000 AXPZ20 KNHC 132235 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC THU SEP 12 2013 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2115 UTC. ...SPECIAL FEATURE... THE SMALL LOW PRESSURE CENTER EMBEDDED ALONG THE MONSOON TROUGH OFF THE MEXICAN COAST HAS CONTINUED TO BECOME BETTER ORGANIZED...AND HAS BEEN UPGRADED TO TROPICAL STORM MANUEL... LOCATED NEAR 15.6N 102.1W 998 MB AT 2100 UTC MOVING WNW OR 295 DEG AT 5 KT. MAXIMUM SUSTAINED WINDS 35 KT GUSTS 45 KT. TROPICAL STORM FORCE WINDS EXTEND OUT ONLY TO 20 NM ACROSS E SEMICIRCLE AND 0 NM W SEMICIRCLE. NUMEROUS STRONG CONVECTION WAS WITHIN 60 NM NE AND 90 NM SW SEMICIRCLES...WHILE SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS OCCURRING ELSEWHERE WITHIN 120 NM SE SEMICIRCLE. AN ELONGATED LOW TO MIDDLE LEVEL CYCLONIC GYRE EXTENDS FROM THE SW GULF OF MEXICO...SW ACROSS SOUTHERN MEXICO AND INTO THE EPAC NEAR 10N110W. BOTH TROPICAL STORM MANUEL AND TROPICAL STORM INGRID...IN THE BAY OF CAMPECHE...ARE EMBEDDED WITHIN THIS ELONGATED CIRCULATION...WHICH IS FORECAST TO LIFT NORTHWARD DURING THE NEXT FEW DAYS. TROPICAL STORM MANUEL WILL REMAIN PART OF THIS BROADER CIRCULATION AND IS EXPECTED TO MOVE NORTH TO NORTH-NORTHWESTWARD AND INLAND ACROSS COASTAL MEXICO SUNDAY MORNING. ABUNDANT MOISTURE WITHIN THE ELONGATED GYRE WILL PRODUCE WIDESPREAD SHOWERS AND TSTORMS ACROSS SOUTHEAST AND CENTRAL PORTIONS OF MEXICO DURING THE NEXT FEW DAYS...AND WILL EXACERBATED BY TROPICAL STORM MANUEL. HEAVY RAINS ASSOCIATED WITH MANUAL COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES SAT NIGHT AND SUNDAY. PLEASE SEE WMO HEADER/AWIPS HEADERS WTPZ23 KNHC/MIATCMEP3 FOR ADDITIONAL DETAILS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH EXTENDS FROM COLOMBIA NEAR 06.5N74W TO 13N84W TO 18N90W WHERE IT FRACTURES...THEN RESUMES NEAR 18N98W TO TROPICAL STORM MANUEL TO 15N105W TO 13N120W TO 10N133W TO 09.5N138W... WHERE IT TRANSITIONS TO ITCZ...CONTINUING ON BEYOND 10N140W. SCATTERED MODERATE ISOLATED STRONG FROM 03N TO 08N E OF 79W AND ELSEWHERE FROM 11N TO 18N BETWEEN 92W AND 112W...AND WITHIN 90 NM OF 12N124W. ...DISCUSSION... A BLOCKING TROUGH-RIDGE-TROUGH PATTERN PERSISTS ACROSS THE AREA THIS AFTERNOON...N OF 20N AND W OF 110W...WITH THE RIDGE EXTENDING EWD AND UNDERNEATH THE EASTERN-MOST TROUGH...LOCATED ACROSS THE WRN U.S....AND EXTENDS NE INTO NW MEXICO. A TUTT LOW WAS SHIFTING SLOWLY WWD ACROSS EXTREME S TEXAS AND INTO N CENTRAL MEXICO...AND PRODUCING UPPER CONVERGENCE AND SINKING MOTION TO ITS S TO 19N ACROSS MEXICO. WIDESPREAD CONVECTION OCCURRING WITHIN AND ALONG THE PERIPHERY OF THE CYCLONIC GYRE ACROSS SE MEXICO IS OCCURRING UNDER A LIGHTLY SHEARED ENVIRONMENT...WITH THE PERSISTENT PULSING DEEP CONVECTION MAINTAINING A DIVERGENT UPPER PATTERN AND GENERAL ANTICYCLONIC OUTFLOW ACROSS THE REGION E OF 110W. ELSEWHERE AT LOWER LEVELS...A WEAK 1018 MB SURFACE HIGH WAS CENTERED NEAR 29N132W AND WILL DRIFT SW AND COLLAPSE IN THE NEXT 24-36 HOURS. THE MONSOON CIRCULATION AT LOW LEVELS REMAINS WELL ESTABLISHED...WITH AFTERNOON SCATTEROMETER PASSES INDICATING A LARGE SWATH OF SW TO S WINDS ABOUT 300 NM WIDE EXTENDS FROM THE MEXICAN COASTLINE E OF MANUEL TO NEAR 10N110W. A RATHER LARGE ZONE OF 25-30 KT WINDS WAS INDICATED WITHIN THIS AREA WHERE SEAS ARE BUILDING TO AROUND 15 FT THIS AFTERNOON. THIS LONG FETCH OF STRONG SW WINDS WILL CONTINUE OVER THE NEXT FEW DAYS AND SHIFT SLOWLY N WITH WITH THE MONSOON TROUGH...AND CONTINUE TO GENERATE HIGH AND CONFUSED SEAS SPREADING NORTHEASTWARD INTO THE COASTS AND COASTAL WATERS FROM GUATEMALA NW TO SOUTHERN MEXICO. $$ STRIPLING