTERED NEAR 29N75W. VISIBLE SATELLITE IMAGES SHOW THAT THE CLOUD PATTERN ASSOCIATED WITH THE LOW IS STRETCHED. A WELL DEFINED TROUGH HANGS SW FROM THE LOW TO THE STRAITS OF FLORIDA AND EWD FROM THE LOW TO 30N67W. THIS OVERALL STRUCTURE APPEARS NON-TROPICAL IN NATURE. HOWEVER...THE CIRCULATION HAS BECOME BETTER APPARENT AND THIS SYSTEM HAS THE POTENTIAL TO BECOME A TROPICAL OR SUBTROPICAL CYCLONE OVER THE NEXT COUPLE OF DAYS AS IT MOVES SLOWLY AND ERRATICALLY. IR IMAGES AND LIGHTNING DATA SUGGEST THAT SCATTERED SHOWERS AND TSTMS ARE FROM 27N-30N BETWEEN 72W-76W AND WITHIN 45 NM AHEAD OF THE TROUGH. ...TROPICAL WAVES... LARGE TROPICAL WAVE IS ALONG 30W/31W S OF 22N MOVING W 15 KT. THIS AXIS IS ROUGHLY PLACED IN THE MIDDLE OF A STRETCHED GYRE COVERING CLOSE TO A 15 DEG E-W AREA. A FEW SURROUNDING SHIP/BUOY OBSERVATIONS AND A DIRECT QSCAT OVERPASS HELPED DEFINE THE AXIS AND SUGGEST THAT THIS CYCLONIC TURNING IS AT THE SFC. EVEN THOUGH THE WAVE STRUCTURE IS WELL DEFINED...SHOWER ACTIVITY REMAINS VERY LIMITED LIKELY SUPPRESSED BY THE STABLE LOW TO MID LEVEL AIR SURROUNDING THIS FEATURE. TROPICAL WAVE IS ALONG 62W S OF 22N MOVING W 15 KT. THIS WAVE HAS BECOME LESS DEFINED TODAY AND IT IS LIKELY GOING TO SPLIT...IF IT HAS NOT ALREADY...AS THE NRN PART LIES IN A DIFFLUENT LOW LEVEL PATTERN. SHOWER ACTIVITY...OR EVEN ORGANIZED CLOUDINESS...IS MINIMAL. THE 1012 MB LOW TO THE E NEAR 11N40W ...POSSIBLY SPAWNED FROM THIS WAVE...HAS BEEN ON A SLOW DRIFT OVER THE PAST COUPLE OF DAYS. THIS LOW HAS GENERALLY CHANGED LITTLE SINCE YESTERDAY AND IT MAY BECOME SOMEWHAT ABSORBED BY THE LARGE TROPICAL WAVE TO IT'S E. SCATTERED SHOWERS AND TSTMS ARE WITHIN 75 NM OF THE LOW. THE NRN PART OF A TROPICAL WAVE IS OVER PORTIONS OF CENTRAL AMERICA AND THE BAY OF CAMPECHE ALONG 91W/92W MOVING W 10-15 KT. THIS ONCE ACTIVE WAVE IS NO LONGER EASILY DISCERNIBLE IN ANY OF THE AVAILABLE DATA...THEREFORE THE CURRENT POSITION IS BASED ON FORWARD EXTRAPOLATION. SHOWERS AND TSTMS ARE PRIMARILY ACROSS THE EPAC WATERS...SEE THE EAST PACIFIC TWD MIATWDEP FOR DETAILS. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 12N16W 15N27W 12N36W 8N51W 9N58W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE LOCATED WELL S OF THE ANALYZED AXIS NEAR A CONVERGENT ZONE BETWEEN SLY AND SWLY FLOW FROM 5N-7N BETWEEN 17W-47W. DISCUSSION... GULF OF MEXICO... AN ELONGATED UPPER HIGH IS STRETCHED ACROSS THE SRN U.S. AND NRN MEXICO. DIFFLUENT FLOW ALOFT BETWEEN THIS HIGH AND DEEP LAYER TROUGHING FURTHER E IS PRODUCING SCATTERED SHOWERS AND TSTMS ACROSS THE N CENTRAL AND NE GULF FROM 28N-29N BETWEEN THE TAMPA BAY AREA TO THE SRN MISSISSIPPI COAST. LIGHTER LESS ORGANIZED ACTIVITY IS MOSTLY INLAND OVER TEXAS ALSO ASSOCIATED WITH DIFFLUENCE ALOFT AND A LINGERING LOW-LEVEL TROUGH. ENHANCED CONFLUENT UPPER FLOW BETWEEN THE STRETCHED HIGH AND AN UPPER LOW IN THE BAY OF CAMPECHE IS DRYING OUT THE AIR IN THE MID AND UPPER LEVELS...PROVIDING MOSTLY FAIR WEATHER ACROSS MUCH OF THE CENTRAL AND SW GULF. AT THE SFC...A WEAK 1018 MB HIGH IS CENTERED NEAR 28N92W. THIS IS KEEPING WINDS RATHER LIGHT OUT OF THE E TO SE ACROSS THE REGION. CARIBBEAN SEA... HURRICANE FELIX IS THE MAIN FOCUS THIS MORNING AS IT MOVES FURTHER INLAND OVER NICARAGUA AND HONDURAS. FOR MORE DETAILS ON FELIX REFER TO THE SPECIAL FEATURE SECTION ABOVE. THE INTERACTION BETWEEN AN UPPER LOW IN THE SE CARIB NEAR 13N64W AND A WEAK TROPICAL WAVE IS PRODUCING SOME CLOUDINESS AND ISOLATED SHOWERS ACROSS THE WINDWARD ISLANDS. NELY UPPER FLOW BETWEEN THE UPPER LOW AND A MID-TO UPPER RIDGE TO THE N IS PRODUCING A FAIR AMOUNT OF DRY STABLE AIR ALOFT...SUPPRESSING DEEP CLOUDINESS BETWEEN THE WINDWARD ISLANDS AND 70W. A CLUSTER OF TSTMS HAS DEVELOPED OVER NRN VENEZUELA...LIKELY TIED TO THE ITCZ. ATLANTIC OCEAN... AN AREA OF LOW PRES CENTERED BETWEEN BERMUDA AND THE NE FLORIDA COAST IS ORGANIZING. FOR MORE DETAILS REFER TO THE SPECIAL FEATURE SECTION ABOVE. ANOTHER LOW PRES SYSTEM...1014 MB...IS LOCATED ALONG OUR N BORDER NEAR 31N55W. THIS LOW LIES AT THE BASE OF A FRONTAL ZONE. ASSOCIATED SCATTERED SHOWERS AND TSTMS ARE N OF 26N BETWEEN 50W-57W. ELSEWHERE AT THE SFC...A STATIONARY 1023 MB HIGH IS NEAR 28N36W PROVIDING MODERATE RIDGING ACROSS THE CENTRAL AND E ATLC. A WEAK 1016 MB HIGH IS LOCATED FURTHER W NEAR 25N67W. THIS PATTERN HAS ALLOWED TRADES TO REMAIN LIGHT TO MODERATE ACROSS MOST OF THE AREA...SLIGHTLY STRONGER NEAR THE LARGE TROPICAL WAVE IN THE E ATLC. ALOFT...A DOMINATING UPPER HIGH REMAINS PARKED ACROSS THE AREA CENTERED NEAR 24N33W. ABUNDANT DRY AIR IS EMBEDDED WITHIN THIS RIDGE PROVIDING FAIR WEATHER FOR MUCH OF THE CENTRAL AND E ATLC. $$ CANGIALOSI