047 AXPZ20 KNHC 220323 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Mon Mar 22 2021 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. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from a 1008 mb low pressure located over northern Colombia near 10N74W to 08N85W to 02N99W. The ITCZ continues from 02N99W to 03N120W to 04N140W. Scattered moderate isolated strong convection is from 03N to 06N between 87W and 93W. Similar convection is also noted from 02N to 05N between 130W and 133W. As it is normal for this time of the year, a second ITCZ is analyzed south of the equator and extends from 04S90W to 01S98W to 03S110W to 01S120W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure of 1038 mb located near 36N140W dominates the offshore forecast waters of Baja California. The pressure gradient between this system and lower pressures over the SW CONUS is resulting in fresh to strong NW winds across the waters N of Cabo San Lazaro. As high pressure remains nearly stationary, the fresh to strong NW winds will spread southward reaching Cabo San Lucas by Mon morning. Seas of 8 to 11 ft in NW swell currently dominate most of the waters W of Baja California. This swell event will continue to propagate southward and beyond the Revillagigedo Islands by Mon morning. At this time, seas of 8 ft or greater will dominate most of the forecast waters N of 02N and W of 110W in a mix of NW and SW swell. Due a tight pressure gradient over NW Mexico, the Gulf of California and the Baja California peninsula, winds will briefly increase to 20 to 25 kt over parts of the Gulf of California tonight through Mon night. In addition, strong to gale force westerly winds are expected over northern Mexico and E of the Sierra Madre Occidental on Mon, with fresh to strong W to NW winds by Mon night. These winds blow between canyons over a higher terrain and then intensify. the mountain effect is amplified. A ridge across the eastern slopes of the Sierra Madre mountains in Mexico continue to support fresh to strong northerly winds across the Tehuantepec region, particularly N of 14N with seas to 9 ft. Winds will diminish to 20 kt or less across the Tehunatepec area by late Mon morning. Of note, the average date of the last Tehuantepec gale event is around April 9th. A couple of Tehuantepec gale events were detected in May base on the latest 20 years of records. Within this period, an average of 16 gale and 5 storm gap wind events is noted per cold season. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Fresh to strong winds are expected in the Gulf of Papagayo and downwind to about 90W through Mon night. Seas will build to 8-9 ft. Fresh N winds are expected in the Gulf of Panama at night through Mon night. Seas generated in the Tehuantepec region are now propagating across the offshore waters of Guatemala and El Salvador. This will diminish later tonight. Light to gentle winds will prevail elsewhere. Long period S to SW swell will maintain seas in the 4 to 6 ft range across the waters between Ecuador and the Galapagos Islands over the next several days. REMAINDER OF THE AREA... As previously mentioned, a strong high pressure system is N of the forecast area producing a tight pressure gradient across the northern forecast waters, particularly N of 18N W of 120W. The aerial extent of these winds will diminish on Mon, when the fresh to strong NE to E winds will dominate the waters from 12N to 28N W of 130W. By Tue, winds will increase again across the waters W of Baja California. Long period NW swell dominates most of the forecast waters W of 115W while long period cross equatorial SW swell continue to propagate across the area E of 115W, reaching the coastal waters of Mexico, Central America, Colombia and Ecuador. Additional pulses of SW swell will continue to invade the region during the next several days, $$ GR