000 AXPZ20 KNHC 030858 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 711 UTC Sat Feb 3 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 0815 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A strong high pressure ridge along the Sierra Madre Oriental mountains of Mexico is maintaining a strong pressure gradient over the Isthmus of Tehuantepec. The pressure gradient will be strong enough to generate gales of the Gulf of Tehuantepec this afternoon until 18Z. From this evening through Mon, the high pressure ridge over the western Gulf of Mexico will shift E and allow winds over the Gulf to decrease to strong tonight and then to light and variable Sun night. The next gap wind event is slated for Mon morning through Tue afternoon, but winds are only expected to peak at strong speeds. Please refer to the East Pacific High Seas Forecast under AWIPS/WMO headers HSFEP2/FZPN03 KNHC for more details. EASTERN PACIFIC ASHFALL ADVISORY: Fuego Volcano at 14.5N 90.9W over S Guatemala is erupting. Volcanic ash may be reaching the surface W of the volcano to near the coast of Guatemala N of 13.5N between 91W and 92W. Low level visibility 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 07N80W to 05N93W. The ITCZ continues from 05N93W to 05N98W TO 08N109W to 09N114W, then resumes from 08N119W to 08W130W to beyond 07N140W. Scattered moderate and isolated strong convection is present from 10N to 14N between 118W and 125W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec: Please refer to special features section for more information on the next gale force gap wind event. Elsewhere over the open waters, seas are expected to remain at 4 to 6 ft through Mon as a fairly tranquil pattern prevails. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fuego Volcano in Guatemala: Please refer to special features section for more information on this ongoing volcanic eruption. Nocturnal winds will pulse to between fresh and strong speeds each night over the Gulf of Papagayo through Fri night. Areal coverage of gap winds near the Gulf of Papagayo will increase Thu and Fri. This will allow the area of 8 ft seas downwind from the Gulf of papagayo to combine with the area of 8 ft seas downwind from the Gulf of Tehuantepec. Elsewhere N of 09N, gentle to moderate offshore flow will prevail. Moderate to fresh winds will pulse to strong during overnight hours in the Gulf of Panama as well through Wed night. Elsewhere, light to gentle S to SW winds will generally prevail S of 09N through the middle of next week. REMAINDER OF THE AREA... A mix of NE and NW swell is generating an area of 8 ft seas located from 09N to 12N between 125W and 132W. This area will slowly propagate W through Sun afternoon. Another pulse of NE swell generated by the current Gulf of Tehuantepec gap wind event will cause seas to build to 8 ft as it propagates across the waters S of 14N and E of 100W, then seas will fall below 8 ft by Sun afternoon as the swell decay. Elsewhere, a ridge of high pressure extending SW across the NW part of the discussion area will persist the next several days. NW swell generated by a fetch of winds to the W of a nearly stationary frontal boundary currently well to the NW of the discussion area will propagate E and generate a new area of 8 ft seas stretching from 10N to 30N between 130W and 140W on Sun and Mon. $$ CAM