000 AXPZ20 KNHC 161603 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun Oct 16 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 1200 UTC surface analysis and satellite imagery through 1515 UTC. ...SPECIAL FEATURE... Low pressure centered near 16N125W is embedded within the monsoon trough. Scattered moderate convection is from 10N to 18N between 122W and 129W. There is currently a medium probability that this low will develop into a tropical cyclone within the next 48 hours as it moves westward. Please refer to the latest eastern North Pacific Tropical Weather Outlook under AWIPS/WMO headers TWOEP/ABPZ20 KNHC for more information. ...TROPICAL WAVE... The axis of a tropical wave is near 109W between a 1009 mb low near 10N109W and 16N. Isolated moderate convection is S of 12N along the wave axis. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from Central America near 14N90W to to a 1009 mb low pressure area near 10N109W to another 1009 mb low near 16N125W to 11N140W. Other than convection associated with the special feature low near 16N125W, scattered moderate and isolated strong convection is from 07N to 12N between 92W and 114W, from 09N to 14N between 128W and 140W, and from 05N to 11N E of 87W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A dissipating 1019 mb high is centered near 26N131W with one ridge axis that extends east to offshore Baja California Norte, and another ridge axis that extends southeast to near the Revillagigedo Islands. Moderate NW winds prevail over the coastal waters offshore Baja California. NW swell of 7 to 10 ft continue to affect areas to the west of Baja California and will continue to do so through Wednesday. A new area of high pressure will build SE from the NE Pacific late tonight through Monday which will increase NW winds W of Baja California Norte to 20-25 kt with seas building to 11 ft. The ridge will weaken slightly mid week which will lessen winds to under 20 kt. Over Gulf of Tehuantepec, winds currently in the 20-25 kt range will decrease to 10-15 kt this afternoon before pulsing to 20-25 kt once again tonight. The strong winds support seas to 8 ft this morning. The pressure gradient north of the area over the Gulf of Mexico will lessen on Monday through Wednesday which will keep winds mainly under 20 kt. Weak high pressure to the north will help increase Tehuantepec winds back to fresh to strong Thursday and Friday morning. Then, strong high pressure north of the area will increase N to NE Tehuantepec winds likely to Gale force late Friday and into the next weekend. Elsewhere, light to gentle winds prevail. Seas are 2 ft or less over the Gulf of California, and around 4-6 ft elsewhere. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate southwesterly winds prevail south of the monsoon trough. Mainly light to gentle winds continue north of the monsoon trough. Seas are in the 4-6 ft range in a mix of northwest and southwest swell. Winds will freshen south of the monsoon trough early this week into the middle of the week. Seas will gradually increase to near 7 ft through the early to middle part of the week with the assistance of the southerly wind surge south of the monsoon trough and cross equatorial SW swell. REMAINDER OF THE AREA... Weak high pressure centered near 26N131W extends a ridge axis southeast to near the Revillagigedo Islands. The pressure gradient between this area of high pressure and the area of low pressure mentioned in the special feature section is supporting fresh to strong winds over the northwestern semicircle of the low, with seas of 10-12 ft. Elsewhere, moderate to fresh winds prevail between the monsoon trough and the ridge. Light and variable winds prevail within the high pressure center with light to gentle winds along the ridge axis. A NW swell event continues with seas 8-12 ft or greater generally north of 10N and west of 114W. A cold front extends across the NW waters with moderate to fresh NW winds north of the front. The high centered over the northern waters will dissipate as the cold front sweeps east through tonight. The front will then dissipate through Monday while high pressure north of the front builds southeast. This new area of high pressure will support moderate to fresh northeasterlies over most of the area N of 10N W of 120W Monday night through Wednesday. A re- enforcement of NW swell over these waters will occur Monday through Monday night. This secondary swell event will begin to subside mid week. Elsewhere, the combination of SW winds south of the monsoon trough and NW swell will build an area of seas 8-10 ft mainly from 02N and 10N between 95W and 110W tonight through the middle of the week. SW swell of 8-9 ft is also forecast to propagate NE to near the equator between 90W and 115W Monday night through Thursday. $$ LATTO