000 AXPZ20 KNHC 260250 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SAT OCT 26 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 0230 UTC. ...SPECIAL FEATURE... TROPICAL STORM RAYMOND IS CENTERED AT 12.9N 110.8 AT 26/0300 UTC OR ABOUT 695 SM S OF THE SOUTHERN TIP OF BAJA CALIFORNIA. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SCATTERED MODERATE TO STRONG CONVECTION SURROUNDS RAYMOND WITHIN 90 NM EITHER SIDE OF A LINE FROM 14N109.5W TO 11N113W. RAYMOND IS MOVING WSW...OR 245 DEG AT 9 T...AND IS EXPECTED TO CONTINUE ON A GENERAL WSW TRACK AROUND THE PERIPHERY OF AN UPPER RIDGE FOR THE NEXT FEW DAYS. ATMOSPHERIC AND OCEANIC CONDITIONS SUGGEST RAYMOND WILL STRENGTHEN SLIGHTLY OVER THE NEXT COUPLE OF DAYS...AND THAT STRENGTHENING IS REFLECTED IN THE OFFICIAL FORECAST THAT BEGINS TO WEAKEN RAYMOND TO A TROPICAL STORM AGAIN LATE MON. 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 E TO W ACROSS THE SW CARIBBEAN BETWEEN 09-10N FROM THE NW COAST OF COLOMBIA AT 09N76W TO ACROSS CENTRAL COSTA RICA TO THE PACIFIC COAST OF COSTA RICA AT 10N85W...THEN CONTINUES W TO 10N96W...THEN TURNS NW TO 14N103W 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 11N115W AND CONTINUES SW THROUGH AN EMBEDDED 1011 MB LOW PRESSURE AT 10N116.5W...THEN SW TO 08N124W...THEN NW THROUGH AN EMBEDDED 1011 MB LOW PRESSURE AT 09N130W...THEN WSW TO BEYOND 08N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION HAS MOVED OVER AND WITHIN 45 NM OF THE COAST OF CENTRAL AMERICA FROM THE GULF OF PANAMA NW TO THE COAST OF GUATEMALA. SIMILAR CONVECTION IS NOTED WELL S OF THE EASTERN SEGMENT OF THE MONSOON TROUGH WITHIN 45 NM OF 07N89W...AND WITHIN 60 NM EITHER SIDE OF A LINE FROM 13N93W TO 09N101W. ...DISCUSSION... THE UPPER LEVEL CYCLONE IS N OF THE AREA NEAR 37N132W... TRAILING AN UPPER TROUGH SW INTO THE AREA ALONG 32N130W TO 26N140W. UPPER MOISTURE THAT ORIGINATED W OF THE DISCUSSION AREA IS STREAMING NE ACROSS THE DISCUSSION AREA WITHIN 90 NM EITHER SIDE OF A LINE FROM 21N140W TO 32N122W...AND IS CURRENTLY FANNING OUT ACROSS SOUTHERN CALIFORNIA. AN ASSOCIATED SURFACE FRONTAL TROUGH EXTENDS FROM 32N128W TO 26N140W...BUT IS ACCOMPANIED BY ONLY A 5-10 KT SW-NW WIND SHIFT WITHIN THE DISCUSSION AREA. NW SWELL W OF THE FRONTAL TROUGH HAS SUBSIDED WITH COMBINED SEAS NOW AT A MAX OF 7 FT. THE FRONTAL TROUGH WILL MOVE SLOWLY E AND GRADUALLY DISSIPATE OVER THE NEXT DAY OR SO. THE UPPER CYCLONE IS EXPECTED TO MOVE SE TO NEAR 35N130W ON SAT MAINTAINING SOUTHWESTERLY UPPER FLOW ACROSS THE SUBTROPICS TO THE W OF 120W...AND NEARLY ZONAL FLOW TO THE E OF 120W OVER THE NEXT FEW DAYS. AN UPPER ANTICYCLONE IS STATIONARY NEAR TROPICAL CYCLONE RAYMOND AT 17N104W WITH AN UPPER RIDGE EXTENDING SW TO A SHARP CREST OVER THE DEEP TROPICS AT 08N138W. THE WESTERN EXTENT OF THIS RIDGE IS ALREADY BEGINNING TO RETRACT EASTWARD...WHILE THE NEARLY STATIONARY EASTERN PORTION OF THE RIDGE CONTINUES TO STEER TROPICAL CYCLONE RAYMOND WESTWARD. THE ASSOCIATED UPPER DIFFLUENCE ALONG THE RIDGE AXIS IS ROUGHLY IN PHASE WITH THE WESTERN SEGMENT OF THE LOWER LEVEL MONSOON TROUGH...AND ITS EMBEDDED SURFACE LOW AT 09N130W...AND IS ENHANCING THE CONVECTION PREVIOUSLY DESCRIBED. THE RESULTANT DEBRIS MOISTURE IS ADVECTED NE ALONG THE NW PERIPHERY OF THE UPPER RIDGE... CONCENTRATING INTO A NARROW TROPICAL PLUME THAT IS CURRENTLY EVAPORATING NEAR 21N121W. UPPER MOISTURE FROM TROPICAL CYCLONE RAYMOND IS STREAMING E ACROSS CENTRAL OLD MEXICO BETWEEN 19- 25N...AND MERGES WITH ADDITIONAL MOISTURE FROM DECAYING CONVECTION OVER THE BAY OF CAMPECHE...WITH THE MOISTURE CONTINUING ENE ACROSS THE SE GULF OF MEXICO...THE FLORIDA STRAITS AND ACROSS THE BAHAMAS. AN INVERTED UPPER TROUGH IS NOTED OVER THE DEEP TROPICS TO THE S OF 09N BETWEEN 90-110W. AN UPPER RIDGE EXTENDS E FROM THE ANTICYCLONE ASSOCIATED WITH TROPICAL CYCLONE RAYMOND TO A GENTLE CREST OVER THE NW CARIBBEAN AT 15N75W. THE ANTICYCLONIC ENVELOPE EXTENDS S ACROSS THE UPPER LEVELS OF THE DISCUSSION AREA GENERALLY TO THE N OF 09N AND W OF 75W. THE ASSOCIATED UPPER DIFFLUENCE PREVIOUSLY ENHANCED CONVECTION OVER MOST OF CENTRAL AMERICA...THE WESTERN CARIBBEAN...AND OVER THE TROPICAL PACIFIC ALONG THE EASTERN SEGMENT OF THE MONSOON TROUGH AS PREVIOUSLY MENTIONED. MOST OF THE UPPER DEBRIS REMAINS TRAPPED WITH THE ANTICYCLONIC ENVELOPE. GULF OF TEHUANTEPEC GAP WIND EVENT...CURRENT SURFACE DATA OVER THE SW GULF OF MEXICO SUGGESTS THAT THE NORTHERLY FLOW WILL SURGE THROUGH THE ISTHMUS OF TEHUANTEPEC AT 20-30 KT...SEAS 9-13 FT...THROUGH SUNRISE ON SAT THEN DIMINISH. EXPECT LATE PULSES OF 20-25 KT THROUGH SUN NIGHT. GUIDANCE THEN SUGGESTS THE DRAINAGE FLOW WILL ONLY BE AT 15-20 KT LATE MON NIGHT THROUGH SUNRISE ON TUE. $$ NELSON