000 AXPZ20 KNHC 130927 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Jul 13 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 0900 UTC. ...SPECIAL FEATURES... A broad area of low pressure located NEAR 11N105.5W or over 600 miles south of Cabo Corrientes, Mexico is producing disorganized showers and thunderstorms, mainly to the north of its center. Scattered moderate to isolated strong convection is noted from 11N to 14N between 105W and 108W. Environmental conditions are favorable for development of this system, and a tropical depression is likely to form later this week well offshore of the southwestern coast of Mexico while the low moves westward to west-northwestward at 10 to 15 kt. The latest Tropical Weather Outlook gives this system a medium chance of tropical cyclone formation within the next 48 hours. ...TROPICAL WAVES... A tropical wave extends along 94W from 02N northward into the Gulf of Tehuantepec where a cluster of moderate to isolated strong convection is noted. The wave is moving W at around 10 to 15 kt. Scattered moderate isolated strong convection is also noted E of the wave axis from 06N-08N between 90W-94W, and N of 14N between 95W-100W. Another tropical wave is along 105W/106W from 04N to 15N. The low pressure mentioned in the Special Features section is along the wave axis. The axis of a third tropical wave extends along 132W from 04N to 18N, moving W at around 10 to 15 kt. Scattered moderate convection is where the wave meets the monsoon trough from 09N to 11N between 128W and 132W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from western Colombia near 08N76W to 09N94W to 1008 mb low pres located near 11N105.5W to a 1010 low pressure situated near 13N124W to 10N134W. The ITCZ extends from 10N134W to 09N140W. Aside from the convection related to the tropical waves and special feature described above, clusters of moderate to isolated strong convection are seen N of 05N E of 81W, including the Gulf of Panama. This convective activity is also affecting parts of Panama and extends into the Caribbean Sea. The southern end of a tropical over the Caribbean Sea, along 80W, combined with the monsoon trough, supports this strong convection. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak ridge dominates the offshore forecast waters of Baja California producing gentle to moderate NW-N winds and seas of 4-6 ft. Light to gentle winds are noted elsewhere across the offshore waters of Mexico, except in the Tehuantepec region where fresh to locally strong N-NE winds are noted per scatterometer data, with seas to 8 ft. For the forecast, a surface ridge will continue to extend over the waters W of Baja California peninsula over the next several days. Gentle to moderate NW-N winds will prevail the remainder of the week. Light to gentle breezes will persist off southern Mexico through Fri. In the Gulf of California, mainly gentle to moderate southerly winds are expected over the next several days, with the exception of moderate to locally fresh SE-S winds, with seas of 3-5 ft in the northern part of the Gulf. Fresh to strong northerly winds are forecast in the Tehuantepec region through Thu, with seas building up to 9 or 10 ft. An area of low pressure is forecast to develop south of the Gulf of Tehuantepec late this week and move westward at 10 to 15 mph, well offshore of the southern coast of Mexico. Environmental conditions are expected to be favorable for gradual development, and a tropical depression is likely to form this weekend. Based on latest Tropical Weather Outlook, this system has a high chance of tropical cyclone formation through 5 days. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Fresh to locally strong NE-E winds and seas to 8 ft are noted in the Papagayo region. Light winds are north of the monsoon trough with gentle to moderate winds south of the monsoon trough. Seas mostly range 5 to 8 ft, with 8 to 9 ft seas between Ecuador and the Galapagos Islands. For the forecast, fresh to locally strong NE-E winds will continue to pulse across the Papagayo region through today, and then again Wed through Thu. Elsewhere, gentle to moderate southerly flow will prevail south of 10N through the week, with light to gentle breezes north of 10N. Large swell from the Southern Hemisphere will continue to propagate across the waters between Ecuador and the Galapagos Islands through at least Wed. Seas will continue to be 8 to 9 ft in this area, reaching as far north as the offshore waters of western Panama. REMAINDER OF THE AREA... A surface ridge dominates the northern forecast waters and extends from a 1030 mb high pressure located near 40N140W. Recent satellite derived wind data show moderate to locally fresh NE-E winds N of the monsoon trough to about 20N between 118W-134W. The pressure gradient between the ridge and a low pressure along the monsoon trough near 13N124W supports these winds. Fresh NE and seas to 8 ft are observed over the far NW corner of the forecast area. Two tropical cyclones are forecast to develop across the forecast region, one later this week and the second one during the upcoming weekend. $$ GR