344 AXPZ20 KNHC 092210 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Sep 9 2021 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 2350 UTC. ...SPECIAL FEATURES... Hurricane Olaf is centered near 22.2N 108.9W at 09/2100 UTC moving NNW at 9 kt. Estimated minimum central pressure is 977 mb. Maximum sustained wind speed is 80 kt with gusts to 100 kt. Satellite imagery continue to show wide banding features containing deep convective activity. This convective activity is observed as the numerous moderate and strong type intensity within 180 nm of the center in the NE and NW quadrant, and scattered moderate and strong convection is within 100 nm in the southern semicircle. Presently maximum seas reach a peak of 23 ft but are forecast to build tonight through Fri as the cyclone approaches southern Baja California. On the forecast track, the center of Olaf will approach the southern coast of the Baja California peninsula during the next several hours, and then move very near or over southern Baja California Sur tonight and on Friday. The hurricane will begin to move westward away from land late Friday or early Saturday. Weakening is expected on Friday after Olaf begins to interact with land. Further weakening is likely over the weekend. Olaf is expected to produce total rainfall amounts of 5 to 10 inches with maximum amounts of 15 inches across portions of southern Baja California Sur through Friday. Swells generated by Olaf are affecting portions of the coasts of southern Baja California Sur, Nayarit, and Sinaloa, and will spread northward along the west coast of Baja California Sur through Saturday. Please read the latest NWS High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPEP5.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMEP5.shtml for more details. ...TROPICAL WAVES... A tropical wave has its axis along 99W north of 04N to inland southeastern Mexico. It is moving westward at 10 to 15 kt. Scattered moderate to strong convection is from 07N-15N between 96W to 101W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from southwest Caribbean to across northern Costa Rica to 10N85W to 10N109W to 07N120W. ITCZ continues from 07N120W to 16N127W. Aside from the convection associated with Hurricane Olaf and the tropical wave, scattered moderate to isolated strong convection is noted from 07N to 14N between 86W to 97W, and between 102W to 110W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on Hurricane Olaf. A weak 1013 mb low is centered near 24N128W. No convection is occurring with this low as it is surrounded by a very dry and stable environment. Latest ASCAT data showed gentle to moderate northwest winds off the Baja California peninsula, except for fresh to strong winds within about 180 nm west of Baja California Sur. Seas over these waters are in the 4-5 ft range in long-period northwest swell. Scattered showers and isolated thunderstorms are occurring in an outer rain band from Olaf along and just inland the coast from Jalisco to Nayarit and numerous moderate strong convection are evident over Baja California Sur over Cabo San Lucas. Hurricane Olaf is forecast to turn toward the northwest by tonight, followed by a slower westward motion Friday night and Saturday. On the forecast track, the center of Olaf will approach southern Baja California Sur today, move near or over the southern part of the peninsula tonight and on Friday, and then move westward away from land Friday night and Saturday. Swells generated by Olaf are beginning to reach portions of the coasts of southern Baja California Sur, Nayarit, and Sinaloa, and will spread northward along the west coast of Baja California Sur through Saturday. Additional strengthening is likely before Olaf nears the southern coast of the Baja California peninsula tonight. Weakening is likely on Friday and through the weekend. In the Gulf of California, light and variable winds will continue through Thu night, then become gentle to moderate southeast winds through Sat. Light to gentle winds will continue across southern Mexico. Fresh to strong gaps winds are expected to develop across the Gulf of Tehuantepec beginning Fri afternoon and continue into the upcoming weekend. An area of low pressure is expected to form in a few days to the south of the southern coast of Mexico. Environmental conditions appear favorable for development of this system, and a tropical depression could form late this weekend or early next week while it moves west-northwestward near the coast of southern and southwestern Mexico. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Moderate to fresh south to southwesterly winds is noted south of the monsoon trough with light and variable winds north of the monsoon trough. Seas are 4-6 ft in the Central American offshore waters and 6-7 ft seas off of Ecuador and the Galapagos Islands due to southwest swell. Satellite imagery shows numerous showers and thunderstorms along and just offshore the coast of Guatemala and El Salvador and scattered showers and thunderstorms mainly along the offshore waters of Nicaragua through Panama. Seas will build to 6-8 ft due to a southwest swell today into Friday. Winds in Papagayo region will increase to fresh speeds Saturday. Moderate to fresh west to southwest winds are expected along the offshore Waters of Costa Rica, Panama, Colombia, Ecuador and Galapagos Islands through the weekend. Strong south to southwest winds are expected over the offshore waters of Guatemala and El Salvador late Sat through late Sun as low pressure develops south of the southern coast of Mexico. Seas in these waters will remain in the 6-7 ft range, except near 8 to 9 ft seas in the region west of Ecuador. Seas offshore Guatemala, Honduras and El Salvador are expected to build to possibly 10 ft during Sat and Sat night due to the expected strong south to southwest winds combining with southwest swell that will be propagating through those same offshore waters. REMAINDER OF THE AREA... Broad high pressure dominates the waters north of the monsoon trough. The gradient between the high and the low pressure to the south in the monsoon trough region is allowing for moderate to fresh north-northeast winds and seas 7 ft south of 21N and E of 123W, and in the vicinity of the 1011 mb low pressure near 15N135W. Moderate southerly winds remain south of the monsoon trough, with seas 7 to 8 ft. Seas 8 to 10 ft due to a southwest swell are noted south of the Equator. Another set of southwest swell will propagate through the waters west of the Galapagos Islands tonight through the upcoming weekend. Seas will range between 8-11 ft through early next week. $$ Torres