000 AXPZ20 KNHC 181551 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sun Sep 18 2022 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 1530 UTC. ...SPECIAL FEATURES... Tropical Storm Madeline is centered near 18.5N 106.9W at 18/1500 UTC moving N at 9 kt. Estimated minimum central pressure is 998 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Scattered to numerous moderate to strong convection is noted from 13N to 20N between 102W and 113W. A broad area of fresh to strong SW-W winds persists S and SE of this tropical cyclone, from 09N to 18N between 101W and 115W. This SW monsoonal wind flow has generated a broad area of high seas to the S and SE of Madeline, that continues to move NE towards the southwestern coast of Mexico. This will maintain very large and rough seas, large dangerous surf and strong rip currents along the coast of Mexico from Oaxaca to Cabo Corrientes through the weekend, and will spread northward and begin to affect the coast of Baja California Sur tonight through early next week. Madeline is moving toward north and is expected to take a slow counter- clockwise turn toward the northwest through Tuesday, and then turn westward. Slight strengthening is forecast for the next day or so. Please consult products from your local weather office for more details. 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 T.S. Madeline NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N85W to 16N95W, then resumes from near 14N113W to a 1012 mb low pres located near 13N129W to 11N140W. Aside from the convection associated with Madeline, scattered moderate convection can be found from 05N to 13N between 78W-96W, and from 08N to 11N between 125W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to the Special Features section for details on T.S. Madeline. A broad ridge extends southeastward across the offshore of Baja California tonight producing moderate NW to N winds. Seas are generally in the 6-7 ft range, except 7-8 ft across the outer offshore of Baja Norte. Light to gentle winds and seas of 1-3 ft prevail in the Gulf of California. Marine conditions S of Cabo Corrientes are dominated by swell being generated by Tropical Storm Madeline. For the forecast, Tropical Storm Madeline will move to 19.5N 107.6W this evening, 20.4N 108.8W Mon morning, 21.0N 110.1W Mon evening, 21.3N 111.3W Tue morning, weaken to a remnant low near 21.5N 112.4W Tue evening, and 21.6N 113.8W Wed morning. Madeline will change little in intensity as it moves to 21.4N 116.9W early Thu. The ridge will remain in place across the offshore waters of Baja California through the weekend and maintain moderate. Gentle to occasionally moderate mainly southerly winds and 1-3 ft seas are expected in the Gulf of California. Marine conditions will continue to deteriorate between Los Cabos and Cabo Corrientes today as T.S. Madeline moves northward. Another area of low pressure is forecast to form south of the southern coast of Mexico Tue through Wed. Some gradual development is possible thereafter while the disturbance moves generally west-northwestward off the coast of southwestern Mexico. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate W-SW winds prevail south of the monsoon trough, except for an area of fresh SW winds well offshore of Costa Rica and the Papagayo region. Light and variable winds are north of the trough from the Gulf of Papagayo region to Guatemala coastal waters. Seas are 6-8 ft in SW swell across the offshore waters, with areas of 8-9 ft across the far outer offshore waters W of 87W. A moist and unstable environment interacting with the monsoon trough persists across the area. For the forecast, mainly gentle to moderate winds will persist across the offshore forecast waters, with seas of 6-9 ft in SW swell through Sun. A very moist and unstable atmospheric environment will help maintain active weather across most of the offshore waters over the next few days. An area of low pressure could form between Papagayo and Tehuantepec during the next few days. Environmental conditions are forecast to be conducive for some gradual development while the system moves west- northwestward offshore the coast. REMAINDER OF THE AREA... Refer to the Special Features section for details on T.S. Madeline. High pressure extends south and southeastward across the waters north of the monsoon trough and west of about 118W, centered on a 1029 mb high near 47N149W. The pressure gradient between this system and the monsoon trough supports an area of moderate to fresh NE winds from 15N to 23N W of 128W. Seas are 6-8 ft within these winds. Gentle to moderate winds prevail elsewhere north of the monsoon trough. Moderate to locally fresh southerly winds are south of the monsoon trough along with 5-8 ft seas, outside of T.S. Madeline. Cross equatorial SW swell continues to move into the region and is maintaining seas of 6-7 ft to the south of the monsoon trough and west of the Galapagos Islands. For the forecast, high pressure will continue to dominate the northern forecast waters. A weak cold front is forecast to enter the discussion area today, extending roughly from 30N127W to 28N134W by tonight, then to 30N124W to 24N140W Mon night. Seas of 8-10 ft in northerly swell will follow the front reaching the waters N of 27N and W of 126W by Mon morning. Additional pulses of cross-equatorial SW swell will continue to propagate across the forecast waters east of 130W. As T.S. Madeline turns westward along about 21N Tue through Wed, E to NE swell will spread ahead of it. $$ ERA