000 AXPZ20 KNHC 090916 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Wed Nov 09 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northern Costa Rica near 10N86W to 12N91W to 09N107W and to 10N120W. The ITCZ extends from 10N120W to 10N130W to beyond 09N140W. Scattered moderate to isolated strong convection is within 30 nm north of the ITCZ between 127W-128W. Scattered moderate convection is within 30 nm of the trough between 99W-101W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A shear line extends from near 30N118W to 26N124W and to 23N140W. A cold front behind the shear line extends from extreme northern Baja California southwestward to 27N126W and to 26N140W. Fresh to strong SW winds have developed ahead of the cold front over the northern Gulf of California along with seas of 5-6 ft. Seas in the range of 8-12 ft offshore Baja California Norte are due to long- period swell, and seas of 6-9 ft are off Baja California Sur. In the Gulf of Tehuantepec, strong to locally near gale force N to NNE winds prevail, along with seas of 7-9 ft. Moderate NW winds are off Cabo Corrientes. Gentle wind speeds prevail elsewhere along with seas of 4-5 ft due to primarily a NW swell. For the forecast, the shear line will weaken as it moves across the waters west of Baja California today, and weaken to a trough by Wed evening when it reaches from 27N109W to 24N132W, and reach from 24N107W to 22N113W to 22N130W by Thu evening and dissipate soon afterwards. The cold front will follow in behind the shear line, and weaken as it moves across the Gulf of California and Baja California through Thu night. The NW swell following in the wake of this front will continue to build seas over the Baja California offshore waters through early Thu. Seas up to 9 ft will reach as far south as the Cabo San Lucas offshore waters Thu and Thu night, with seas building to 12 ft N of Punta Eugenia through Wed. The fresh to strong S to SW winds in the northern Gulf of California ahead of the shear line will diminish to fresh speeds early this afternoon. Winds will become gentle to moderate, N to NE in direction, in the far northern part of the Gulf this afternoon behind the front as it passes through that part of the Gulf. In the wake of the shear line and cold front, fresh NW winds are expected across most of the Gulf of California tonight through Fri night. Strong to near gale force NW winds over the Gulf of Tehuantepec will persist through Wed night. Winds will gradually diminish on Thu as high pressure over the Gulf of Mexico weakens and shifts eastward. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to locally fresh S-SW winds remain south of the monsoon trough, with light to gentle winds N of the monsoon trough. Seas are 4-6 ft across the Central America offshore waters. Otherwise, gentle S winds with seas to 4 ft are noted across the Ecuador and Galapagos Islands offshore waters. Scattered showers and thunderstorms are over the waters well offshore of Guatemala through Nicaragua, but near the coast of Costa Rica. For the forecast, moderate to locally fresh SW winds will prevail south of the monsoon trough through the rest of the week. Light to gentle variable winds will persist elsewhere. Slight to moderate seas can also be expected. Scattered showers and thunderstorms will continue through Thu offshore waters from Guatemala to Nicaragua, but near the coasts of Costa Rica and Panama. REMAINDER OF THE AREA... A shear line extend extends from near 30N118W to 26N124W and to 23N140W, while a cold front behind the shear line extends from extreme northern Baja California southwestward to 27N126W and to 26N140W. Moderate to fresh W to NW winds are between the shear line and the cold front, while fresh NW winds are west of the cold front mainly N of 28N. Seas of 8-12 ft in NW long- period swell are between the shear line and the cold front, while seas of 10-15 ft in NW to N long-period swell are NW of the cold front as depicted by recent altimeter data passes over that part of the area. The highest seas are present as far south as 22N. High pressure ridging remains across the waters south of the front and north of the ITCZ, with mostly gentle winds from 15N to 24N. To the south of 20N, seas are in the 5-6 ft range across much of the area. The exception is from 05N to 10N, to the east of 105W, where fresh SW winds south of the monsoon trough are inducing slighter higher seas of 6-7 ft. For the forecast, the shear line will push east-southeastward and weaken to a trough as it moves across the waters west of Baja California tonight through Thu evening and dissipate soon afterwards. The cold front will continue to move east- southeastward and weaken as it moves across the Gulf of California and Baja California through Thu night. Fresh to strong west-northwest to northwest winds behind the cold front will become moderate to fresh northwest to north winds late tonight and Wed. The cold front is expected to weaken to a shear line or trough by that time in an E to W orientation roughly along 22N and east of about 130W, followed by moderate to fresh NW to N winds and decaying NW swell, with subsiding seas of 8-9 ft. Large NW to N swell will continue to propagate S across the area. Seas of 12 ft or higher will propagate as far south as 26N today, with 8 ft seas propagating as far south as 09N by Thu. Across the northern part of the area, winds and seas will slowly diminish on Thu as high pressure shifts eastward in response to a cold front that approaches the NW corner of the area Thu night. Looking ahead, the next set of long-period NW swell is expected to move into the far northwest part of the discussion area during the upcoming weekend. Elsewhere, moderate to locally fresh winds will remain south of the monsoon trough. $$ Aguirre