000 AXPZ20 KNHC 310302 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 000 UTC Wed Aug 31 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...SPECIAL FEATURE... Hurricane Lester is centered at 17.8N 136.5W or about 1225 statue miles east of Hilo, Hawaii at 0300 UTC Aug 31, moving west or 260 degrees at 11 kt. Estimated minimum central pressure is 948 mb. Maximum sustained winds are 120 kt with gusts to 145 kt. Scattered strong convection is within 90 nm over east semicircle. Scattered moderate to isolated strong elsewhere within 120 nm over west semicircle. Lester is forecast to cross 140W on Wed. Refer to the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP3/WTPZ23 KNHC, and the latest high seas forecast under WMO header FZPN02 KWBC for additional details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 13N99W to 11N108W to 12N116W to 15N127W. Scattered moderate to isolated strong convection within 60 nm along the coast of Costa Rica, within 75 nm along the coast of Guatemala and Mexico between 91W and 94W, and within 75 nm along the coast of west Mexico from 19N to 22N. Scattered moderate convection is from 05N to 10N between 83W and 89W, from 12N to 16N between 105W and 109W, and within 90 nm south of the monsoon trough between 109W and 113W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A sub-tropical ridge is maintaining moderate NW flow with 3 to 5 ft seas across the Pacific waters along the Baja Peninsula, except moderate to fresh northwest flow, with seas 6 to 9 ft, is forecast across the waters north of 30N through Wed night. Light and variable winds are expected elsewhere along the Pacific coast of Mexico, with combined seas of 3 to 6 ft primarily due to long- period cross-equatorial swell. A thermal trough will meander over the Baja Peninsula, and across the northern Gulf of California supporting light southerly flow across the Gulf of California into the upcoming weekend when moderate southwest flow is forecast between 30N and 31N. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to locally fresh southwesterly winds will prevail south of the monsoon trough axis with light to gentle west to northwest winds forecast north of the trough axis. Long period cross equatorial southwesterly swell will with combined seas of 5 to 8 ft will subside on Thu. REMAINDER OF THE AREA... Except as previously mentioned, a 1030 mb surface high is near 40N153W, drifting southeast, with a ridge extending southeast to near 25N124W. An area of low pressure could form a few hundred miles southwest of the south-central coast of Mexico by the weekend. Environmental conditions are expected to be conducive for slow development in 3 to 5 days as this system tracks northwestward. Otherwise, the ridge will extend from 32N138W to 20N122W on Thu evening as conditions associated with Lester shift west of 140W. By then, moderate to fresh northeast to east flow is expected south of the ridge and north of the monsoon trough with combined seas of 4 to 7 ft, with little change through the weekend. Moderate to fresh north to northeast flow is forecast north of the ridge, with 5 to 7 ft combined seas through the weekend. $$ PAW