000 AXNT20 KNHC 271111 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU SEP 27 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY VALID THROUGH 1015 UTC. ...SPECIAL FEATURE... THE CENTER OF TROPICAL STORM NADINE AT 26/0900 UTC IS NEAR 28.9N 31.5W. NADINE IS ABOUT 590 NM/1095 KM TO THE SOUTH- SOUTHWEST OF THE AZORES. NADINE IS MOVING SOUTHWESTWARD 5 KNOTS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 992 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 50 KNOTS WITH GUSTS TO 60 KNOTS. TROPICAL STORM FORCE WINDS EXTEND AWAY FROM THE CENTER OF NADINE AS FAR AS 110 NM IN THE NORTHEASTERN QUADRANT...60 NM IN THE SOUTHEASTERN QUADRANT...80 NM IN THE SOUTHWESTERN QUADRANT...AND TO 120 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 STRONG FROM 28N TO 31N BETWEEN 30W AND 33W. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 31W/32W TO THE SOUTH OF 17N MOVING WESTWARD 15 KNOTS DURING THE LAST 24 HOURS. THIS POSITION IS BASED ON STUDYING LONG-TERM SATELLITE IMAGERY. RAINSHOWERS ARE POSSIBLE FROM 8N TO 17N BETWEEN 30W AND 35W. A CARIBBEAN SEA TROPICAL WAVE IS ALONG 74W/75W...FROM SOUTHEASTERN CUBA IN THE WINDWARD PASSAGE TO COASTAL COLOMBIA. THE WAVE IS MOVING WESTWARD 15 KNOTS DURING THE LAST 24 HOURS. THE TROPICAL WAVE IS JUST TO THE EAST OF AN UPPER LEVEL TROUGH THAT PASSES THROUGH THE WINDWARD PASSAGE TO A 13N75W CYCLONIC CIRCULATION CENTER TO THE GULF OF URABA OF COLOMBIA. 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. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SENEGAL NEAR 14N17W TO 9N30W 8N40W. THE ITCZ CONTINUES FROM 8N40W TO 7N51W. CONVECTIVE PRECIPITATION...SCATTERED TO NUMEROUS STRONG WITHIN 60 NM ON EITHER SIDE OF 7N12W 6N15W 5N19W...SCATTERED STRONG FROM 14N TO 18N BETWEEN 23W AND 30W...BROKEN TO OVERCAST MULTILAYERED CLOUDS AND WIDELY SCATTERED MODERATE TO ISOLATED STRONG ELSEWHERE TO THE SOUTH OF 18N TO THE EAST OF 47W. ...DISCUSSION... THE GULF OF MEXICO... BROAD AND LARGE-SCALE UPPER LEVEL ANTICYCLONIC WIND FLOW MOVES ACROSS MEXICO...FROM THE EASTERN PACIFIC OCEAN AND TROPICAL STORM NADINE...INTO THE WESTERN HALF OF THE GULF OF MEXICO. THE ANTICYCLONIC WIND FLOW IS PUSHING HIGH LEVEL MOISTURE ACROSS MEXICO...INTO THE GULF OF MEXICO TO THE WEST OF 90W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION IS TO THE SOUTH OF 28N TO THE WEST OF 87W. THE REMAINS OF A MIDDLE LEVEL TO UPPER LEVEL TROUGH ARE MOVING THROUGH THE EASTERN SECTION OF THE AREA. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND ISOLATED MODERATE CONVECTIVE PRECIPITATION ARE TO THE SOUTH OF 27N TO THE EAST OF 87W. THE FRONTAL BOUNDARY THAT WAS CUTTING ACROSS THE BAHAMAS INTO THE FLORIDA STRAITS HAS WEAKENED AND DISSIPATED. A SURFACE RIDGE PASSES THROUGH ALABAMA...THROUGH THE SOUTHEASTERN HALF OF LOUISIANA...TOWARD THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO. THE CARIBBEAN SEA... AN UPPER LEVEL TROUGH PASSES THROUGH THE WINDWARD PASSAGE TO A 13N75W CYCLONIC CIRCULATION CENTER TO THE GULF OF URABA OF COLOMBIA. A TROPICAL WAVE IS ALONG 74W/75W...FROM SOUTHEASTERN CUBA IN THE WINDWARD PASSAGE TO COASTAL COLOMBIA. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND ISOLATED MODERATE CONVECTIVE PRECIPITATION COVER THE CARIBBEAN SEA AND THE SOUTHERN BAHAMAS FROM THE COLOMBIA COASTAL WATERS TO 23N IN THE ATLANTIC OCEAN BETWEEN 70W AND 81W. STRONG CONVECTIVE PRECIPITATION IS IN ONE CLUSTER FROM 11N TO 12N BETWEEN 80W AND 81W. ISOLATED MODERATE CONVECTIVE PRECIPITATION IS IN THE NICARAGUA COASTAL WATERS. THE SOUTHERN END OF AN UPPER LEVEL TROUGH PASSES THROUGH THE YUCATAN CHANNEL...INTO THE NORTHWESTERN CORNER OF THE AREA. SCATTERED MODERATE TO ISOLATED STRONG CONVECTIVE PRECIPITATION IS ALONG THE COAST OF THE YUCATAN PENINSULA AND BELIZE...AND IN THE HONDURAS COASTAL WATERS. THE PRECIPITATION ALSO IS TAKING PLACE IN AN AREA OF UPPER LEVEL DIFFLUENT WIND FLOW BETWEEN THE 13N75W CYCLONIC CENTER AND THE TROUGH. THE MONSOON TROUGH IS ALONG 8N73W...THROUGH 8N81W IN PANAMA... BEYOND SOUTHERN COSTA RICA. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO STRONG IN COLOMBIA FROM 5N TO 8N BETWEEN 73W AND 77W. THE ATLANTIC OCEAN... AN UPPER LEVEL TROUGH EXTENDS FROM A 30N47W CYCLONIC CIRCULATION CENTER TO 25N49W...TO A 20N55W CYCLONIC CIRCULATION CENTER... WESTWARD TO THE MONA PASSAGE THAT IS BETWEEN PUERTO RICO AND HISPANIOLA. COMPARATIVELY DRIER AIR IN SUBSIDENCE IS BETWEEN THE 20N55W CYCLONIC CENTER AND THE MONA PASSAGE FROM 14N TO 23N. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG WITHIN 60 TO 90 NM ON EITHER SIDE OF 25N45W 21N57W. A SURFACE TROUGH IS ALONG 23N52W 19N54W 16N54W. WIDELY SCATTERED TO SCATTERED MODERATE FROM 11N TO 17N BETWEEN 48W AND 60W. A 1015 MB HIGH PRESSURE CENTER IS NEAR 25N24W. SURFACE ANTICYCLONIC WIND FLOW IS WITHIN 180 NM OF THE CENTER IN THE NORTHERN SEMICIRCLE...AND WITHIN 240 NM OF THE CENTER IN THE SOUTHERN SEMICIRCLE. A SECOND SURFACE RIDGE EXTENDS FROM 1027 MB HIGH PRESSURE CENTER THAT IS NEAR 39N46W TO 30N42W AND 20N37W. PLEASE READ THE HIGH SEAS FORECASTS...MIAHSFAT2... FOR DETAILS ABOUT TROPICAL STORM NADINE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT