000 AXPZ20 KNHC 152118 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Sep 15 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 1800UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... The area of low pressure previously located off the southern coast of Mexico is upgraded to Tropical Depression Thirteen-E at 15/2100 UTC. At this time, it is centered near 12.7N 95.4W moving NW at 3 kt. Estimated minimum central pressure is 1007 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Numerous moderate to strong convection is within 120 nm W semicircle of center. Scattered moderate isolated strong convection is noted elsewhere from 10N to 14.5N between 95W and 102W. On the forecast track, the center of the cyclone is expected to approach the southern coast of Mexico within the watch area on Saturday. Gradual strengthening is forecast during the next couple of days, and the depression is forecast to become a tropical storm tonight or Friday. The system is expected to produce rainfall totals of 3-6 inches with isolated maximum totals of 10 inches across coastal portions of the Mexican States of Oaxaca, Guerrero, and Michoacan through Sunday morning. These rains may produce flash and urban flooding, along with isolated mudslides in areas of higher terrain near the coast. Swells generated by the depression are expected to begin affecting portions of the coast of southern Mexico by late Friday and continue into the weekend. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. 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.D. Thirteen-E NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. Southwest of Southwestern Mexico: An area of low pressure located near 15N106.5W or a few hundred miles south-southwest of Manzanillo, Mexico, continues to produce disorganized showers and thunderstorms. Environmental conditions are forecast to become more conducive for development, and a tropical depression is likely to form within the next few days. This disturbance is forecast to meander off the southwestern coast of Mexico through the end of this week, and then begin to move northwestward early next week. Scattered moderate to isolated strong convection is mainly on the W semicircle of the low center from 14N to 17N between 106W and 111W. An area of fresh to strong SW-W winds is S of the low center, covering the waters from 08N to 13N between 102W and 110W. Seas of 8-9 ft are within these winds. The latest Tropical Weather Outlook gives this system a high chance of tropical cyclone formation through 48 hours. Refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details on both areas. ...TROPICAL WAVES... The southern portion of a tropical wave with axis along 82W crosses W Panama, moving west at 5 to 10 kt. Scattered moderate convection is near the southern end of the wave axis, near the Azuero peninsula. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from northern Costa Rica near 10N84W to T.D. Thirteen-E located near 12.7N95.4W to 1007 mb low pressure near 15N106.5W to 1009 mb low pressure near 14N133W to 10N140W. Aside for the convection associated with the tropical depression and the low pressure, scattered moderate and isolated strong convection is noted from 05N to 09N between 80W and 91W. Similar convective activity is from 13N to 17N between 126W and 138W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to the Special Features section for details on recently upgraded T.D. Thirteen-E and a low pressure area located a few hundred miles south-southwest of Manzanillo, Mexico. Recent scatterometer data indicate mainly moderate NW-N winds over the offshore waters of Baja California with seas of 5-7 ft. Light to gentle winds and seas of 1-3 ft prevail in the Gulf of California. Marine conditions S of Cabo Corrientes are related to T.D. Thirteen-E and a the above mentioned low pressure area with a high chance of tropical cyclone formation. For the forecast, T.D. Thirteen-E will strengthen to a tropical storm near 13.3N 96.1W Fri morning, move to 14.1N 97.4W Fri afternoon, 15.1N 98.8W Sat morning, 16.9N 100.5W Sat afternoon, move inland and weaken to a tropical depression near 18.4N 101.9W Sun morning, and dissipate Sun afternoon. High pressure will build across the offshore waters of Baja California supporting moderate to fresh NW-N winds, locally strong near Punta Eugenia at night, and seas of 5-7 ft for the next few days. Gentle to occasionally moderate mainly southerly winds and 1-3 ft seas are expected in the Gulf of California. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate winds are noted north of the monsoon trough, while moderate to fresh S-SW winds prevail south of the monsoon trough. Seas are 5-7 ft in SW swell across the offshore waters, with the exception of 6-8 ft between Ecuador and the Galapagos Islands, as well as offshore Guatemala. A moist and unstable environment interacting with the monsoon trough persists across the area, mainly N of 05N, resulting in showers and thunderstorms. For the forecast, mainly gentle to moderate winds will persist across the offshore forecast waters, with seas of 6-8 ft in SW swell. Winds could increase to moderate to fresh between northern Costa Rica and Guatemala toward the upcoming weekend as a broad area of low pressure develops along the monsoon trough. A very moist and unstable atmospheric environment will help maintain active weather across most of the offshore waters over the next few days. REMAINDER OF THE AREA... Refer to the Special Features section for details on recently upgraded T.D. Thirteen-E and a low pressure area located a few hundred miles south-southwest of Manzanillo, Mexico. High pressure dominates the waters north of the monsoon trough and west of about 120W. The related light pressure gradient is allowing for mostly light to gentle winds over the NW corner of the forecast area. Gentle to moderate winds prevail elsewhere north of the monsoon trough. Seas are 5-7 ft, primarily in long period southerly swell. Moderate to locally fresh southerly winds are south of the monsoon trough along with 5-8 ft seas, outside of T.D. Thirteen-E and a low pressure area located a few hundred miles south-southwest of Manzanillo, Mexico. For the forecast, high pressure will build across the northern forecast waters over the next few days supporting gentle to moderate winds and seas of 4-7 ft. Winds and seas will increase some between the ridge and transient low pressure located along the monsoon trough between 130W and 140W. Additional pulses of cross-equatorial SW swell will continue to propagate across the forecast waters east of 110W. Weather conditions will deteriorate across the offshore waters from Oaxaca to Michoacan due to the presence of a tropical cyclone. $$ GR