000 AXPZ20 KNHC 181628 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun Jul 18 2021 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 1600 UTC. ...SPECIAL FEATURES... Hurricane Felicia is centered near 15.7N 128.1W at 18/1500 UTC moving WNW at 10 kt. Estimated minimum central pressure is 954 mb. Maximum sustained wind speed is 115 kt with gusts to 140 kt. Numerous strong convection is present within 60 NM of the center. Peak seas are near 28 ft. A westward motion is expected to begin later today or tonight, followed by a west-southwestward track through Wednesday. Some additional weakening is forecast today, followed by faster weakening through midweek. Seas will gradual diminish but still around 23 ft peak by Tue.Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPEP1.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMEP1.shtml for more details. Tropical Storm Guillermo is centered near 17.9N 112.5W at 18/1500 UTC moving WNW at 10 kt. Estimated minimum central pressure is 1000 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Numerous strong convection is present within 120 NM of the center. Peak seas are near 15 ft. The tropical storm is forecast to turn westward with a slight increase in forward speed by tonight. A continued westward motion is then expected for the next few days. Some strengthening is possible today and early tomorrow. Gradual weakening is anticipated beginning Monday night. Seas for Guillermo should increase to around 20 ft Mon and Tue. 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 is near 87W, from 02N northward into Nicaragua, moving W at around 10 kt. Scattered moderate is noted north of 07N between 85W-90W. A tropical wave is near 95W from 05N northward to across southeast Mexico and continuing northward over the Gulf of Mexico, moving W at around 10 to 15 kt. No significant deep convection is noted in association with this tropical wave. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH AXIS EXTENDS FROM 07N78W TO 09N87W. ITCZ AXIS EXTENDS FROM 09N78W TO 07N110W. MONSOON TROUGH EXTENDS FROM 13N111W TO 12N125W. ITCZ AXIS EXTENDS FROM 11N130W TO BEYOND 09N140W. SCATTERED MODERATE ISOLATED STRONG FROM 05N-08N E OF 87W AS WELL AS FROM 11N-15N BETWEEN 110W-132W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see Special Features section for information on Tropical Storm Guillermo. Otherwise, fresh to strong northerly gap winds flow across the Tehuantepec region. Seas in this region are 5 to 8 ft. Light to gentle breezes are noted elsewhere off southern Mexico, with 4 to 7 ft seas primarily in SW swell. Farther north, a weak ridge west of the offshore forecast waters of Baja California is maintaining gentle to moderate NW-N winds, with the highest winds funneling along the coast. Seas are 4 to 6 ft off Baja California in a mix of long period S and NW swell. Moderate southerly flow is noted in the Gulf of California, with seas of 3 ft or less. For the forecast, Tropical Storm Guillermo near 17.9N 112.5W 1000 mb at 8 AM PDT moving WNW at 10 kt. Maximum sustained winds 45 kt gusts 55 kt. Guillermo will move to 18.3N 114.2W this evening, 18.6N 116.8W Mon morning, 18.7N 119.6W Mon evening, 18.7N 122.5W Tue morning, 18.6N 125.5W Tue evening, and 18.4N 128.4W Wed morning. Guillermo should weaken to a tropical depression near 17.9N 133.4W early Thu. Fresh to strong gap winds will pulse mainly at night in the Tehuantepec region through the early part of the week. In the Gulf of California, intermittent moderate to fresh SE winds are possible through the remainder of the weekend, and then again toward the end of the week as wind is drawn toward low pressure in the southeastern U.S.A. Mainly gentle to moderate winds will prevail elsewhere. A moderate NW swell may build west of Baja California Norte toward the end of the week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Fresh to locally strong offshore winds are noted in the Papagayo region with light to gentle winds elsewhere north of the monsoon trough. Gentle to moderate southerly flow is south of the monsoon trough. Seas are mainly in the 4 to 7 ft range. For the forecast, generally fresh NE to E winds will prevail across the Papagayo region, pulsing to strong during the late night and early morning hours. Elsewhere, gentle to moderate southerly flow will prevail south of the monsoon trough while light to gentle breezes are expected north of it. A moderate southerly swell may approach the waters offshore of Ecuador toward the end of the week. REMAINDER OF THE AREA... See the Special Features section for details on Hurricane Felicia and Tropical Storm Guillermo. Elsewhere, a broad ridge dominates the waters north of the monsoon trough. Moderate to fresh NE winds with 5 to 8 ft seas in mixed swell are prominent north of the monsoon trough and west of 130W, with mainly gentle to moderate winds north of the monsoon trough and east of 130W. SE to S winds and southerly swell of 5 to 8 ft prevail south of the monsoon trough west of the Galapagos. For the forecast, little change in marine conditions is expected through the middle of the week, outside of Hurricane Felicia and Tropical Storm Guillermo described in the Special Features section above. $$ Landsea/Lewitsky