000 AXNT20 KNHC 131052 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU SEP 13 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 THROUGH 1015 UTC. ...SPECIAL FEATURES... TROPICAL STORM NADINE IS CENTERED NEAR 21.0N 50.6W 13/0900 UTC OR ABOUT 695 NM ENE OF THE LESSER ANTILLES MOVING NW AT 14 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 990 MB. MAXIMUM SUSTAINED WIND SPEED IS 60 KT WITH GUSTS TO 75 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 20N-25N BETWEEN 45W-53W. ...TROPICAL WAVES... TROPICAL WAVE IS SW OF THE CAPE VERDE ISLANDS EXTENDING FROM 14N38W TO A 1011 MB LOW NEAR 8N34W MOVING W 15-20 KT. WAVE IS EMBEDDED WITHIN AN AREA OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE FROM 5N-14N BETWEEN 33W-41W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA ENTERING THE E TROPICAL ATLC NEAR 14N16W CONTINUING ALONG 9N21W TO THE 1011 MB LOW/TROPICAL WAVE NEAR 8N34W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 7N-13N E OF 18W TO INLAND OVER W AFRICA AND FROM 5N-8N BETWEEN 19W-25W. ...DISCUSSION... GULF OF MEXICO... THE CUTOFF UPPER LOW REMAINS OVER THE LOWER MISSISSIPPI VALLEY WITH THE UPPER TROUGH EXTENDING S OVER THE N GULF OF MEXICO. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE N OF 27N W OF 83W TO INLAND OVER TEXAS. AN UPPER RIDGE EXTENDS ACROSS SW MEXICO TO OVER THE SW GULF ENHANCING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS FROM 20N-27N W OF 94W TO INLAND OVER MEXICO. A SURFACE TROUGH IS ALONG THE E COAST OF FLORIDA INTO THE STRAITS OF FLORIDA TO THE COAST OF CUBA NEAR 23N81W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 26N E OF 88W TO OVER S FLORIDA AND THROUGH THE STRAITS OF FLORIDA. SURFACE RIDGE CONTINUES TO BUILD S OVER THE N GULF ANCHORED BY A 1027 MB HIGH OVER NORTH CAROLINA. THE REMAINDER OF THE GULF IS UNDER FAIR WEATHER THIS MORNING. HIGH PRESSURE WILL PREVAIL THROUGH THE WEEKEND. CARIBBEAN SEA... A BROAD UPPER RIDGE OVER THE W ATLC DOMINATES THE N CARIBBEAN WHILE A SECOND UPPER RIDGE DOMINATES THE SW WATERS. A SURFACE TROUGH EXTENDS ALONG E COAST OF FLORIDA INTO THE STRAITS OF FLORIDA TO COAST OF CUBA NEAR 23N81W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 21N TO OVER W CUBA AND THROUGH THE YUCATAN CHANNEL BETWEEN 82W-87W. THE MONSOON TROUGH EXTENDS FROM COLOMBIA ALONG 10N ACROSS COSTA RICA INTO THE E PACIFIC REGION GENERATING SCATTERED SHOWERS/THUNDERSTORMS S OF 11N BETWEEN 75W-82W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 11N-14N W OF 82W TO INLAND OVER NICARAGUA. A CUTOFF UPPER LOW IS CENTERED JUST N OF THE VIRGIN ISLANDS EXTENDING AN UPPER TROUGH OVER THE E CARIBBEAN E OF 71W. CLUSTERS OF ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE ACROSS THE NE CARIBBEAN N OF 16N E OF 75W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE IN THE SE CARIBBEAN S OF 13N BETWEEN 61-69W INCLUDING BONAIRE AND CURACAO ISLANDS. MODERATE TO FRESH TRADE WINDS ARE ACROSS THE S CENTRAL CARIBBEAN WATERS WITH LIGHT TO MODERATE TRADE WINDS ELSEWHERE. OTHERWISE THE REMAINDER OF THE CARIBBEAN IS UNDER FAIR WEATHER THIS MORNING. HIGH PRESSURE OVER THE W ATLC WILL MAINTAIN TRADE THROUGH THU. ATLANTIC OCEAN... THE PRIMARY CONCERN THIS MORNING IS TROPICAL STORM NADINE IN THE CENTRAL TROPICAL ATLC. SEE SPECIAL FEATURES ABOVE. AN UPPER RIDGE DOMINATES THE W ATLC ANCHORED OVER THE CENTRAL BAHAMA ISLANDS. A SURFACE RIDGE CONTINUES TO BUILD S OVER THE W ATLC W OF THE FRONTAL BOUNDARY DESCRIBED BELOW AND ANCHORED BY A 1027 MB HIGH OVER NORTH CAROLINA. AN UPPER TROUGH COVERS THE NW ATLC SUPPORTING A STATIONARY FRONT THAT EXTENDS INTO THE CENTRAL ATLC NEAR 32N57W EXTENDING TO A WEAK 1016 MB LOW NEAR 29N64W CONTINUING S ALONG 25N67W THEN W TO THE BAHAMA ISLANDS NEAR 24N77W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 60 NM EITHER SIDE OF THE FRONT. A SURFACE TROUGH HAS DEVELOPED ALONG THE E COAST OF FLORIDA FROM 27N79S INTO THE STRAITS OF FLORIDA TO THE COAST OF CUBA NEAR 23N81W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 27N W OF 78W TO OVER S FLORIDA AND THROUGH THE STRAITS OF FLORIDA. A CUTOFF UPPER LOW IS CENTERED N OF THE VIRGIN ISLANDS NEAR 20N64W EXTENDING AN UPPER TROUGH OVER THE E CARIBBEAN AND NNE TO NEAR 28N59W PRECEDING TROPICAL STORM NADINE GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 24N-32N BETWEEN 52W-58W. BROAD UPPER LOW IS CENTERED OVER THE NE ATLC COVERING THE AREA N OF 23N BETWEEN 15W-40W SUPPORTING SURFACE TROUGH THAT EXTENDS FROM 32N23W TO 26N30W GENERATING CLUSTERS OF SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 45 NM EITHER SIDE OF THE TROUGH AND FROM 26N-29N BETWEEN 31W-35W. HIGH PRESSURE WILL WILL WEAKEN THROUGH THE WEEKEND. TROPICAL STORM NADINE OVER THE CENTRAL TROPICAL ATLC IS FORECAST TO REACH HURRICANE INTENSITY BY THIS AFTERNOON WHILE MAINTAINING A NW TRACK AND IS FORECAST TO REMAIN IN THE CENTRAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW