000 AXPZ20 KNHC 312113 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Tue Oct 31 2017 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 09N84W to 1009 mb low pressure near 11N105W to 12N120W to 1011 mb low pressure near 11N123W to 09N134W. The ITCZ continues from 09N134W to beyond 09N140W. A cluster of moderate to isolated strong convection is noted from 11N to 14N between 116W and 119W. Scattered moderate convection is from 09N to 11N between 110W and 114W, and within 30 nm N of ITCZ W of 138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The significant swell event affecting the coast of Baja California the past few days continues to decay. Currently, an altimeter pass indicates seas of 5 to 7 ft. Seas will subside to the range of 4-5 ft tonight. The pressure gradient associated with a weak ridge extending into the offshore waters of Baja California will produce light to gentle NW winds through Friday. The next gap wind event through isthmus of Tehuantepec region is forecast beginning on Friday night, with strong northerly winds expected to surge out across the Gulf of Tehuantepec as high pressure slides eastward across the northern Gulf of Mexico. Presently, the model guidance indicates that these winds may reach to near gale force Friday through Sunaday, and minimal gale force Saturday night into Sunday. Wave model guidance shows seas building up to around 13 or 14 ft on Sunday. The forecast calls for gale conditions possible during the upcoming weekend. Gulf of California: Gentle to moderate winds are expected across the gulf through Saturday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Latest scatterometer data indicates gentle to moderate winds S of the monsoon trough, and light winds elsewhere. Seas generally are between 4-6 ft. Little change in winds and seas is expected through Friday. REMAINDER OF THE AREA... The NW swell event from the past few days continues to propagate through the forecast waters west of about 97W, supporting seas of 7-9 ft. As the swell energy decays into Thursday, expect for these seas to subside to 6-8 ft at that time. A weak cold front is forecast to reach the NW corner of the forecast area on Wednesday night, then move slowly southeastward through Friday with little impact in winds and seas. Global model guidance suggests that broad strong high pressure will build southeastward over the NW waters Friday night and Saturday, pushing the front eastward. At that time, guidance is consistently depicting fresh to strong northerly winds behind the front and building seas of 12-14 ft in long period NW swell. In the tropics, a series of weak low pressure systems will linger along the monsoon trough region as mentioned above. Although tropical cyclone formation is not expected through the end of the week with any of the lows, the western most one analyzed near 11N123W is forecast to move in a generally northwesterly direction through Friday before weakening to a trough late Friday and Saturday. $$ GR