000 AXPZ20 KNHC 150405 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Jul 15 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 0000 UTC surface analysis and satellite imagery through 0330 UTC. ...SPECIAL FEATURES... Tropical Storm Felicia is centered near 15.1N 116.7W at 15/0300 UTC moving WNW at 13 kt. Estimated minimum central pressure is 994 mb. Maximum sustained wind speed is 60 kt with gusts to 75 kt. Scattered moderate to isolated strong convection is noted within 60 nm in the northeast semicircle of Felicia, and within 120 nm in the southwest semicircle of the storm. Seas to 12 ft extend as far 90 nm in the northeast quadrant of the storm. Felicia is expected to intensify tonight then continue to move generally westward, reaching 120W by early Sat and 130W by early Sun. 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 WAVES... A tropical wave extends along 91W/92W from 06N northward toward the border of Mexico and Guatemala. The wave is moving W at around 15 to 20 kt. Scattered moderate to isolated strong convection is noted from 07N to 09N between 93W and 97W. Environmental conditions are expected to be conducive for gradual development over the next several days, and a tropical depression is likely to form this weekend well offshore of the southwestern coast of Mexico while the system moves westward or west-northwestward. Based on latest Tropical Weather Outlook, this system has a low chance of tropical cyclone formation through 48 hours, and a high chance of tropical cyclone formation through 5 days. Please refer to the latest Tropical Weather Outlook at: www.hurricanes.gov for details. A tropical wave extends along 102W/103W from 05N northward to near the southwest coast of Mexico. The wave is moving W at around 10 to 15 kt. Scattered moderate and isolated strong convection is noted from 10N to 12N between 98W and 103W. A tropical wave extends along 139W/140W from 05N to 16N, moving W at around 5 to 10 kt. Scattered moderate convection is evident from 11N to 12N between 136W and 138W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N78W to 08N80W to 12N110W, then resumes west of Tropical Storm Felicia near 14N120W to 1011 mb low pressure near 13N126W to 10N138W. In addition to the convection related to the tropical waves and Tropical Storm Felicia, scattered moderate convection is noted from 08N to 11N between 85W and 90W, from 09N to 11N between 106W and 112W. Scattered moderate to isolated strong convection is observed from 12N to 15N between 126W and 130W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see Tropical Wave section above for information on the potential for low pressure to form in association with a tropical wave later this week into the weekend, well SW of southern Mexico. Fresh to strong N to NE gap winds are noted across the Gulf of Tehuantepec with 8 to 10 ft seas. This activity is ahead of the approaching tropical wave mentioned above in the Tropical Wave section. An altimeter satellite pass from around 0030 UTC confirmed seas to 10 ft approximately 240 nm downstream in gap wind plume from the Gulf of Tehuantepec, likely with a component of longer period southerly swell. Light to gentle breezes are noted elsewhere off southern Mexico, with 4 to 6 ft seas primarily in SW swell. Farther north, a weak ridge is west of the offshore forecast waters of Baja California is maintaining light to gentle breezes, except for possible moderate NW winds funneling along the coast south of Punta Eugenia. Seas are 3 to 5 ft off Baja California in a mix of S and NW swell. For the forecast, the weak pressure gradient over the region will continue to support light to gentle NW winds over the Baja California offshore waters with locally moderate winds along the coast through Sat. In the Gulf of California, mainly gentle to moderate southerly winds are expected through early next week, except for moderate to fresh in the northern Gulf of California through the weekend. Fresh to strong northerly winds are forecast in the Tehuantepec region into Thu, resuming Sun night through early next week. Broad low pressure may move well southwest of the coast of Mexico, possibly bringing fresh winds and rough seas to the Revillagigedo Islands this weekend. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Moderate to fresh offshore winds are noted in the Papagayo region this evening, 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 5 to 8 ft range in southerly swell across the waters, except 8 to 10 ft offshore of Ecuador. For the forecast, the moderate to fresh NE to E winds will continue to pulse across the Papagayo region, pulsing to fresh to strong tonight, and then again Sat night through Mon night. 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 swell from the Southern Hemisphere will continue to propagate across the waters between Ecuador and the Galapagos Islands through Fri. REMAINDER OF THE AREA... See the Special Features section for details on Tropical Storm Felicia. Please see Tropical Waves section above for information on low pressure that is expected to form in association with a tropical wave well south of Mexico later this week. Elsewhere, a broad ridge dominates the waters north of 20N and west of 120W. An altimeter satellite pass from 0230 UTC showed seas to 8 ft, in and area of moderate to fresh NE winds and a mix of NW and S swell, reaching as far south as 29N west of 125W. Gentle to moderate NE winds with 5 to 7 ft seas in mixed swell are prominent north of the monsoon trough and west of 120W, with SE to S winds and southerly swell of 5 to 8 ft south of the monsoon trough west of the Galapagos. For the forecast, little change in marine conditions is expected through the upcoming weekend and into early next week outside of Felicia and the potential low behind it. $$ Christensen