000 AXPZ20 KNHC 230254 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC WED OCT 23 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 ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0315 UTC. ...SPECIAL FEATURES... HURRICANE RAYMOND IS CENTERED AT 16.2N 101.8W AT 23/0000 UTC OR ABOUT 105 NM S OF ZIHUATANEJO MEXICO...AND ABOUT 135 NM WSW OF ACAPULCO MEXICO. ESTIMATED MINIMUM CENTRAL PRESSURE IS 987 MB. MAXIMUM SUSTAINED WIND SPEED IS 65 KT WITH GUSTS TO 80 KT. CURRENTLY SCATTERED MODERATE ISOLATED STRONG CONVECTION IS FAIRLY CONCENTRIC WITHIN 150 NM OF CENTER. RAYMOND HAS BEEN NEARLY STATIONARY OVER THE PAST SEVERAL HOURS...BUT IS EXPECTED TO BEGIN DRIFTING IN A GENERALLY WSW DIRECTION AND CONTINUE TO ENCOUNTER SOUTHERLY SHEAR WHICH SHOULD WEAKEN RAYMOND BELOW HURRICANE STRENGTH LATE WED. HEAVY RAINFALL CONTINUES TO BE THE MAIN THREAT OVER...AND JUST INLAND THE MEXICAN COAST...FROM 99W- 104W...WHERE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES COULD OCCUR. ALTHOUGH THE MAXIMUM SEAS ARE GRADUALLY SUBSIDING...LARGE SEAS WILL CONTINUE ALONG THE CENTRAL PACIFIC COAST FOR THE NEXT SEVERAL DAYS. SEE THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPEP2/WTPZ32 KNHC...AND THE FULL FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM SE TO NW ACROSS THE SW CARIBBEAN FROM THE NW COAST OF COLOMBIA AT 08.5N77W TO ALONG THE CARIBBEAN COAST OF PANAMA...TURNING W AT 10N80W TO ACROSS COSTA RICA TO THE PACIFIC COAST OF COSTA RICA AT 10N86W...CONTINUING W TO 10N88W...THEN NW TO 15N97W WHERE IT LOSSES IDENTITY IN THE BROAD CYCLONIC CIRCULATION ASSOCIATED WITH TROPICAL CYCLONE RAYMOND. SCATTEROMETER WINDS INDICATE THAT THE MONSOON TROUGH RESUMES SW OF TROPICAL CYCLONE RAYMOND AT 13N109W...THEN CONTINUES SW TO 10N120W...THEN W TO 11N134W...THEN SW TO BEYOND 07N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED OVER THE COASTAL PACIFIC WATERS OF COSTA RICA WITHIN 45 NM EITHER SIDE OF A LINE FROM 06N81W TO 09N85W. SIMILAR CONVECTION IS NOTED WELL S OF TROPICAL CYCLONE RAYMOND...WITHIN 75 NM OF 11N103W...AND ALONG THE WESTERN SEGMENT OF THE MONSOON TROUGH WITHIN 120 NM EITHER SIDE OF LINES FROM 11N116W TO 09N125W TO 10N131W...AND FROM 14N134W TO 08N136W. ...DISCUSSION... AN UPPER CYCLONE IS CENTERED AT 33N125W WITH AN UPPER TROUGH EXTENDING SW IN THE AREA ALONG 28N130W TO 10N138W TO A BASE OVER THE DEEP TROPICS AT 04N137W. SOME UPPER MOISTURE IS ROTATING E THROUGH THE UPPER TROUGH ACROSS THE SUBTROPICS N OF 23N...WITH THE MOISTURE PROGRESSING E AS THE UPPER FLOW BECOMES ZONAL TO THE N OF 20N BETWEEN 125-110W. THE MOISTURE WILL PASS ACROSS THE CENTRAL BAJA CALIFORNIA PENINSULA LATE TONIGHT. A STATIONARY SURFACE FRONT IS ANALYZED N OF 24N ALONG 141W WITH SOUTHERLY FLOW AT 15-20 KT OVER THE DISCUSSION AREA N OF 23N W OF 135W...WITH SEAS 6-8 FT. THE UPPER CYCLONE IS EXPECTED TO MOVE NW AND GRADUALLY FILL OVER THE NEXT FEW DAYS...BUT TRAIL AN UPPER TROUGH SW ACROSS THE WESTERN PORTION OF THE DISCUSSION AREA. THE SURFACE FRONT WILL BEGIN TO MOVE E AS A COLD FRONT AND INTO THE AREA WED...REACHING FROM 32N132W TO 25N140W ON THU...AND FROM 32N128W TO 25N138W ON FRI...BUT THE GRADIENT WILL WEAKEN AND ONLY SUPPORT A 10-15 KT WIND SHIFT AFTER SUNRISE ON WED. AN UPPER ANTICYCLONE IS QUASI-STATIONARY AT 12N111W WITH AN UPPER RIDGE EXTENDING W TO A CREST AT 12N131W...AND IS EXPECTED TO CHANGE LITTLE OVER THE NEXT COUPLE OF DAYS REMAINING THE DOMINANT UPPER FEATURE OVER THE TROPICS. ASSOCIATED UPPER DIFFLUENCE ALONG THE RIDGE AXIS IS IN PHASE WITH THE WESTERN SEGMENT OF THE MONSOON TROUGH...AND IS ENHANCING THE CONVECTION PREVIOUSLY DESCRIBED. SOME OF THE DEBRIS MOISTURE IS ADVECTED NE ALONG THE NW PERIPHERY OF THE UPPER RIDGE TO NEAR 18N122W WHERE IT IS CURRENTLY EVAPORATING. AN UPPER RIDGE ALSO EXTENDS E FROM THE ANTICYCLONE TO A CREST AT 14N107W. A SECOND UPPER ANTICYCLONE IS CENTERED OVER THE NORTHERN YUCATAN PENINSULA AT 21N89W WITH ITS ANTICYCLONIC ENVELOPE DOMINATING THE DISCUSSION AREA N OF 05N TO THE E OF 98W. ASSOCIATED UPPER DIFFLUENCE ENHANCED CONSIDERABLE CONVECTION OVER THE SW CARIBBEAN AND HAS NOW MOVED OVER CENTRAL AMERICA BETWEEN 82-88W... WITH THE RESULTANT DENSE DEBRIS MOISTURE SPREADING W OVER THE DISCUSSION AREA N OF 05N AND E OF 88W. TROPICAL CYCLONE RAYMOND IS CENTERED TO THE W CREST OF THIS ANTICYCLONE...AND TO E OF THE UPPER RIDGE PREVIOUSLY MENTIONED...THUS THE NEARLY STATIONARY MOTION FOR RAYMOND. SOME OF THE DENSE DEBRIS MOISTURE FROM RAYMOND IS ADVECTED NE ACROSS CENTRAL MEXICO...DISSECTING THE GULF OF MEXICO FROM SW TO NE...AND CONTINUING ACROSS THE SE CONUS...AND FEEDING INTO CONVECTION ASSOCIATED WITH A FRONTAL TROUGH OVER THE SE GULF OF MEXICO AND NOW OVER CENTRAL FLORIDA. ELSEWHERE AT THE SURFACE...A RIDGE IS NOTED N OF 18N BETWEEN 110- 130W. NE TRADES AT 15-20 KT...SEAS 6-9 FT ARE OBSERVED FROM 11- 21N W OF 130W. THE EFFECTED AREA WILL GRADUALLY SHRINK TO 12-14N BETWEEN 138W-140W ON THU. GULF OF TEHUANTEPEC...NORTHERLY DRAINAGE WINDS ARE EXPECTED TO SURGE AT 15-20 KT INTO THE NORTHERN GULF OF TEHUANTEPEC LATE TUE NIGHT...THEN GRADUALLY INCREASE TO 20-30 KT BY WED EVENING... WITH THESE CONDITIONS SPREADING AS FAR S AS 13N98W ON THU...AND NEAR 11N97W LATE FRI. GUIDANCE CURRENTLY DOES NOT SUGGEST A GALE EVENT...BUT DOES INDICATE THE NEAR GALE 30 KT WINDS CONTINUING THROUGH SUNRISE SAT...THEN DIMINISHING TO 25 KT AT SUNRISE ON SUN. $$ NELSON