000 AXPZ20 KNHC 291550 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Tropical Storm Irwin is centered near 19.6N 129.1W at 29/1500 UTC, moving west at 15 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Peak seas are 17 ft. Seas of 12 ft or greater are within 90 nm of the center in the NE quadrant, 30 nm SE quadrant, 0 nm SW quadrant and 60 nm NW quadrant. Latest satellite imagery shows little to no deep convection associated with Irwin. Only isolated moderate convection is within 150 nm of the center in the SW quadrant. Winds of 25-35 kt are mostly confined to the northern semicircle. Winds of 20-25 kt extend several hundred nm N and NW of the center. Irwin is forecast to continue in a westward motion, with a slower motion expected later this week. Irwin could become a post-tropical cyclone later today. 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 the Costa Rica/Nicaragua border near 11N86W to 11N95W to 15N107W to 13N120W. The monsoon trough resumes from 09N135W to 08N140W. Scattered moderate convection is noted from 09N to 16N between 89W and 100W, and from 11N to 19N between 104W and 112W. Scattered moderate to strong convection is seen from 06.5N to 09N between 136W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Surface high pressure ridging extends southeastward from a 1027 mb high pressure near 35N141W toward the Baja California Peninsula. The pressure gradient between this high and lower pressure over Mexico is supporting mostly moderate with locally fresh northwest to north winds offshore Baja California. Gentle to moderate winds prevail elsewhere. Seas of 5-8 ft prevail across the offshore waters to the west of Baja California. Winds in the Gulf of California are gentle to moderate along with seas of 1 to 3 ft, except for slighter higher seas of 3-5 ft from the long-period south swell 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 Wed. Northerly swell will raise seas to 8 to 9 ft northwest of Punta Eugenia today and tonight, then subside Thu. Fresh southerly winds are expected Thu in the northern Gulf of California. ...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 along with seas of 4 to 5 ft in long-period south to southwest swell. Near the Galapagos Islands offshore waters, moderate to fresh SE winds with seas of 5-8 ft due to long-period south swell are noted. For the forecast, moderate south to southwest winds will prevail between the coast of Ecuador and the Galapagos Islands tonight through Thu night. Later today into Wed, southerly swell will increase seas to 7 to 9 ft across the Galapagos Island offshore waters, persisting through Thu before gradually subsiding. Elsewhere, light to gentle variable winds will prevail through most of the week with slight to moderate seas in southwest long- period swell. ...REMAINDER OF THE AREA... Please see the Special Features section for details on Tropical Storm Irwin. The pressure gradient between high pressure N of the area and Tropical Storm Irwin is inducing a large area of fresh to strong NE winds extending from north of Irwin all the way to beyond 30N, across much of the area between 120W and 140W. Seas are 6 to 9 ft in the area, except higher closer in to Irwin. Mostly gentle winds are east of 120W from 05N to 20N with seas around 5 ft. Moderate SE winds are found south of 05N. Long-period S swell is crossing the Equator now, and seas are 8 to 9 ft from 03S to the Equator. For the forecast, Tropical Storm Irwin is forecast to weaken to a 30 kt remnant low early Wed morning near 19N134W, then move to near 19N137W early Thu morning, to near 20N140W early Fri morning, and west of the area as a 30 kt remnant low on Fri. Northerly swell will propagate through the open waters well W of Baja California through at least Thu night. Southerly swell in the far southern waters will build seas to 8 to 10 ft today through Wed night. This swell area could travel as far north as 05N between 92W-130W before gradually subsiding Thu into Thu night. $$ Hagen