000 AXPZ20 KNHC 182119 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1927 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 1800 UTC surface analysis and satellite imagery through 2030 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 13N102W to a 1010 mb low pres near 11N113W to 10N119W to 14N130W to 1008 mb low pres near 13N134W to 10N140W. Numerous moderate and isolated strong convection is seen from 11N to 17N between 128W and 132W. Scattered moderate and isolated strong convection is present from 08N to 13N between 99W and 119W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A high pres ridge extends SE from 32N130W to SE of the Revillagigedo Islands at 17N108W. 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 lessen over this area through the 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. Fresh N winds will pulse over the Gulf of Tehuantepec each night through Wednesday night. A strong area of high pres behind a cold front over the Gulf of Mexico will support 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. 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. 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 6 hours. Scattered moderate and isolated strong convection is evident over these zones N of 06N. REMAINDER OF THE AREA... 1008 mb low pres is centered near 13N134W. 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 390 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 15N126W to 11N140W. 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. 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