000 AXPZ20 KNHC 240908 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Thu Jun 24 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 0600 UTC surface analysis and satellite imagery through 0820 UTC. ...SPECIAL FEATURE... Gale Warning: A 1008 mb low is analyzed near 12.5N98W associated with a tropical wave that extends from 04N to coastal Mexico along 98W, moving west 10 to 15 kt. Scattered to locally numerous moderate to strong convection is noted from 11.5N northward to the coast between 91W AND 104W, and extends northward within 180 nm of the Mexican coast to 21N. Environmental conditions are conducive for development of this system, and a tropical depression is expected to form during the next couple of days as the disturbance moves west-northwestward at about 10 mph. A gale warning has been issued in anticipation of gale force winds developing by 1200 UTC Fri. This system is expected to be near the coast of southern or southwestern Mexico this weekend, and interests in those areas should monitor its progress for development. In addition to strong winds and large seas near this system, the main weather impact will be the potential for heavy rainfall and flooding along the mountainous coastline from Guerrero to Jalisco. This is in the same general area that experienced heavy rainfall from Dolores a few days ago. ...TROPICAL WAVES... A second tropical wave extends from 05N to 16N along 111W, moving west 10 kt. Scattered moderate isolated strong convection is noted from 10N to 15N between 103W and 112W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N74W to 08N82W to low pres 1008 mb near 12.5N98W to low pres 1013 mb near 13.5N107W to 09N117W to 11N122W. The ITCZ extends from 11N122W to 13N130W to beyond 08N140W. In addition to the convection mentioned in the Special Features and Tropical Wave sections, scattered moderate to strong convection is from 02N to 09N E of 84W, and from 04N to 09N between 90W and 105W. Scattered moderate convection is from 07N to 12N between 113W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A 0150 UTC ASCAT pass recently showed E to SE winds of 20-25 kt within 90 nm E of the 1008 mb low currently near 12.5N98W, with these strong E winds extending all the way to coast near Puerto Angel. Seas are assumed to be around 8 ft and building within this area of strong winds accompanying this low and tropical wave. These deteriorating marine conditions will shift westward tonight through Thu across the near and offshore waters of Oaxaca as the low pressure gradually becomes better organized. Farther north to 18N, gentle to moderate E to SE breezes prevail, with 4 to 6 ft seas in a mix of SW and NW swell. A gale warning is in effect for the offshore waters from western Oaxaca to Michoacan effective Thu night and Fri. This is related to the developing low pressure currently well south of the Gulf of Tehuantepec. There is a high chance this low will develop into a tropical depression over the next couple of days. If this happens, gale conditions or higher are possible off Colima, Jalisco and south of Cabo San Lucas Fri night through Sun, then approaching Socorro Island Mon. Gentle to locally moderate NW winds prevail offshore of Baja California tonight with seas of 4-5 ft. Similar southerly winds prevail inside the Gulf of California. High pressure will begin to build across the area from the NW Thu into the weekend to freshen the wind flow across these waters. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Light to gentle easterly breezes prevail N of the monsoon trough along 10N tonight, while light to gentle SW to W winds prevail S of the trough. Slight to moderate seas of 5-7 ft in SW swell prevail. For the forecast, fresh NE gap winds will pulse through the Gulf of Papagayo tonight and Thu. Moderate SW swell will impact the waters off Ecuador, Colombia and into western Panama and Costa Rica, through Fri before fresh SW swell arrives Fri night through Sat to raise seas to 6-8 ft through the weekend. Elsewhere, light to gentle breezes will persist. REMAINDER OF THE AREA... A high pressure ridge extends across the waters north of 20N and west of 125W and is centered on a 1025 mb high near 39N139W. The pressure gradient between this area of high pressure and lower pressure within the monsoon trough/ITCZ is supporting gentle to locally moderate winds north of 10N and west of 125W. A broad trough is analyzed 128W to 132W, where winds are 15-20 kt within 120 nm to the north of the trough and seas are 7-8 ft. Winds and seas will diminish through the latter part of the week in this area. $$ Stripling