000 AXPZ20 KNHC 280907 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 622 UTC Sun Jan 28 2018 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Storm Warning: A cold front over the NW Gulf of Mexico will move across the Gulf of Mexico through Mon. High pressure building in the wake of the front will help increase winds to gale force across Tehuantepec this morning. Winds will increase to strong gales tonight, then reach storm force Mon evening through Tue. The area of high pressure north of the area will then start to shift eastward, loosening the pressure gradient. Winds will diminish to gale force Wed, and fall below gale force Thu. Please refer to the East Pacific High Seas Forecast under AWIPS/WMO headers HSFEP2/FZPN03 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 07N78W to 05N90W. The ITCZ continues from 05N90W to 06N110W to beyond 09N140W. Scattered moderate isolated strong convection is noted within 60 nm of the ITCZ between 106W and 118W. Scattered moderate convection is noted within 30 nm north of the ITCZ between 130W and 134W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec: Please refer to the special features section above for more on the upcoming storm force gap wind event. Gulf of California: Winds of 20-25 kt prevail over the Gulf of California. The fresh to strong winds will prevail through Mon morning, with the potential for small areas of winds reaching 30 kt, mainly N of 29N, today. Peak seas are expected to build to 9 ft today. NW swell will continue subside over the waters off the coast of Baja California Norte. Seas west of the Baja Peninsula will subside below 8 ft by this evening. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh gap winds will pulse to strong the next several nights over the Gulf of Papagayo. Elsewhere N of 09N, gentle to moderate offshore flow will prevail through Mon then strengthen Tue through Wed. Gentle to moderate S to SW winds will prevail S of 09N the next few days. REMAINDER OF THE AREA... High pressure of 1030 mb is centered north of the area near 35N127W. The pressure gradient between this area of high pressure and lower pressure in the vicinity of the ITCZ is supporting fresh to strong trades from 08N to 20N and W of 120W, where seas are reaching 13 ft. NW swell also continues to propagate across these waters and is mixing with the wind generated NE waves. Seas 8 ft or greater associated with this swell cover much of the forecast waters west of 115W. The area of high pressure will shift further from the area and weaken the next couple of days. This will decrease areal coverage of the fresh to strong trades Sunday, with winds diminishing to 20 kt or less by Mon night. $$ AL