138 AXPZ20 KNHC 290400 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Tue Aug 29 2023 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 0345 UTC. ...SPECIAL FEATURES... Tropical Storm Irwin is centered near 19.3N 125.7W at 29/0300 UTC, moving west-northwest at 13 kt. Estimated minimum central pressure is 999 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Peak seas to Seas to 15 ft are within 90 nm of the center in the N semicircle. Latest satellite imagery shows scattered moderate to isolated strong within 60 nm of the center in the NE quadrant and 120 nm in the NW quadrant. Irwin is forecast to turn toward the west tonight. Irwin is then expected to continue heading generally westward for the next several days. Only small changes in intensity are expected for the next day or so. Slow weakening is likely after that and Irwin could become post-tropical by mid-week. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest Irwin NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwest Colombia to 11N86W to 14N95W to 15N105W to 18N113W. It resumes at south of Irwin near 12N125W to 08N136W. The ITCZ extends from 08N136W to 08N140W. Scattered moderate convection is within 120 nm south of the ITCZ. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Surface ridging extends toward the Baja California Peninsula anchored by a 1025 mb high pressure center that is north of the area near 33N140W. The pressure gradient between this high and lower pressure over Mexico is supporting mostly gentle to moderate northwest to north winds, with fresh winds near the coast north of Punta Eugenia. Gentle to moderate winds prevail elsewhere. Seas of 4-6 ft prevail across the Mexican offshore waters. Winds in the Gulf of California are light to gentle along with seas to 3 ft, except higher seas of 4-6 ft from the long- period south are near the southern tip of Baja California. For the forecast, moderate to fresh NW winds off Baja California north of Cabo San Lazaro will persist through mid-week. Northerly swell will raise seas to around 8 or 9 ft north of Punta Eugenia by Tue, then subside by Thu evening. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle south to southwest winds prevail across most of the offshore waters N of 02N with seas to 4 ft in long-period south to southwest swell. In the Ecuador and Galapagos Islands offshore waters, moderate to fresh south winds with seas of 4-5 ft due to long-period south swell are noted. For the forecast, gentle to moderate south to southwest winds and moderate seas will continue between the coast of Ecuador and the Galapagos Islands through Thu night. By Wed, an increase of southerly swell and seas to 7 ft could impact the Galapagos Island offshore waters. Elsewhere, light to gentle variable winds will prevail through most of the week with slight to moderate seas in southwest swell. ...REMAINDER OF THE AREA... Please see the Special Features section for details on Tropical Storm Irwin. The pressure gradient between surface ridging north of about 20N and lower pressures associated with Tropical Storm Irwin and low pressure embedded in the monsoon trough west of 140W is maintaining moderate to fresh north to northeast winds mainly north of the monsoon trough to 23N and west of 120W. Seas are 5-7 ft. Gentle to moderate northeast to east winds and slight to moderate seas remain north of 15N and west of 125W. Gentle to moderate southwest winds are elsewhere south of the monsoon trough with seas of 5-7 ft. For the forecast, Tropical Storm Irwin will weaken to a tropical depression near 19.1N 133.2W Wed morning, move to near 19.1N 135.4W Wed evening, become a remnant low and move to 19.3N 137.2W Thu morning, and to near 19.4N 138.5W Thu evening. The remnant low will change little in intensity as it moves to near 19.6N 140.8W late Fri. Northerly swell will propagate through the open waters W of the Baja California offshore waters tonight through at least Thu night. Southerly swell in the far southern waters could see 8 ft seas starting tonight. This swell area could travel as far north as 05N between 92W-120W through late Thu. $$ Aguirre