000 AXPZ20 KNHC 180921 CCA TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0855 UTC Tue Aug 18 2020 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 0830 UTC. ...SPECIAL FEATURES... Hurricane Genevieve is centered near 17.4N 107.1W at 18/0900 UTC moving NW at 15 kt. The estimated minimum central pressure is 966 mb. Maximum sustained wind speed is 95 kt with gusts to 115 kt. Numerous moderate to strong convection is noted within 75 nm of center except 120 nm NE quadrant. Scattered moderate convection is occurring elsewhere from 15N to 19N between 102W and 109W. Numerous strong convection is noted well north of Genevieve, from 20N to 24N between 106W and 109W. The center of Genevieve is expected to move parallel to but well offshore the coast of southwestern Mexico during the next day or so. Genevieve is forecast to move to the southwest of the southern portion of the Baja California peninsula on Wed night and Thu. Additional rapid strengthening is forecast during the next 12 to 24 hours. Large swells produced by Genevieve will spread northward along the southwestern and west-central coast of Mexico to the Baja California peninsula through Wed. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPEP2.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMEP2.shtml for more details. ...TROPICAL WAVES... A tropical wave axis is analyzed along 90W south of 19N, moving W at 10 kt. Scattered moderate isolated strong convection is noted from 11N to 15N within 180 nm of the wave axis. A tropical wave axis is analyzed along 117W south of 20N, moving W at 15 kt. Scattered moderate convection is noted from 08N to 12N between 114W and 118W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N76W to 11N86W to 15N97W, then resumes west of Hurricane Genevieve from 13N112W to 16N121W to 14N127W to 1010 mb low pressure near 15N138W to 13N140W. Besides the previously described convection, scattered moderate isolated strong convection is noted within 120 nm N of the monsoon trough between 92W and 96W. Scattered moderate convection is occurring from 10N to 15N W of 137W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details about Hurricane Genevieve, which is expected to continue rapidly strengthening during the next day or so while moving parallel to but well offshore of the coast of southwestern Mexico. Genevieve will produce extremely dangerous, life-threatening marine conditions over the next several days as it crosses the offshore waters. Elsewhere, mainly gentle northerly winds prevail over the Baja California offshore waters. Recent altimeter data shows 3-5 ft seas offshore of Baja California Sur. A line of strong convection is noted in GOES-16 satellite imagery and lightning data moving westward off the coast of Nayarit and Jalisco. Gusty winds and locally rough seas can be expected near these storms. Farther south, a large area of fresh to strong southerly flow is noted in recent scatterometer data well to the S and SE of Genevieve, which is supporting large seas across the offshore waters of southern Mexico. In fact, an earlier altimeter pass showed 6-8 ft seas extended as far as the Tehuantepec region. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Overnight scatterometer data shows gentle to moderate southerly flow to the south of the monsoon trough E of 90W, with light and variable winds north of the trough off the coasts of Guatemala, El Salvador, and Nicaragua. Seas are generally 4-6 ft across the region. The monsoonal flow will freshen during the middle and latter parts of the week as the monsoon trough lifts northward. This will build seas to 7-10 ft off Central America by Thu night. REMAINDER OF THE AREA... Please see the Special Features section above for information about rapidly strengthening Hurricane Genevieve. A broad area of fresh to strong southerly winds persists well south of the center of Genevieve, with associated seas of 8-11 ft based on overnight altimeter data. The 1010 mb remnant low of former Tropical Depression Fausto is centered near 23.5N128W. No convection is associated with this low pressure, but a recent altimeter pass indicates peak seas are 7-8 ft in NE swell within the northern semicircle. This low is expected to continue weakening and dissipate by Wed morning. Elsewhere, a partial scatterometer pass near the remnant low of Ten-E around 15N138W shows fresh winds in its NW quadrant, with seas likely to 8 ft. This low will continue moving westward and likely cross 140W tonight or early Wed. Moderate southerly monsoon flow will freshen during the middle and latter parts of the week, resulting in areas of 8+ ft seas south of the monsoon trough generally E of 105W. $$ B Reinhart