000 AXPZ20 KNHC 130322 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sun Dec 13 2020 Tropical Weather Discussion for the eastern Pacific Ocean from the Equator to 32N, east of 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 0300 UTC. ...SPECIAL FEATURES... Gulf of Tehunatepec Gale Warning: The next gap winds event over the Tehuantepec region is expected late Mon into Mon night. Winds are forecast to briefly reach gale force by Mon evening with seas building to 11 ft. Building high pressure across the western Gulf of Mexico and the eastern slopes of the Sierra Madre mountains in Mexico will support this event. Looking ahead, gale conditions and building seas to 11-12 ft are forecast again in the Tehuantepec area Wed night through Thu night as another cold front moves across the Gulf of Mexico. Please, read the latest NWS High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from a 1009 mb low pressure over northern Colombia near 09N74W to 05N80W to 06N100W to 09N121W. The ITCZ continues from 09N121W to beyond 07N140W. Scattered moderate convection is noted from 10N to 12N between 117W and 122W, and from 08N to 10N between 130W and 135W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A Gale Warning has been issued for the Tehuantepec region. Please, see the Special Features section for more details. A ridge dominates the offshore forecast waters of Baja California. The pressure gradient between the ridge and a meandering trough over the Gulf of Baja California supports fresh to strong NW-N winds N of 28N E of 120W, with seas of 8 ft. These marine conditions winds will persist over the next 48 hours. A new set of long period NW swell will reach the waters N of Punta Eugenia on Mon building seas to 8-11 ft. By Mon evening, this swell event will propagate across the waters N of Cabo San Lazaro. Gulf of California: Building high pressure over the Great Basin region in U.S. will bring an increase in winds and seas across the Gulf of California late tonight into Sun morning. Fresh to strong NW-N winds will spread across much of the Gulf from north to south, with seas building to 8 ft over the north waters by Sun afternoon, and then over the central waters by Sun evening. Wind and seas will diminish early on Mon morning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Moderate to fresh NE-E winds will prevail in the Papagayo region over the next several days with seas of 5-7 ft tonight and Sun, then 4-6 ft the remainder of the forecast period. Gentle to moderate northerly winds are expected in the Gulf of Panama with similar sea heights. Elsewhere, gentle to moderate winds will prevail on either side of the monsoon trough. Seas of 5-8 ft in SW swell between Ecuador and the Galapagos Islands will gradually subside to 4-6 ft by late Mon. REMAINDER OF THE AREA... High pressure of 1024 mb located near 30N127W extends a ridge SE across the northern forecast waters to near Cabo Corrientes. The pressure gradient between the ridge and lower pressures in the vicinity of the ITCZ/Monsoon Trough is supporting a large area of fresh to locally strong trade winds 09N to 16N W of 130W, and from 12N to 16N between 120W and 130W based on latest scatterometer data. Seas are in the 8-9 ft range. These winds will remain in place for the next several days as high pressure persists north of the area. A new set of long period NW swell will begin to propagate across the northern forecast waters tonight, covering most of the area N of 20N W of 115W, and from 10N to 20N W of 125W by late Mon. Seas are forecast to build to 8-12 ft, with the highest seas N of 29N. Another swell event will reach 30N140W on Tue. $$ GR