000 AXPZ20 KNHC 222157 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sun Oct 22 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 1800 UTC surface analysis and satellite imagery through 2130 UTC. ...SPECIAL FEATURES... Tropical Storm Norma is centered near 24.9N 109.4W at 22/2100 UTC, moving northeast at 3 kt. Estimated minimum central pressure is 987 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Peak seas are around 21 ft. Scattered moderate to isolated strong convection is noted from 24N to 27N between 108W and 110W. Norma is expected to turn toward the east-northeast later today and tonight. On the forecast track, the center of Norma is forecast to approach the west coast of mainland Mexico today and move inland within the tropical storm warning area tonight or early Monday. Little change in strength is forecast today, and Norma is expected to move over the west coast of mainland Mexico as a tropical storm. Rapid weakening is anticipated once Norma moves inland over mainland Mexico. Norma will produce rainfall totals of 6 to 12 inches with maxima of 18 inches across Sinaloa into Monday. These rains will produce flash and urban flooding, along with mudslides in areas of higher terrain. Swells generated by Norma will continue to affect the coast of southwestern and west- central Mexico and Baja California Sur for the next day or two. These swells are likely to cause life- threatening surf and rip current conditions. Please consult products from your local weather office. Please consult products from your local weather office and 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 Norma NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. Newly upgraded Tropical Storm Otis is centered near 10.3N 96.9W at 22/2100 UTC, moving north-northwest at 4 kt. Estimated minimum central pressure is 1004 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Peak seas are around 11 ft. Numerous moderate to strong convection is noted from 09N to 14N between 94W and 101W. Otis is expected to continue moving slowly toward the north- northwest through Tuesday. A slow northwestward motion is forecast to begin by Wednesday morning. Some slight strengthening is forecast during the next couple of days. Heavy rainfall may impact coastal areas of southern Mexico from Oaxaca to Guerrero later this 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 Eighteen-E NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from the coast of Costa Rica near 11N86W to 09N110W to low pres near 10N123W 1008 mb to 07N126W. The ITCZ extends from 07N126W to beyond 05N140W. Scattered moderate convection is noted from 03N to 11N between 78W and 90W, from 06N to 11N between 102W and 132W and from 03N to 07N W of 139W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the SPECIAL FEATURES section above for more details on Tropical Storm Norma and Tropical Storm Otis. The pressure gradient between the subtropical ridge to the west of the Baja California Peninsula and Norma is supporting fresh to strong N to NW winds along the Baja Peninsula offshore waters. Seas are 8 to 9 ft in mixed swell N of Cabo San Lazaro. Seas are 8 to 15 ft southward to the entrance of the Gulf of California and Jalisco offshore waters. The latest scatterometer data depicted light to gentle winds in the Gulf of California N of 27N. Seas are 3 to 5 ft. The remainder SW Mexican offshore waters have light to gentle variable winds prevailing and seas to 9 ft in mixed swell. For the forecast, Norma will move to 25.1N 108.9W Mon morning, move inland and weaken to a tropical depression near 25.5N 108.1W Mon afternoon, and dissipate Tue morning. Otis will move to 10.7N 97.0W Mon morning, 11.6N 96.9W Mon afternoon, 12.7N 96.9W Tue morning, 13.5N 97.2W Tue afternoon, 13.9N 97.6W Wed morning, and 14.2N 97.8W Wed afternoon. Otis will change little in intensity as it moves near 14.5N 98.0W Thu afternoon. Elsewhere, strong winds will persist through Mon morning across the Baja California offshore waters N of Cabo San Lazaro. NW swell across the Baja California offshores along with swells generated by Norma will continue to result in confused and hazardous seas at the entrance of the Gulf of California through tonight. This swell will subside by Mon. A new set of NW swell will enter the offshores of Baja California Norte N of Punta Eugenia Mon night and subside Wed morning. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Please see the SPECIAL FEATURES section above for more details on Tropical Storm Otis. Outside of Otis, scatterometer data showed moderate winds pulsing in the Gulf of Papagayo. Meanwhile, light to gentle winds persist elsewhere north of the monsoon trough. South of the monsoon trough, gentle to moderate S winds are noted. Seas are 8 to 11 ft in the Guatemala and El Salvador offshore waters due to Otis. Seas are 6 to 8 ft west of the Galapagos Islands due to mostly NW swell. Otherwise, seas range 5 to 7 ft within NW and SW swell. Scattered showers and thunderstorms continue across the offshore waters of Colombia, Panama, Costa Rica, and Nicaragua. For the forecast, Otis will move to 10.7N 97.0W Mon morning, 11.6N 96.9W Mon afternoon, 12.7N 96.9W Tue morning, 13.5N 97.2W Tue afternoon, 13.9N 97.6W Wed morning, and 14.2N 97.8W Wed afternoon. Otis will change little in intensity as it moves near 14.5N 98.0W Thu afternoon. Elsewhere, winds will increase to locally fresh across the South America and Galapagos Islands offshore waters briefly on Mon. Otherwise, gentle to moderate winds will prevail across the area through most of the week. Mixed swell will bring seas 6 to 8 ft across most of the waters through most of the week. ...REMAINDER OF THE AREA... Please see the SPECIAL FEATURES section above for more details on Tropical Storm Norma and Tropical Storm Otis. Surface ridging extends across the northern forecast waters, N of 16N and W of 120W. This is supporting gentle to moderate N to NE winds N of the monsoon trough and W of 120W. S of the monsoon trough, gentle to moderate S to SW winds are noted. Large NW swell continues to propagate across most of the waters between 94W and 130W with 8 to 10 ft seas. For the forecast, Otis will move to 10.7N 97.0W Mon morning, 11.6N 96.9W Mon afternoon, 12.7N 96.9W Tue morning, 13.5N 97.2W Tue afternoon, 13.9N 97.6W Wed morning, and 14.2N 97.8W Wed afternoon. Otis will change little in intensity as it moves near 14.5N 98.0W Thu afternoon. Elsewhere, a weak pressure pattern will support mainly gentle to moderate winds across the open waters through today. Winds may increase moderate to fresh on Mon as high pressure builds N of the area and tightens the pressure gradient. Meanwhile, a new set of NW swell is forecast to spread S of 30N to the E of 130W by Mon, potentially building seas to 10 ft N of 26N. $$ AReinhart