000 AXPZ20 KNHC 110325 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Nov 10 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 0300 UTC. ...SPECIAL FEATURES... A gale warning remains in effect for the Gulf of Tehuantepec. Strong to minimal gale force northerly winds are expected across the Tehuantepec area through early Friday morning. Then, fresh to strong northerly winds, in the 25-30 kt range, will continue to surge into the Gulf of Tehuantepec through Monday. The pressure gradient between high pressure over eastern Mexico and lower pressure within the monsoon trough over the eastern North Pacific is supporting this gap wind event. Gusty winds, reaching minimal gale force are expected to likely occur during the overnight and early morning hours with the assistance of the nocturnal drainage flow. Seas are forecast to build to 11 ft in and downstream of the Gulf, with seas of 8 ft or greater reaching near 100W tonight. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 1010 mb low pressure near 08N92W to 10N102W to 1009 mb low pressure near 13.5N111W to 10N115W to 1011 mb low pressure near 13N122W to 09N130W. the ITCZ axis continues from 09N130W to 09N140W. Scattered moderate isolated strong convection is noted from 09N to 17N between 102W and 110W. Scattered moderate convection is from 09N to 11N between 110W and 121W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A gale warning is in effect for the Gulf of Tehuantepec. Please, see Special Features section for details. Marine guidance suggests another gale force gap wind event across the Gulf of Tehuantepec on Tuesday. For the Gulf of California...high pressure building across the U.S. Great Basin and Rocky Mountains will support moderate to fresh northwest winds over the northern Gulf this evening through early Friday morning. Expect seas building to 4-5 ft winds these wind speeds. A set of long period northwest swell is propagating through the offshore waters off the west coast of the Baja California peninsula, with seas in the 8-12 ft range per a recent Altimeter pass. A second set of northwest swell will reach the waters off Baja California Norte early this weekend, reinforcing the previous swell event. This will maintain seas in the 8 to 10 ft range over the open Mexican offshore waters through early next week. Elsewhere seas will remain below 8 ft. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Winds will pulse the next several days over the Gulf of Papagayo...peaking near 15 to 20 kt during the late night and early morning hours, with seas building to 5-6 ft downstream of the Gulf of Papagayo. Elsewhere, light to gentle winds will prevail over the waters north of 10N, with gentle to moderate mainly southwest winds south of 10N. Seas of 4 to 6 ft will prevail across the region through the end of the week in mixed northwest and southwest swell. REMAINDER OF THE AREA... High pressure of 1018 mb is centered near 29N129W. The pressure gradient between this area of high pressure and lower pressure within the monsoon trough is supporting moderate to locally fresh trade winds north of the monsoon trough to 18N as depicted in the latest ASCAT passes. Three low pressure systems are noted within the monsoon trough as previously mentioned. The low pressure located near 13.5N111W is producing a large but disorganized area of cloudiness and thunderstorms. Strong upper-level winds currently affecting this system are expected to increase further during the next few days, and significant development of the low is not likely while it moves generally northward at 5 to 10 kt. The main story over these waters is the long period northwest swell which is propagating across the area, with wave heights as high as 14 ft based on altimeter passes. Seas greater than 8 ft associated to this event are found over much of the waters west of 110W. This swell event will continue to spread southeast over the next couple of days while slowly subsiding. A second set of large, long period northwesterly swell will propagate into the northwest waters tonight behind a cold front. Seas associated to this swell event will peak near 16 ft over the far northwest waters late Friday. The cold front is forecast to extend from 30N137W to 26N140W early Friday morning, reaching from 30N132W to 24N140W Friday evening. $$ GR