000 AXPZ20 KNHC 170948 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC TUE DEC 17 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC...GALE CONDITIONS OF 30-40 KT ARE EXPECTED TO PERSIST THROUGH MID MORNING TODAY THEN DIMINISH TO MINIMAL GALE FORCE OF 30-35 KT THIS AFTERNOON THROUGH EARLY WED NIGHT. THE MAXIMUM DRAINAGE WINDS SHOULD REACH 30 KT LATE WED NIGHT THROUGH SUNRISE THU...AND MAX AT 10-15 KT LATE THU NIGHT THROUGH EARLY FRI MORNING. THE MAXIMUM SEAS ARE CURRENTLY 16 FT DOWNSTREAM OF THE GULF OF TEHUANTEPEC AND WILL GRADUALLY SUBSIDE TO LESS THAN 8 FT ON THU AFTERNOON. THE RESULTANT PLUME OF NE SWELL CONTINUES TO MIX WITH CROSS-EQUATORIAL SW SWELL AND LONG PERIOD NW WITH COMBINED SEAS 8 FT OR GREATER CURRENTLY REACHING ALONG 05N BETWEEN 93-108W. THESE SEAS SHOULD GRADUALLY SUBSIDE TO LESS THAN 8 FT BY LATE THU. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS W FROM THE COLOMBIAN COAST AT 08N77W ACROSS CENTRAL PANAMA AND SOUTHERN COSTA RICA TO THE PACIFIC COAST OF COSTA RICA AT 09N84W...THEN DIPS SW TO 07N92W THEN W TO 07N102W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ. THE ITCZ THEN CONTINUES WESTWARD TO BEYOND 08N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS FLARING ALONG THE MONSOON TROUGH AND ITCZ WITHIN 120 NM EITHER SIDE OF LINES FROM 09N93W TO 09N105W AND FROM 07N111W TO 09N128W TO 08N140W. ...DISCUSSION... GULF OF PAPAGAYO...NE-E WINDS WILL PULSE AT 20-25 KT DURING THE MAXIMUM NOCTURNAL DRAINAGE TONIGHT THROUGH THU NIGHT...THEN MAX AT 15-20 KT ON FRI NIGHT. THE NE SWELL PROPAGATING SW FROM THE GULF OF PAPAGAYO...WILL MIX WITH NW SWELL FROM THE GULF OF TEHUANTEPEC EVENT...AS WELL AS LONG PERIOD CROSS-EQUATORIAL SWELL...RESULTING IN COMBINED SEAS OF 6-9 FT AS FAR S AS 09N92W. EXPECT THE NOCTURNAL MAX TO ONLY REACH 15-20 KT ON FRI NIGHT INTO SAT MORNING. A SURFACE RIDGE EXTENDS FROM 32N137W TO 18N106W WITH NE 15-20 KT TRADES BETWEEN THE RIDGE AND ITCZ ACROSS THE WATERS W OF 120W. LONG PERIOD NW SWELL IS MIXING WITH THE ASSOCIATED NE TRADE WIND SWELL...AND ALSO WITH LONG PERIOD CROSS-EQUATORIAL SOUTHERLY SWELL...RESULTING IN COMBINED SEAS OF 7-10 FT WITHIN THIS AREA OF ENHANCED TRADES. THE NW SWELLS ARE GRADUALLY SUBSIDING AND THE AFFECTED AREA OF SEAS 8 FT OR GREATER WILL SHRINK TO THE WATERS FROM 08-15N BETWEEN 117-140W TONIGHT. THE GRADIENT WILL TIGHTEN A LITTLE ON WED WITH NE-E 15-20 KT TRADES ENHANCED ACROSS THE DISCUSSION WATERS FROM 08-25N W OF 126W WITH SEAS 6-9 FT ON WED NIGHT. A COLD FRONT WILL APPROACH THE NORTHERN PORTION OF THE BAJA CALIFORNIA PENINSULA ON THU NIGHT. STRENGTHENING HIGH PRESSURE IN THE WAKE OF THE FRONT WILL SUPPORT NORTHERLY 20-25 KT WINDS ACROSS THE ENTIRE DISCUSSION AREA W OF A LINE FROM 32N117W TO 08N140W LATE THU NIGHT. ALTHOUGH THE GRADIENT WILL BEGIN TO RELAX ON FRI...THE ASSOCIATED NW SWELL...RESULTING IN SEAS 8 FT OR GREATER...WILL ARRIVE ALONG THE PACIFIC COAST OF THE BAJA PENINSULA TO THE N OF 29N ON FRI MORNING...WITH THESE CONDITIONS SPREADING AS FAR S AS 25N LATE FRI NIGHT...THEN QUICKLY SUBSIDING ON SAT. GULF OF CALIFORNIA...NW WINDS ARE CURRENTLY AT 10-15 KT ACROSS ENTIRE THE GULF WATERS ARE EXPECTED TO QUICKLY DIMINISH TO 5-10 KT THIS MORNING. LIGHT AND VARIABLE WINDS ARE EXPECTED ON WED... THEN BECOMING SOUTHERLY WED NIGHT. THE SOUTHERLY WINDS WILL INCREASE OVER THE NORTHERN GULF WATERS EARLY THU AHEAD OF A COLD ARRIVING ON THU AFTERNOON. THE FRONT SHOULD REACH AS FAR S AS 27N LATE FRI ACCOMPANIED BY A SW-W-NW 10-15 KT WINDS SHIFT. $$ NELSON