000 AXPZ20 KNHC 260340 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC THU NOV 26 2015 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 FEATURES... HURRICANE SANDRA WAS CENTERED NEAR 13.6N 110.4W AT 0300 UTC...OR ABOUT 465 NM SW OF MANZANILLO MEXICO AND ABOUT 550 NM S OF THE SOUTHERN TIP OF THE BAJA CALIFORNIA PENINSULA. SANDRA IS MOVING NW OR 320 DEGREES AT 7 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE WAS 959 MB. MAXIMUM SUSTAINED WINDS ARE NOW 105 KT WITH GUSTS TO 130 KT...MAKING SANDRA A DANGEROUS CATEGORY THREE HURRICANE. SOME ADDITIONAL STRENGTHENING OF SANDRA IS POSSIBLE TONIGHT AS IT MOVES NORTHWARD AND REMAINS OVER WARM WATERS. CURRENTLY NUMEROUS STRONG CONVECTION IS OCCURRING IN SOLID BANDS WITHIN 60 NM NE AND 30 NM SW SEMICIRCLES...WHILE SCATTERED MODERATE TO STRONG CONVECTION IS OCCURRING IN BANDS ELSEWHERE WITHIN 400 NM NE AND 120 NM SW SEMICIRCLES. SANDRA IS FORECAST TO TURN TOWARD THE NORTH NORTHEAST THURSDAY AND ACCELERATE TOWARD THE SOUTHERN PORTIONS OF THE GULF OF CALIFORNIA AND BAJA CALIFORNIA PENINSULA...AND LOCAL INTERESTS SHOULD MONITOR THE PROGRESS OF SANDRA AS WATCHES AND WARNINGS MAY BE REQUIRED LATER TONIGHT. MARINE CONDITIONS ACROSS THE PACIFIC WATERS OF BAJA CALIFORNIA SUR WILL DETERIORATE RAPIDLY THURSDAY THROUGH AND FRIDAY AS SOUTHEAST SWELL FROM SANDRA BEGINS TO MERGE WITH LONG PERIOD NORTHERLY SWELL MOVING INTO THE AREA FROM THE NORTHEAST PACIFIC. SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS. GULF OF TEHUANTEPEC GALE WARNING...NORTHERLY WINDS BLOWING ACROSS THE GULF OF TEHUANTEPEC REMAIN AT 20-30 KT THIS EVENING...BUT ARE EXPECTED TO BRIEFLY INCREASE TONIGHT TO MINIMAL GALE FORCE DURING THE MAXIMUM NOCTURNAL DRAINAGE PERIOD...LATE TONIGHT THROUGH SUNRISE ON THU. ALTHOUGH THE PRESSURE GRADIENT WILL GRADUALLY WEAKEN ACROSS SOUTHERN MEXICO OVER THE NEXT SEVERAL DAYS...THE MAXIMUM DRAINAGE FLOW SHOULD REACH AROUND 30 KT EACH OF THE NEXT SEVERAL NIGHTS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM LOW PRES 1006 MB NEAR 10N74.5W TO 07.5N94W TO 09N100W...WHERE IT REMAINS FRACTURED...THEN RESUMES FROM 09N111W TO 03N119W...WHERE IT TRANSITIONS TO ITCZ... CONTINUING ON TO 02N140W. SCATTERED MODERATE TO STRONG WITHIN 180 NM SE OF TROUGH E OF 112W. ...DISCUSSION... A COLD FRONT ENTERS THE DISCUSSION AREA AT 30N115W AND EXTENDS THROUGH 26.5N125W TO 30N138W. NORTHERLY WINDS AT 15-20 KT ACCOMPANY THE FRONT TO THE S OF 32N...WITH LONG PERIOD NW SWELL MOVING INTO THE AREA AND OUTRUNNING THE COLD FRONT DURING THE NEXT 48 HOURS. SEAS TO 8-10 FT IN NW TO N SWELL CURRENTLY PREVAIL TO THE N OF THE FRONT. ALTHOUGH THE FRONT IS EXPECTED TO CONTINUE S AND BECOME ILL DEFINED BY LATE THU...THE PRESSURE GRADIENT WITHTHE FRONT WILL TIGHTEN...INCREASING THE NE FLOW TO 20-25 KT ACROSS THE WATERS FROM 19-23N BETWEEN 122-132W. BY THEN THE LONG PERIOD NW SWELL WILL PROPAGATE S ACROSS THE DISCUSSION WATERS N OF 18N W OF 118W BY LATE THU WITH SEAS BUILDING TO 8-11 FT. AS MENTIONED ABOVE...THE NW SWELL WILL MIX WITH THE BROAD MIX OF SOUTHEASTERLY SWELL ASSOCIATED WITH TROPICAL CYCLONE SANDRA ON THU THROUGH FRI ACROSS THE WATERS FROM ABOUT 13-27N BETWEEN 112-120W. A 1010 MB LOW IS ANALYZED AT 21N125W...AND IS THE REMNANTS OF TROPICAL CYCLONE RICK. BROKEN TO LOCALLY OVERCAST STRATO CUMULUS CLOUDS PREVAIL UP TO 240 NM ACROSS THE N SEMICIRCLE OF THE CENTER. ALTHOUGH THE LOW IS FORECAST TO OPEN UP TO A TROUGH TONIGHT...HIGH PRESSURE BUILDING SOUTHWARD INTO THE REGION WITH THE COLD FRONT HAS INCREASED THE PRESSURE GRADIENT TO THE N AND NW OF THE TROUGH TONIGHT...PRODUCING AN AREA OF NE WINDS 20-25 KT FROM 21.5N TO 24N BETWEEN 125W AND 129W...WHERE SEAS ARE RUNNING 7-9 FT. THESE WINDS AND SEAS WILL GRADUALLY BE OVERRUN BY THE WINDS AND SEAS ASSOCIATED WITH THE COLD FRONT ON THU. GAP WINDS... GULF OF PAPAGAYO...A TIGHT PRESSURE GRADIENT WILL CONTINUE TO SUPPORT PULSES OF NE-E 20-25 KT WINDS TONIGHT AND AGAIN ON THU NIGHT WITH SEAS BUILDING TO 8 FT DOWNSTREAM OF THE GULF OF PAPAGAYO TO NEAR 09N90W. $$ STRIPLING