000 AXPZ20 KNHC 011005 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Fri Oct 1 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 0945 UTC. ...TROPICAL WAVES... A tropical wave has its axis extending along 95W from 04N to 16N. It is moving westward at 10-15 kt. from a 1010 mb low near 09N95W to the Gulf of Tehuantepec region. Isolated showers and thunderstorms are noted within 60 nm either side of axis near where it crosses the monsoon trough. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 10N84W to a 1010 low pressure near 09N94W to 12N107W to 14N126W and to 11N140W. Scattered moderate to isolated strong convection is within 120 nm north of the trough between 135W-140W, within 60 nm south of the trough between 88W-92W and between 138W-140W. Scattered moderate convection is within within 60 nm north of the trough between 118W-12$W and within 60 nm south of the trough between 127W-138W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Scattered moderate to isolated strong convection within 90 nm southwest of Manzanillo, Mexico is associated with a broad area of low pressure that is located a couple of hundred nautical miles west-southwest of Manzanillo. Winds with the low pressure are mainly gentle to moderate, and nearby seas are 4-6 ft due to a southwest swell. Gentle to moderate northwest winds are noted offshore of Baja California, while mainly gentle to moderate winds prevail elsewhere offshore of Mexico. Northwest swell is producing seas of 6-8 ft west of Baja California, with the highest seas north of Punta Eugenia. Seas are mainly 4-6 ft elsewhere in mixed northwest and south long-period swell, except 3 ft or less in the Gulf of California north of the entrance area. For the forecast, some slow development is possible with the low pressure area located a couple of hundred nautical miles west- southwest of Manzanillo through early today as it moves west- northwestward before it reaches an area of stronger upper- level winds. Moderate northwest-north winds offshore of Baja California will diminish by the end of the week. Moderate to fresh gap winds may develop in the Gulf of Tehuantepec this weekend, increasing to fresh to strong by Sun night and continue to pulse during the night time hours through early next week. Otherwise, light to gentle winds will prevail. Large northwest swell propagating southeast and offshore of Baja California will subside by the end of the week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Light to gentle east-southeast winds are north of the monsoon trough, with moderate south-southwest winds south of the monsoon trough. Seas are mainly in the 4-6 ft due to a south to southwest long-period swell. For the forecast, winds in the Papagayo region will pulse to moderate Fri night speeds through Sat night. Otherwise, light to gentle winds will prevail north of the monsoon trough, with mainly moderate south to southwest winds south of the monsoon trough. A moderate cross-equatorial southwest swell will propagate through the regional waters during the next several days. REMAINDER OF THE AREA... A tight gradient between strong high pressure centered north of the area and lower pressure found in the sub-tropical region is inducing fresh to strong northeast to east winds from 13N to 24N west of about 123W. This area of winds is being further enhanced by a small low pressure system of 1010 mb that is embedded within the monsoon trough near 13N131W. Seas within this area of winds have reached the range of 8-10 ft. By this evening, the gradient is forecast to slacken enough to allow for the winds to diminish to mainly fresh speeds, however, the seas of 8-10 ft will continue due to long-period north swell. These marine conditions are expected to last through late Sat. Mainly moderate to locally north to northeast winds continue elsewhere north of the convergence zone, with moderate southerly flow south of the monsoon trough. Seas are mainly 5-7 ft across the remainder of the open waters due to long-period northwest to north swell mixing with south swell. Long-period northwest to north swell over the northeast part of the area producing peak seas of 8 ft north of 22N and between 116W-125W will decay by early Fri morning. For the forecast, reinforcing fresh northerly swell will induce seas back up to around 8 ft near 30N between 125W-137W into the weekend. Gentle to moderate north to northeast winds east of 123W will become generally light to gentle in speeds late today and through the weekend as high pressure north of the area weakens. The 1010 mb low pressure near 13N131W will be within atmospheric conditions conducive for it to undergo slow development during the next several days, and a tropical depression could form over the weekend or early next week while if moves generally westward. $$ Aguirre