000 AXPZ20 KNHC 260937 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Fri Aug 26 2016 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... Tropical Storm Lester is centered near 16.9N 114.5W at 26/0300 UTC or about 430 nm to the south-southwest of the southern tip of Baja California. Lester is moving W or 280 deg at 6 kt with maximum sustained winds of 50 kt with gusts to 60 kt. The estimated minimum central pressure is 1000 mb. Satellite imagery shows numerous strong convection within 105 nm NW and 45 nm SE semicircles of center. Scattered moderate isolated strong convection is noted elsewhere from 15N to 19N between 111W and 116W. A recent scatterometer pass indicate that the wind field associated with this tropical cyclone has slightly increased with winds of 20-30 kt extending within about 120 nm of the center, except within about 90 nm SW quadrant. Lester is forecast to continue moving away from the Mexican offshore waters on Friday, and is forecast to strengthen to a hurricane near 17N118W on Saturday. Please read the NHC forecast/advisory under AWIPS/WMO headers MIATCMEP3/WTPZ23 KNHC or the public bulletin under MIATCPEP3/ WTPZ33 KNHC for more details. Showers and thunderstorms continue to show signs of organization in association with a broad area of low pressure located near 13.5N133W or about 1340 miles east-southeast of the Big Island of Hawaii. Latest satellite imagery shows that overall cloudiness and convection has increased during the past hours in association with this area. Numerous moderate to scattered strong convection is noted mainly west of the center from 13N to 15N between 133W and 136W. Similar convection is from 12N to 13N between 134W and 136W. A tight gradient between this area of low pressure and the sub- tropical ridge to its north is resulting in moderate to fresh northeast winds from 13N to 18N and west of 130W based on a recent Ascat pass. Strong south-southwest were also indicated by the same Ascat pass to the south of the low from about 07N to 10N between 132W and 136W. Seas with these winds are within the 6 to 9 ft range. Environmental conditions are expected to be conducive for development, and a tropical depression is likely to form by this weekend while the low moves westward or west-northwestward at 15 to 20 mph. This system is forecast to move west of area by Saturday night. ...TROPICAL WAVES... No tropical waves at this time. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 12N95W to 09N101W to 11N109W. It resumes at 13N120W to low pressure near 13.5N133W 1008MB to beyond 11N140W. Scattered moderate isolated strong convection is from 07N to 10N between 95W and 102W, from 10N to 13N between 98W and 104W, and FROM 09N TO 11N W of 128W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Recent scatterometer data provided observations of moderate to locally fresh NW winds just off the Baja California coast due to the pressure gradient between the ridge over the north waters and a trough over Baja California. The same Ascat pass showed mainly moderate southerly winds across the Gulf of California or Sea of Cortez mainly N of 27N. This weather pattern is forecast to persist over the weekend. T.S. Lester is forecast to continue moving away from the Mexican offshore waters today. Please see above for details. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to moderate SW winds south of the monsoon trough will continue to spread to the coastal sections through Friday, then a light and variable onshore flow is expected Saturday and Sunday. ELSEWHERE... A broad surface ridge covers the remainder of the area, extending from a large 1040 mb high near 47N146W. The pressure gradient between the low pressure located near 13.5N133W and the ridge will yield fresh winds across the trade wind belt, generally from 21N southward to near the trough. Seas ranging from 6 to 8 feet presently in this area. $$ GR