000 AXPZ20 KNHC 190241 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2359 UTC Tue Oct 18 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N98W to 12N108W to 1010 mb low pres near 11N113W to 10N116W to 14N133W to 1007 mb low pres near 13N136W to 11N138W. The ITCZ continues from 11N138W to beyond 09N140W. Numerous moderate and isolated strong convection is seen from 12N to 15N between 131W and 140W. Scattered moderate and isolated strong convection is present within 180 nm either side of the monsoon trough axis E of 120W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A high pres ridge extends SE from 32N129W to near the Revillagigedo Islands at 19N112W. Moderate to fresh NW to N 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 NE and the ridge will weaken through Friday as a cold front approaches the region. The front is expected to stall and weaken just NW of the discussion area. Winds will therefore gradually decrease over this area this week, becoming light to moderate by Thursday and Friday. The long period swell will subside during the next few days. A new batch of swell of 8 to 9 ft is forecast to arrive offshore Baja California Norte over the weekend. A long lived and robust Tehuantepec surge event appears to be in store for the Gulf of Tehuantepec. Fresh N winds will pulse over the Gulf of Tehuantepec tonight and Wednesday night. A strong area of high pres behind a cold front over the Gulf of Mexico will generate fresh to strong N to NE Tehuantepec gap winds Thursday night, then Gale force winds Friday through Monday. Model guidance suggests that winds could reach strong gale force Friday night through Sunday. Gale force winds are then expected Sunday night through Tuesday. Elsewhere, light to gentle winds prevail. Surface troughing over the Baja peninsula continues to promote a light wind regime over the Gulf of California with seas generally 2 ft or less. Seas of around 4-6 ft prevail elsewhere. Fresh to strong winds are expected to develop over the Gulf of California N of 26N Wednesday night through Thursday night as the pres gradient tightens between the high pres ridge W of Baja and low pres over Arizona. These winds will support seas to 6 ft N of 30N. The pres gradient will relax once again over the Gulf on Friday, ushering in a light wind regime through at least Monday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh SW winds are evident S of 10N. Mainly light to gentle winds continue N of 10N. Seas generally range between 5 and 7 ft. A mix of NW and SW swell predominate W of 90W, while SW swell predominate E of 90W. These conditions are forecast to prevail through Friday. Shower and thunderstorm coverage within 250 nm of the coast of Central America N of 08N has decreased during the past 12 hours. Scattered moderate and isolated strong convection remains evident over these zones N of 06N. REMAINDER OF THE AREA... 1007 mb low pres is centered near 13N136W. This system has a low potential to become a tropical cyclone during the next few days as it moves W to WSW. The pres gradient between the high pres ridge NW of the Revillagigedo Islands and this low is generating fresh to strong winds in the NW semicircle within 330 nm of the low, with attendant seas of 10-12 ft. Elsewhere, moderate to fresh winds will prevail between the monsoon trough and the ridge the next couple of days...except light and variable winds along the ridge axis. Large long period NW swell have been affecting the area the last few days. Combined seas greater than 8 ft cover the area N of a line from 23N114W to 14N128W to 12N140W. Combined seas greater than 8 ft will continue in this area until the middle of the week, then diminish below 8 ft over the majority of the area by late this week as NW swell disperse and low pres currently near 13N136W moves W of 140W. Elsewhere, the combination of SW winds S of the monsoon trough and NW swell will support seas of 8-10 ft mainly from 01N and 14N between 95W and 125W through Saturday. Cross-equatorial SW swell of 8-9 ft will propagate NE between 95W and 115W and cause seas S of 02N to build to between 8 and 9 ft Wednesday. This area of seas will expend N to near 05N Thursday, then seas in this area will subside below 8 ft on Friday. $$ cam