000 AXNT20 KNHC 250603 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE SEP 25 2012 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY VALID THROUGH 0515 UTC. ...SPECIAL FEATURE... THE CENTER OF TROPICAL STORM NADINE AT 25/0300 UTC IS NEAR 32.2N 29.0W. NADINE IS ABOUT 360 NM/670 KM TO THE SOUTH- SOUTHWEST OF THE AZORES. NADINE IS MOVING WESTWARD 6 KNOTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 996 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 40 KNOTS WITH GUSTS TO 50 KNOTS. TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 90 NM IN THE SOUTHERN SEMICIRCLE...150 NM IN THE NORTHEASTERN QUADRANT... AND 160 NM IN THE NORTHWESTERN QUADRANT. PLEASE READ THE FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/ WTNT24 KNHC...AND THE PUBLIC ADVISORY...MIATCPAT4/WTNT34 KNHC... FOR MORE DETAILS. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 30N TO 32N BETWEEN 29W AND 32W. ...TROPICAL WAVE... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 60W TO THE SOUTH OF 18N...MOVING WESTWARD 15 KNOTS DURING THE LAST 24 HOURS. RAINSHOWERS ARE POSSIBLE WITHIN 60 NM ON EITHER SIDE OF THE TROPICAL WAVE. IT IS NOT EASY TO FIND PRECIPITATION THAT ONLY ACCOMPANIES THE WAVE...BECAUSE OF THE MIDDLE LEVEL TO UPPER LEVEL TROUGH THAT IS ALONG 20N65W 14N70W 10N79W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH THE COASTAL GAMBIA TO 14N20W 15N24W 14N27W. THE ITCZ CONTINUES FROM 14N27W TO 10N33W 9N36W 10N42W 11N46W 10N50W. CONVECTIVE PRECIPITATION...NUMEROUS STRONG IN GUINEA-BISSAU AND IN SENEGAL TO THE SOUTH OF GAMBIA FROM 12N TO 14N BETWEEN 14W AND 16W AND IN THE WATER FROM 12N TO 14N BETWEEN 18W AND 20W...ISOLATED MODERATE ELSEWHERE FROM 3N TO 16N TO THE EAST OF 53W. ...DISCUSSION... THE GULF OF MEXICO... A MIDDLE LEVEL TO UPPER LEVEL TROUGH CUTS THROUGH THE FLORIDA PANHANDLE...TO 24N90W TO 19N92W IN THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO. COMPARATIVELY DRIER IN SUBSIDENCE IS TO THE WEST OF THE FLORIDA PANHANDLE-TO-19N92W LINE. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE RAINSHOWERS ARE TO THE EAST OF THE FLORIDA PANHANDLE-TO-19N92W LINE. A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N73W IN THE ATLANTIC OCEAN TO 30N76W. A COLD FRONT PASSES THROUGH 32N69W IN THE ATLANTIC OCEAN...TO A 1015 MB LOW PRESSURE CENTER THAT IS NEAR 28N75W. THE FRONT BECOMES DISSIPATING STATIONARY FROM THE 1015 MB LOW PRESSURE CENTER THAT IS NEAR 28N75W...ON TOP OF THE FLORIDA KEYS...TO 23N87W IN THE GULF OF MEXICO. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE RAINSHOWERS ARE TO THE WEST/NORTHWEST OF THE LINE THAT PASSES THROUGH 32N61W TO 29N62W TO 22N71W. THE CARIBBEAN SEA... SCATTERED MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION IS TO THE NORTHWEST OF THE LINE THAT PASSES THROUGH HONDURAS NEAR 14N88W...BEYOND 20N76W IN SOUTHEASTERN CUBA. THIS PRECIPITATION IS RELATED TO THE UPPER LEVEL DIFFLUENT WIND FLOW FROM THE GULF OF MEXICO FLORID PANHANDLE TO 24N90W TO 19N92W MIDDLE TO UPPER LEVEL TROUGH. A MIDDLE LEVEL TO UPPER LEVEL TROUGH IS ALONG 20N65W 14N70W 10N79W. THIS CYCLONIC WIND FLOW HAS BEEN IN THE CARIBBEAN SEA FOR AT LEAST THE LAST 4 DAYS OR MORE. THE CYCLONIC CIRCULATION CENTER FROM 24 HOURS AGO HAS WEAKENED AND DISSIPATED. CONVECTIVE PRECIPITATION...SCATTERED TO NUMEROUS STRONG FROM VENEZUELA COAST TO 11N BETWEEN 67W AND 69W AND JUST NORTH OF LAKE MARACAIBO IN VENEZUELA WITHIN A 15 TO 30 NM RADIUS OF 11N72W...SCATTERED MODERATE TO ISOLATED STRONG FROM 13N TO 16N BETWEEN 62W AND 66W...ISOLATED MODERATE ELSEWHERE TO THE EAST OF THE LINE 20N64W 16N71W 14N71W 11N77W. THE MONSOON TROUGH IS ALONG 9N/10N BETWEEN 75W IN COLOMBIA AND 88W IN THE EASTERN PACIFIC OCEAN. RAINSHOWERS ARE POSSIBLE IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA TO THE SOUTH OF 12N TO THE WEST OF 77W. PLEASE READ THE HIGH SEAS FORECASTS...MIAHSFAT2...AND THE OFFSHORE FORECAST...MIAOFFNT3...FOR DETAILS ABOUT 20 TO 25 KNOT WINDS AND 8 FOOT SEA HEIGHTS FROM 12N TO 16N BETWEEN 71W AND 78W FOR AT LEAST THE FIRST 24 HOURS OF THE FORECAST PERIOD. THE ATLANTIC OCEAN... AN UPPER LEVEL TROUGH PASSES THROUGH 32N58W TO A 25N58W CYCLONIC CIRCULATION CENTER...TO 20N58W. ISOLATED MODERATE TO LOCALLY STRONG CONVECTIVE PRECIPITATION TO THE NORTH OF 24N BETWEEN 57W AND 59W. A SURFACE TROUGH IS ALONG 23N47W 20N50W 18N51W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION IS FROM 21N TO 22N BETWEEN 48W AND 49W. A DEEP LAYER TROUGH EXTENDS AWAY FROM THE AREA THAT IS NEAR TROPICAL STORM NADINE...TO 27N30W 22N36W 17N42W 11N43W. COMPARATIVELY DRIER AIR IN SUBSIDENCE SPANS THE AREA OF THE TROUGH AND IT INCLUDES THE ATLANTIC OCEAN THAT IS TO THE SOUTH OF 30N TO THE EAST OF 30W...AND FROM 15N TO 23N BETWEEN 30W AND 45W. A SURFACE RIDGE PASSES THROUGH 32N53W TO 30N57W AND 21N67W. PLEASE READ THE HIGH SEAS FORECASTS...MIAHSFAT2...FOR DETAILS ABOUT 8 TO 12 FOOT SEA HEIGHTS TO THE NORTH OF 20N TO THE EAST OF 53W AT THE START OF THE FORECAST TIME. TROPICAL STORM NADINE BEGINS TO BE A FACTOR AT 24 HOURS INTO THE FORECAST PERIOD... NEAR 31.5N 30.5W...AND NEAR 29.9N 30.8W AT 48 HOURS INTO THE FORECAST PERIOD. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT