000 AXPZ20 KNHC 250719 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Wed Dec 25 2024 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 0700 UTC. ...SPECIAL FEATURES... Significant NW swell: A series of low pressure systems will continue to rotate across the waters north of 30N with associated cold fronts occasionally pushing south of 30N. These low pressure systems will send several rounds of large NW swell that will propagate into the area through the remainder of the week and into next weekend. Currently, seas greater than 12 ft cover the waters roughly west of a line from near Cabo San Lucas to across the Revillagigedo Islands to 07N131W. The large swell has reached the offshore waters of SW Mexico, and will reach just beyond the offshore waters of Central America later today through Fri. Reinforcing swell of 12 ft or greater will move in across the waters mainly north of 20N this weekend. Please see the latest NWS High Seas Forecast issued by the National Hurricane Center at website: https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N85W to 05N97W to 07N106W. The ITCZ extends from 07N106W to 06.5N121W to beyond 07N140W. Scattered moderate convection is noted from 03N to 08N between 84W and 90W, from 05N to 16N between 92W and 106W, from 06N to 09N between 128W and 132W, and from 07N to 10N between 135W and 137W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features Section on significant NW swell that will impact the waters offshore Baja California through the remainder of the week and into the upcoming weekend. Fresh to strong northerly winds prevail in the Gulf of Tehuantepec, with seas of 7 to 9 ft. Elsewhere, mainly gentle to moderate northerly winds prevail across offshore waters of Mexico, including inside of the Gulf of California, except moderate to fresh offshore Baja California from near Cabo San Lazaro northward. Seas are in the 4 to 7 ft east of 99W, while seas are 8 ft or greater west of 99W, including offshore Baja California, up to 13 to 15 ft there. Seas are 3 ft or less inside the Gulf of California. For the forecast, fresh to strong northerly winds in the Gulf of Tehuantepec will gradually diminish through sunrise today. High pressure west of the area will maintain moderate northerly winds pulsing to fresh to strong from Cabo San Lazaro northward through Thu night, with gentle to moderate winds across the remainder of the open waters. Fresh to locally strong winds will be in the northern Gulf of California later this morning through the day as a cold front moves through the region. Significant NW swell will spread southeastward to impact most waters through at least the remainder of the week. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The pressure gradient between a surface ridge extending southward over Central America and the EPAC monsoon trough is supporting fresh to strong NE gap winds in the Papagayo. Seas are 4 to 7 ft across this area. Light to gentle winds prevail elsewhere north of the monsoon trough with seas of 3 to 6 ft. South of the monsoon trough, gentle to moderate S to SW winds prevail. Seas of 3 to 6 ft in S to SW swell are elsewhere outside of the Papagayo region. Scattered showers and thunderstorms are across the offshore waters from near the coast of Panama southwestward including offshore southern Costa Rica. For the forecast, the pressure gradient between high pressure extending southward over Central America and the eastern north Pacific monsoon trough will support fresh gap winds pulsing to strong winds in the Papagayo region through this morning, then moderate to fresh thereafter through the end of the week. Elsewhere, winds will be moderate or weaker with moderate seas through this morning. A surge of at least fresh NW to N winds will move across the offshore waters of Guatemala this afternoon and tonight. Winds may freshen south of the monsoon trough beginning this afternoon. Seas will build today as NW swell moves into the regional waters, decaying into the upcoming weekend. ...REMAINDER OF THE AREA... Please read the Special Features section about large NW swells propagating across the majority of the waters through the next several days. A weakening cold front is over the northern discussion waters from Baja California near 29.5N115W to 25N130W to 23.5N140W. Moderate to fresh winds are immediately north of the cold front. The pressure gradient between high pressure building in from north of and across the weakening boundary southward, and lower pressure in the vicinity of the ITCZ is supporting fresh to strong winds north of the ITCZ to around 20N and west of 130W. Moderate to fresh winds are elsewhere north of the ITCZ to 26N and west of 118W. Across the remainder of the open waters, including south of the monsoon trough/ITCZ, gentle to moderate trades prevail. Aside from the large swell discussed above, seas are mainly in the 5 to 8 ft range. For the forecast, other than the large NW swells discussed in the Special Features section, little change in winds are forecast over the next several days. The weakening cold front mentioned above will gradually dissipate over the northern waters today and tonight. The pressure gradient over the western waters will continue to support fresh to strong trade winds just north of the ITCZ and W of 130W through Thu. Meanwhile, seas of 8 ft or greater will spread SE and cover most of the waters west of roughly 90W this evening into the end of the week. $$ Lewitsky