000 AXPZ20 KNHC 050854 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 854 UTC Thu Mar 5 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Gales are expected to commence around midday Thu over the Gulf of Tehuantepec region as a strong cold front crossing the Gulf of Mexico ushers in strong high pres over the basin. Winds as high as 40 to 45 kt and seas topping out around 19 ft are expected as this event peaks Fri and Fri night. However, the gales and hazardous seas will persist through Sun night. High seas generated by these gales will combine with the area of 8 ft seas stemming from winds in the Papagayo region to cause an area of 8 to 10 ft seas to propagate downstream as far west as 120W by Mon evening. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 04N83W to 05N95W. The intertropical convergence zone continues from 05N95W to 07N120W, and again from 07N124W to 06N140W. Scattered moderate convection is present within 120 nm north of the ITCZ between 125W and 135W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A surface ridge extends southeast from 1022 mb high pressure near 29N125W to near the Revillagigedo Islands. The resulting relatively weak pressure pattern is maintaining gentle to moderate winds over all Mexican offshore waters. NW swell has diminished considerable off Baja California since yesterday, but a recent altimeter satellite pass showed linger 8 to 10 ft seas south of 20N and west of 105W, impacting mainly around Socorro Island. This should continue to diminish through early today. The surface high pressure will gradually shift east but maintain light to moderate NW to N winds over the waters west of Baja through Sat night. Strong SW winds will affect the Gulf of California north of 29N Sat night as a weakening cold front moves onshore from the Pacific. For more on the impending gale force gap winds over the Gulf of Tehuantepec, please refer to the Special Features Section. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: A strong ridge will remain in place over the Caribbean through the forecast period. Fresh to strong offshore winds across the Papagayo region will strengthen through the end of this week. Winds over the Gulf of Papagayo could reach near gale force Sun and Mon. Seas in this region could build as high as 11 ft during this time frame. Gulf of Panama: Moderate to fresh winds over the Gulf of Panama could become strong Sun, with seas building to between 8 and 9 ft. REMAINDER OF THE AREA... 1027 mb high pressure centered near 29N125W is supporting a broad area of moderate to fresh winds between 05N and 20N and west of 120W. Recent altimeter data shows seas are 8 to 12 ft in this area, likely with a component of northerly swell. Winds and seas in this region will diminish through tonight as the high shifts east and weakens. By Fri, a cold front will move into the waters north of 25N and west of 130W, bringing fresh to locally strong N winds and northerly swell of 8 to 9 ft. Looking ahead, this front is likely to dissipate for the start of next week as it crosses the Baja Peninsula and the Mexican State of Sonora. A relatively strong low pressure system for this time of year will approach 30N130W on Mon. Strong winds and seas building as high as 17 ft could affect the waters north of 20N and west of 130W as the attendant cold front swings SE into this area. For the waters E of 110W, gentle to moderate trade winds will prevail through the end of this week. Areas of 8 ft seas created by swell propagating downstream from likely gap winds over the Gulfs of Tehuantepec and Papagayo will expand and merge to encompass most of the waters south of 13N between 90W and 110W by late Sun. $$ Christensen