000 AXPZ20 KNHC 100257 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Fri Sep 10 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 0000 UTC surface analysis and satellite imagery through 0250 UTC. ...SPECIAL FEATURES... Hurricane Olaf is centered near 23.0N 109.6W at 10/0300 UTC moving NW at 10 kt. Estimated minimum central pressure is 974 mb. Maximum sustained wind speed is 85 kt with gusts to 105 kt. Numerous moderate scattered strong convection within 45 nm of the center. Scattered moderate isolated strong convection elsewhere from 21N to 25W between 106W and 111W. Olaf is forecast to move very near or over the southern portion of Baja California Sur tonight and Friday. Heavy rains associated with Olaf are expected across portions of southern Baja California Sur through Friday. This will pose a threat of significant and life-threatening flash flooding and mudslides. 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... The axis of a tropical wave is near 86W/87W north of 02N, moving west at 10 to 15 kt. Scattered moderate and isolated strong convection is noted from 07N to 14N between 84W and 90W. This tropical wave will be monitored over the next several days for the potential for tropical cyclogenesis. The axis of a tropical wave is near 99W/100W north of 03N to inland southwestern Mexico, moving westward at 10 to 15 kt. Scattered moderate isolated strong convection is noted from 07N to 14N between 96W to 101W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N86W to 11N93W to 08N122W to 09N130W. Aside from the convection discussed in the tropical waves section, scattered moderate to isolated strong convection is noted from 07N to 14N between 90W and 96W. Scattered moderate convection is noted from 08N to 12N between 101W and 112W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on Hurricane Olaf. Aside from Olaf, a weak pressure pattern prevails. Gentle to moderate winds are noted west of Baja California as well as over the Gulf of Tehuantepec. Light to gentle winds prevail elsewhere. Seas are in the 4-6 ft range over the open waters off Mexico, and 3 ft or less over the Gulf of California. In the Gulf of California, light and variable winds will continue through tonight, then become gentle to moderate southeast winds through Sat. Fresh to strong gaps winds are expected to develop across the Gulf of Tehuantepec beginning Fri afternoon and continue into the upcoming weekend. Hurricane Olaf will move inland to 23.9N 110.7W Fri morning, 24.6N 112.3W Fri evening, weaken to a tropical storm near 24.8N 113.6W Sat morning, 24.4N 114.8W Sat evening, become post- tropical and move to 23.7N 115.9W Sun morning, and weaken to a remnant low near 23.0N 117.2W Sun evening. A tropical wave is in the far eastern Pacific waters. Low pressure is forecast to develop in association to this tropical wave this weekend off the southern coast of Mexico. Subsequent gradual development of this system will be possible, and a tropical depression could form late this weekend or early next week while it moves west-northwestward or northwestward near the coast of southern and southwestern Mexico. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Gentle to moderate south to southwesterly monsoon flow prevails south of the monsoon trough with light winds north of the monsoon trough. Seas are in the 4-6 ft range across the Central American offshore waters, with 6-7 ft seas over the waters between Ecuador and the Galapagos Islands due to southwest swell. Fresh to 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 offshore Guatemala, Honduras and El Salvador are expected to build this weekend due to strong south to southwest winds combining with southwest swell that will be propagating through those same offshore waters. These seas will begin to slowly subside early next week. REMAINDER OF THE AREA... Low pressure of 1011 mb is centered near 15N136W. Isolated moderate convection is within 30 nm west of the low. Recent ASCAT pass indicated moderate to fresh winds north of the low, with gentle to moderate winds south of the low. Another area of low pressure is centered near 24N129W. This is a weaker low with a pressure of 1014 mb, supporting gentle winds around the low. Light to gentle winds prevail elsewhere north of 10N. Gentle to moderate winds prevail south of 10N. Seas are in the 5-6 ft range in the vicinity of the low, and 4-5 ft elsewhere north of 10N. South of 10N, seas are in the 5-7 ft range, locally to 8 ft. A 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. $$ AL