000 AXPZ20 KNHC 280751 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 751 UTC Sat Jan 28 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Gulf of California and Baja California Norte Gale Warnings: A strong 1048 mb high pressure is centered over the Great Basin north of the area. This is supporting gale force winds down the length of the Gulf of California. These winds well sampled in a scatterometer satellite pass from 04 UTC. The strength of these winds along with the duration and long fetch is allowing seas to build to as high as 13 ft in parts of the Gulf of California. In addition, gap winds to gale force are possible across portions of Baja California Norte, spilling over from the Gulf of California across the peninsula into adjacent Pacific waters. Most of this momentum extends across Sebastian Vizcaino Bay to the southeast of Punta Eugenia. Seas in this area are as high as 13 ft as well, with an added component of longer period northwest swell. The winds will diminish below gale force through tonight as the ridge weakens and shifts eastward. Eastern Pacific Gale Warning: An upper low centered near 12N140W continues to support a 1011 mb surface low near 10N140W with a trough extending to 15N135W. The gradient between this lower pressure and strong high pressure north of the region is supporting winds to gale force within 120 nm west of the trough. These winds will diminish below gale force later this morning as the low pressure weakens and shifts westward. Gulf of Tehuantepec Gale Warning: A strong gap wind event is forecast to begin on this evening with gale conditions quickly developing tonight, and continuing through sunrise on Tue. The strongest winds of 30 to 40 kt are expected on Sun afternoon and Sun night, with seas building to 19 ft near 14N96W. See the latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFEP2/FZPN03 KNHC for additional details on these warnings. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The intertropical convergence zone reaches form 03N90W to 02N105W to 09N125W to 08N135W. Scattered moderate convection is noted from 10N to 15N between 122W and 127W. Scattered moderate to strong convection is noted from 06N to 12N between 135W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See special features section above for gale conditions along the Baja Peninsula, throughout the Gulf of California and developing in and downstream of the Gulf of Tehuantepec. Strong winds are active near the mouth of the Gulf of California between Cabo Corrientes, Cabo San Lucas and farther to the south near Socorro Island. Seas in this area are reaching 8 to 10 ft in a combination of northerly wind waves and longer period northwest swell. Elsewhere long period northwest swell up to 8 to 12 ft are observed elsewhere across the open waters between 110W and 120W. These seas will gradually subside over the weekend. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to locally strong east-northeast gap winds will persist through this morning, then diminish. These winds will resume this evening, and then pulse to a strong breeze through Sun evening when the pressure gradient will tighten. Seas will build to about 10 ft downstream of the Gulf near 09N88W on Mon. The gradient will further tighten on Mon night, with near gale force ne winds and seas building to 11 ft. Gulf of Panama: Fresh to locally strong nocturnal north winds expected each night through the upcoming weekend. Light to gentle winds, and combined seas of 3 to 5 ft, are occurring elsewhere until swells from the gap events develop over the upcoming weekend. REMAINDER OF THE AREA... Aside from the area of gales mention in Special Features, a broad area of strong to near gale force winds is noted from 12N to 25N west of 120W. Seas are reaching as high as 12 to 17 ft in a mix of northeast wind waves and longer period northwest swell. Showers and thunderstorms persist from 07N to 13N between 120W and 140W. These winds will diminish quickly through tonight as the trough shifts westward and weakens. Seas of 8 to 11 ft will persist over much of the region primarily in northwest swell. Southerly flow will increase from 25N to 30N between 135W and 140W Sunday ahead of cold front approaching the region from the north central Pacific. The front will pass southeast of 30N140W early next week, reaching from 30N132W to 21N140W by early Tuesday. Strong to near gale westerly winds and 12 to 18 ft seas in northwest swell will follow the front. $$ Christensen