000 AXPZ20 KNHC 131513 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1513 UTC Thu Feb 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Strong winds behind a cold front in the western Gulf of Mexico will funnel through the Isthmus of Tehuantepec tonight, with gale force winds expected over the Gulf of Tehuantepec by late tonight. Gales are likely to persist through Sat night, with the strongest winds pulsing during the overnight and early morning hours in conjunction with nocturnal drainage flow. Seas are expected to build to 8-12 ft by Fri morning, and peak around 16 ft Fri night into early Sat. Refer to the latest High Seas Forecast FZPN03 KNHC/HSFEP2 issued by the National Hurricane Center, and the website https://www.nhc.noaa.gov/text/MIAHSFEP2 for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 05N77W to 04N87W. The ITCZ extends from 03N80W to 05N115W to 07N125W to 03N140W. No significant convection is noted. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on expected gale conditions in the Gulf of Tehuantepec. Weak ridging extends from 1034 mb high pressure well northwest of the area near 41N146W through the Revillagigedo Islands. The ridge has weakened through the morning as weak low pressure has moved into the waters off southern California. A recent ship observation indicate fresh northerly winds between Cabo San Lucas and Tres Marias Islands, but overall the fresh winds in this region are diminishing as the ridge weakens. Wave height in open waters are estimated to be 4 to 6 ft. A weakening cold front or trough may cross the northern waters Fri night into Sat. High pressure building behind the front will support fresh winds in the central Gulf of California Sat night through Sun night. NW swell will move across the Baja California offshore waters Sat through Sun, with seas expected to build to 8 ft off Baja California Norte, then decay by early next week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Strong to near gale force winds will prevail over the Papagayo region through Mon night, with a large area of fresh to strong winds expected well downstream of the Gulf of Papagayo each day. Swell generated by this gap wind event, combined with swell from the Tehuantepec region, will affect offshore waters of Guatemala and El Salvador through early next week. Highest combined seas of 8-11 ft are expected this weekend. Fresh to occasionally strong north winds will prevail over and downstream of the Gulf of Panama tonight early next week. REMAINDER OF THE AREA... High pressure over the waters north of 20N is supporting fresh to locally strong trade winds between the ITCZ and 20N west of 120W. Altimeter data indicates wave heights of 8-11 ft in this region, in mixed wind waves and residual NW swell. Little change is expected in marine conditions during the next two days. By this weekend, a mid-level low will cut off north of 20N west of 125W, which will induce the development of a trough farther south into the tropics near 125W. The gradient between this expected trough and high pressure over northern waters will result in strengthening trade winds and building seas, roughly between 120W and 130W later this weekend. $$ Christensen