000 AXPZ20 KNHC 141607 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Fri Oct 14 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 1530 UTC. ...TROPICAL WAVE... A tropical wave is along 102W S of 16N, and is located at the leading edge of an enhancement of deep tropical moisture. Only isolated moderate convection is within 90 nm of the wave axis. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends across Panama and exits Costa Rica at 09N84W to 10N100W to 15N114W to a 1009 mb low near 14N119W to 09N130W. The ITCZ axis extends from 09N130W to beyond 11N140W. Outside of the low center, scattered moderate convection is within 24 nm N of the monsoon trough between 89W and 99W. Clusters of moderate to strong are from 12N to 16N between 108W and 113W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Near gale winds over the Gulf of Tehuantepec will continue through this afternoon. High pressure over and north of the Gulf of Mexico is shifting eastward, which will reduce wind funneling and pressure forcing through the Tehuantepec Gap. However, the gap winds will continue to support fresh to locally strong Tehuantepec winds that will be enhanced by nocturnal drainage flow through each morning through early next week. Elsewhere, a high pressure ridge extends SE from a 1019 mb high near 28N129W to near the Revillagigedo Islands. This ridge is supporting moderate to locally fresh northwest to north winds off the Baja California coast, with seas primarily between 5 to 7 ft. The ridge will weaken today as a cold front crosses the far NW corner of the forecast region, but will continue to dominate the offshore waters of Baja through the upcoming weekend. Long period northwest swell, generated by strong winds well north of the cold front and a storm system northwest of the area, will push into the waters off Baja California Norte later today and then Baja California Sur tonight, with seas building to 8 to 10 ft Saturday morning. A high pressure ridge will build N of the area and intensify by Sunday night which will result in winds increasing to 25 kt with seas to 11 ft possible off the northern portion of Baja California Norte, that includes forecast zone PMZ009. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate southwest winds prevail south of the monsoon trough...including the waters between Ecuador and the Galapagos Islands. Mainly light to gentle winds are north of the monsoon trough. Seas are 4 to 6 ft south of the monsoon trough are mainly associated with long period southwest swell. Winds south of the monsoon trough may increase to moderate to locally fresh by Monday. Isolated to scattered moderate convection will persist within 120 nm mainly north of the monsoon trough axis through tonight. REMAINDER OF THE AREA... A broad area of low pressure is located near 14N119W with an estimated central pressure of 1009 mb. Fresh to locally strong winds are within about 120 nm in the N quadrant of the low center with seas to 8 ft. Clusters of moderate to isolated strong convection are from 13N to 17N between 114W and 120W. Some slow development of this disturbance is possible during the next several days while it moves west- northwestward at around 15 mph. A previously analyzed low pressure center has opened into a trough which now extends from 22N135W to 15N135W. Fresh to strong winds extend from around 19N to 23N within about 90 nm of either side of the trough axis, as confirmed by a 0640 UTC scatterometer pass. These winds are mainly the result of the pressure gradient between the trough and a ridge to the N. These fresh to strong winds will decrease through today as ridging north of the trough erodes due to the approach of a cold front. Long period NW swell with seas up to 12 ft spreading across the NW waters. This swell has been generated by a storm system well to the north. A cold front associated with this storm system will weaken considerably as it reaches the NW corner of our area today, with stronger winds remaining north of 30N. A pre-frontal trough extends from 30N133W to 27N139W with moderate NW winds north of the trough. The long period swell event will bring seas of 8 to 12 ft across the waters NW of a line from 29N115W TO 22N114W TO 10N125W TO 06N140W by Saturday morning. The 8 to 12 ft swell is expected dominate most of the forecast waters N of 10N W of 110N by Saturday night, with swell lingering into Monday morning. Another batch of swell of 8 to 10 ft may cross SE from 30N late Monday. Expect the highest seas for both of these swell events over the NW waters. $$ ASL/HC