425 AXPZ20 KNHC 161558 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1558 UTC Thu Aug 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURE... Tropical Storm Lane centered near 10.6N 127.6W at 16/1500 UTC or 1680 nm ESE of Hilo Hawaii moving W at 12 kt. Estimated minimum central pressure is 1001 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Numerous moderate and isolated strong convection is within 180 nm of the center of Lane. Scattered moderate convection is found to the NE from 10N to 13N between 118W and 123W, and to the SW from 06N to 08.5N between 128W and 133W. Lane is forecast to become a hurricane Fri morning, and is forecast to move W of 140W into the central Pacific by Sun morning. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCPEP4/WTPZ34 KNHC for more details. Volcanic ash associated with the Fuego Volcano in Guatemala near 14.3N90.5W is no longer being emitted. ...TROPICAL WAVES... A tropical wave extends from the Yucatan Peninsula southward into the E Pacific along 89W, N of 10N. Scattered moderate convection is from 10N to 13N between 86W and 94W, and also from 04N to 08N between 88W and 91W. A tropical wave along 110W extends from 07N to 17N. Scattered moderate convection is from 07N to 11N between 110W and 115W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 08N78W to 08N90W to 10N100W to low pressure near 09N107W to 10N117W. No ITCZ is noted E of 140W. Scattered moderate convection is from 03N to 07.5N E of 80W, N of 07N between 82W and 85W, from 13N to 06N between 94W and 97W, and also from 10N to 12N between 101W and 103W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Weak surface ridging extends from W of the offshore waters area to the SE across the Islas Revillagigedo. A weak trough associated with the remnants of tropical cyclone John lingered across the coastal waters near Punta Eugenio, and is aiding in producing gentle N to NW winds across the near shore waters of Baja California, with moderate NW winds further offshore. NW winds should remain moderate or weaker through Fri night until the ridge strengthens slightly and freshens the winds Sat through Sun. No significant gap wind events are expected in the Gulf of Tehuantepec, although nocturnal northerly drainage flow to around 20 kt is expected there each night. These fresh winds combined with long period southerly swell will support seas to 8 ft. Long-period S to SW swell originating S of the equator is impacting the Mexico offshore zones from Cabo Corrientes southeastward, producing seas of 4 to 6 ft. This swell is generating dangerous surf conditions along the coastlines and outer reefs. These swell will gradually be diminishing during the next two to three days. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough should remain near 10N during the next few days. Easterly winds N of the trough will be moderate or weaker, while southwesterly winds S of the trough will also be moderate breeze or weaker. The exception will be offshore of the Gulf of Papagayo where winds will pulse to moderate to fresh each night. Long-period SW swell originating S of the equator is also impacting the Central America, Colombia, and Ecuador offshore zones, producing seas of 5 to 8 ft. Large breaking waves are also occurring across these coastlines and outer reefs with localized breaking waves of 8 to 13 ft expected through late this morning. These swell will gradually be diminishing during the next two to three days. REMAINDER OF THE AREA... Please see the Special Features section for information on Tropical Storm Lane. A surface trough is found in the W central waters from 20N139W to 10N139W. Associated convection has diminished, however an area of fresh to strong winds and seas of 8 to 9 ft are found within an area bounded by 20N135W to 19N136W to 19N140W to 22N140W to 22N138W to 20N135W. This trough will shift W of 140W tonight. A 1011 mb surface low near 09N107W is lingering behind a tropical wave discussed above, with no associated deep convection. An area of 8 ft seas is found within an area bounded by 12N101W to 09N102W to 08N104W to 09N110W to 13N110W to 14N101W to 12N101W, although these seas will subside through tonight. $$ Lewitsky