000 AXPZ20 KNHC 162138 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1902 UTC Fri Feb 16 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 1800 UTC surface analysis and satellite imagery through 2030 UTC. ...SPECIAL FEATURES... Ashfall Advisory: The Fuego Volcano over S Guatemala near 14.5N 90.9W has resumed erupting. A plume of volcanic ash may reach to the surface through midday Sat N of 14N and E of 93W. Low level visibilities may be reduced to 1 nm. Mariners should exercise caution. If mariners encounter volcanic ash, they are encouraged to report the observation to the National Weather Service by calling 305-229-4425. Please refer to the East Pacific High Seas Forecast under AWIPS/WMO headers HSFEP2/FZPN03 KNHC for more details on the ashfall advisory. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 10N84W to low pres 1011 mb near 04N93W to low pres 1012 mb near 04N103W to 04N107W. The ITCZ continues from 04N107W to 05N118W to 05N130W to beyond 07N140W. No significant convection is currently associated with the ITCZ. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Large high pressure centered N of the area near 40N138W and weak troughing over NW Mexico is maintaining moderate to fresh NW winds across much of the area. A surface trough associated with deep layer troughing stretches from 23N120W to 19N122W to 14N123W. The trough will weaken during the next 24 to 48 hours as the associated mid to upper-level trough weakens and lifts out to the NE. Scattered showers associated with the surface trough will continue to advect NE across the waters adjacent to the Baja Peninsula. A cold front heading E across Baja California Norte will usher in strong winds and seas to 13 ft for the waters N of 30N Mon night. Winds and seas behind the front will quickly subside Tue and Wed. Gulf of Tehuantepec: A weak ridge extends SW from Florida over the Gulf of Mexico. The high will remain strong enough to support fresh to strong winds over the Gulf for the next few days, primarily during nocturnal hours when drainage flow is prevalent. Gulf of California: Moderate to occasionally fresh NW winds are expected over the Gulf as a tighter pressure gradient remains from strong high pressure to the NW. The gradient will then weaken this weekend as the high weakens, allowing conditions to improve. Looking ahead, a cold front will approach Baja California Norte Sun night. SW gap winds ahead of the front over the northern Gulf are expected to strengthen to between 20 and 30 kt kt ahead of the front Mon and Mon night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Strong NE to E winds will continue pulsing to 30 kt the next few nights. Downstream seas will build to 8-11 ft during the strongest winds each night. The area of high seas downstream from the Gulf of Papagayo is shrinking and has separated the area of seas associated with high winds over the Gulf of Tehuantepec. Gulf of Panama: Winds and seas have subsided below advisory levels as high pressure and strong winds over the SW Caribbean diminish. Moderate to fresh N to NE winds will generally prevail over the region through the middle of next week. Winds just S of the Azuero Peninsula could become locally strong during the morning hours Sun and Mon. Elsewhere, gentle to moderate offshore flow will prevail north of 09N, and light to gentle SSW winds will generally prevail south of 08N. REMAINDER OF THE AREA... A surface trough extends from 14N123W to 19N122W to 23N120W. A large area of cloudiness and showers associated with this system is displaced to the east of the surface trough axis. Scattered moderate and isolated strong convection is present from 13N to 19N between 115W and 120W. Coverage of cloudiness and showers is diminishing as the associated deep layer trough weakens and lifts out to the NE. A tight pressure gradient between the trough and strong high pressure centered well NNW of the area near 40N138W is supporting fresh to strong NE winds from 21N to 25N W of 138W, with seas of 9 ft. The pressure gradient between the high and lower pressure associated with the ITCZ is supporting fresh trades elsewhere, generally N of 15N and west of 120W. Seas in this area are 6 to 8 ft in mixed NE and NW swell. Trade winds will slowly diminish as the high centered NW of the discussion area weakens, and allow residual seas to steadily diminish into this weekend. Winds in this region will increase by the middle of next week as high pres to the N rebuilds. $$ CAM