000 AXPZ20 KNHC 200244 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 042 UTC Thu Oct 20 2016 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... A gale warning remains in effect for the Gulf of Tehuantepec. This gap wind event will be associated with a cold front moving S through the western Gulf of Mexico Thursday night through Friday night. N winds of 25-30 kt will begin to surge into the Tehuantepec area tonight. Winds are forecast to continue increasing to minimal gale force by Friday morning with seas building to 9-13 ft by Friday afternoon. Model guidance has trended downward with respect to the peak intensity of this event. However, model guidance suggests this event will be long lived with winds to gale force possible until the end of next week. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 12N92W to 11N100W to 1007 mb low pres near 13N114W to 10N122W to 14N134W to 13N140W. Numerous moderate and isolated strong convection is present from 10N to 13N between 94W and 96W. Scattered moderate convection is found within 180 nm either side of the the monsoon trough axis E of 110W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge extends SE from 32N133W to SE of the Revillagigedo Islands at 16N108W. The pres gradient between the ridge and low pres over northern Mexico is generating fresh to strong N winds across the waters N of 26N between 118W and 126W. Seas in this area between 8 and 10 ft. Moderate NW winds prevail W of Baja California. The combination of these winds and long period NW swell support seas of 8 to 10 ft W of Baja California Norte, and 6 to 8 ft seas W of Baja California Sur. The high pres center will shift SW and dissipate in about 24 hours. The ridge will weaken through Friday as a cold front approaches the region. The front is expected to stall and weaken near 30N140W by late Friday. Residual long period swell still arriving will subside during the next few days. A new batch of swell of 8 to 9 ft generated N of the front is forecast to arrive offshore Baja California Norte Saturday through Sunday. Winds will increase across the northern part of the Gulf of California tonight as high pres builds across the Great Basin. By Thursday morning...expect NW winds of 20-25 kt and seas of 5-6 ft N of 30N, and NW winds of 15-20 kt with seas of 4-5 ft across the central waters, mainly N of 26N. Winds will subside to fresh speeds by Thursday night. Moderate to fresh winds will continue across the Gulf of California until early Friday morning. Farther S...a gap wind event, reaching gale force, is expected to begin across the Gulf of Tehuantepec tonight. See Special Features section for details. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh S to SW winds are noted in satellite-derived wind data S of 10S. Satellite-derived sea height data show seas of 5 to 7 ft in the same area. Mainly light to gentle winds and seas of 4 to 6 ft continue N of 10N. A mix of NW and SW swell predominate W of 100W, while SW swell predominate E of 100W. These conditions are forecast to prevail over the next few days. REMAINDER OF THE AREA... A low pres system is observed within the monsoon trough near 13N114W. An area of fresh to locally strong SW winds on the SE side of the low is expected to accompany this system during the next day or so as it drifts NW to N. Some development of this system is possible during the next several days as it drifts N or NW. The pres gradient between the ridge to the N and the trough is generating an area of fresh to strong winds from 14N to 17N W of 135W. Winds and seas will continue to diminish across the west- central waters during the next couple of days. Currently, seas of 8-11 ft, primarily in NW swell, dominate the forecast region W of a line from 22N135W to 13N123W to 10N140W and N of 25N between 117W and 129W. Seas will gradually subside over the next couple of days, but another set of long period NW swell will head SE from 32N140W by late Friday. Elsewhere, the combination of SW winds S of the monsoon trough and NW swell will generally support seas of 8-10 ft from 07N to 15N between 95W and 120W. Cross-equatorial SW swell continue to subside. Seas S of 02S between 98W and 104W in this area will subside below 8 ft by Thursday morning. $$ cam