000 AXPZ20 KNHC 050332 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sun Feb 5 2017 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. The pressure gradient between a high pressure ridge across the eastern slopes of the Sierra Madre Oriental mountains and the equatorial trough over the eastern north Pacific is supporting minimal gale force winds over the Gulf of Tehuantepec, especially during the overnight and early morning hours. The ridge will weaken over the next 24 hours, which will loosen the pressure gradient and diminish winds below gale force by Sunday afternoon. Then, winds will briefly increase again to minimal gale force Sunday night. Veering winds over the southwest Gulf of Mexico early next week will further diminish winds funneling into the Gulf of Tehuantepec, and winds are expected to diminish to 20 kt or less late Monday. However, another pulse of 20-25 kt northerly winds is forecast to occur by Monday night. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 03N90W to 02N105W. The ITCZ extends from 02N105W to 04N130W to beyond 06N140W. A cluster of moderate convection is noted within 120 nm north of the ITCZ between 117W and 119W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see above for more on the latest Gulf of Tehuantepec gale force gap wind event. Elsewhere, high pressure of 1020 mb centered near 30N124W extends a ridge southeast to near the Revillagigedo Islands. The pressure gradient between the ridge and a surface trough over western Mexico is supporting gentle to moderate northerly winds and seas of 7-8 ft in NW swell W of the western coast of the Baja California peninsula. Light to gentle winds and seas generally under 2 ft prevail over the Gulf of California. During the next 24 hours, the high pressure center will move SE to a position near 26N121W as a cold front clips the far north waters. Seas are forecast to subside to 6-7 ft by Sunday afternoon. Looking ahead, marine guidance indicates increasing winds to 15-20 kt Tuesday and Wednesday across the offshore waters, mainly N of 25N, and over the central Gulf of California. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The strong trade winds in the southwest Caribbean Sea will continue to funnel through the Central America gap regions to extend into the Gulfs of Papagayo and Panama. The gap wind event in the Gulf of Papagayo is forecast to persist through Thursday, with winds reaching 25-30 kt tonight and early Sunday morning, and seas building in and downstream of the Gulf to 9 ft. Northerly winds in the 20-25 kt range will continue to blow into the Gulf of Panama through Sunday night, then northerly winds of 15-20 kt are expected thereafter. Otherwise, light and variable winds and 4-6 ft seas will prevail elsewhere. REMAINDER OF THE AREA... Relatively weak high pressure prevails over the northern waters. The pressure gradient between this area of high pressure and lower pressure in the vicinity of the ITCZ is supporting mainly fresh to locally strong trades north of the ITCZ to near 15N. Seas of 8-10 ft are within the area of the trades based on a recent altimeter pass. These marine conditions are forecast to continue over the next few days. A cold front will push into the far northwest waters late tonight. This cold front will not make it very far into the area before dissipating. The main impact of this front will be a new set of NW swell propagating into the forecast region, with seas peaking near 11 ft on Sunday. A stronger cold front is forecast to approach from the west Monday and Tuesday. This front will be associated to a deep low pressure center. The strong pressure gradient related to this system will reach the NW corner of the forecast area Monday night into Tuesday, with increasing winds and building seas. Currently, marine guidance indicates S-SW of 20-30 kt and seas up to 15-16 ft near 30N140W. $$ GR