000 AXPZ20 KNHC 020344 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Mar 02 2017 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 0315 UTC. ...Special Features... Gulf of Tehuantepec Gale Warning: A cold front over the northwest Gulf of Mexico will sweep across the remainder of the gulf through Thursday. Strong high pressure will build in behind the front, with northerly winds forecast to begin to funnel into the Gulf of Tehuantepec during the morning hours Thursday. The high pressure will surge southward along the Sierra Madre Oriental mountains over eastern Mexico during Thursday. This will help tighten the pressure gradient across the area and increase winds to gale force over the Gulf of Tehuantepec by Thursday night. Gale force winds are expected to continue over the Gulf of Tehuantepec through early Sunday before diminishing below gale force. Seas are expected to build to around 13 ft Thursday night, and reach near 16 ft on Friday. Please see the latest NWS high seas forecast under AWIPS/WMO headers MIAHSFEP2/FZPNO3 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... There is no ITCZ north of the equator. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see above for more on the next Gulf of Tehuantepec gale force gap wind event. Gentle to moderate northwest winds prevail over the waters off the west coast of the Baja California peninsula as well as the Gulf of California. Light to gentle winds prevail elsewhere. Seas are in the 5-7 ft range off the west coast of the Baja California peninsula, 2-3 ft over the Gulf of California, and 4-5 ft elsewhere. High pressure building over the Great Basin region of the United States will help increase winds over the Gulf of California today. Winds will reach 20 to 25 kt down the length of the Gulf of California through Thursday. The long fetch of northwest winds will allow seas to build to 8 ft from 24N to 26N by early Thursday. Light to gentle winds and 4 to 6 ft seas will prevail elsewhere over the offshore waters of Mexico through Saturday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo...Winds will pulse over the area through the rest of the week and the weekend. Winds will peak near 25 kt during the late night and early morning hours, and will diminish to 20 kt or less during the early evening hours. Seas with these winds will build to around 9 ft early each morning before subsiding below 8 ft early each evening through Saturday. Gulf of Panama...Winds will freshen each night before diminishing during the late afternoon hours through Saturday. Elsewhere, light to gentle breezes will persist through Sunday. REMAINDER OF THE AREA... Strong high pressure of 1034 mb located north of the area near 38N132W extends a ridge southeastward to near the Revillagigedo Islands. A tight pressure gradient between the high and lower pressure associated with the equatorial trough has resulted in a broad area of northeast to east trades mainly in the fresh range north of about 10N and west of 120W, except for a small swath of strong northeast to east winds from 21N to 22.5N between 128W and 136W. Seas within this area are generally 8-9 ft due to a mixture of northeast wind waves with northwest swell. The northwest swell will mix with a north to northeast swell through Friday. By Friday night, the north to northeast will be confined to west of 130W while long-period northwest swell is expected to be east of 130W into Saturday. The high pressure will begin to weaken Friday through Saturday as it shifts to the southwest. This should allow for the pressure gradient to slacken bringing a diminishing trend to the northeast to east trades. Seas in the 8 to 9 ft range will linger in the area of fresh trade winds between 05N and 20N, west of 125W into Saturday before subsiding through late Saturday. $$ Aguirre