000 AXPZ20 KNHC 270925 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 925 UTC Fri Jan 27 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... Eastern Pacific Gale Warning: A trough reaches from 16N133W to 1008 mb low pressure near 14N135W to 09N135W. The pressure gradient between this area of lower pressure and the subtropical ridge to the north of the area is supporting winds to gale force within 240 nm north of the low pressure, surrounded by a large area of strong to near gale force trade winds from 10N to 25N west of 125W. Seas are 12 to 16 ft in the area of strong winds due in part to longer period northwest swell propagating through the region. The gale force winds will diminish through Saturday as the low dissipates and the trough passes west of 140W. Gulf of California and Baja California peninsula Gale Warnings: 1040 mb high pressure is noted over the Great Basin, supporting strong to near gale force winds along the length of the Gulf of California this morning. Some of this momentum is crossing over relatively low points along the Baja California peninsula, with strong northwest winds pushing into Sebastian Vizcaino Bay and adjacent waters off Baja California. These winds will increase to gale force into Saturday as high pressure builds to the north, then will diminish through Sunday. Seas in the Gulf of California will increase to 8 to 13 ft, and similarly off Baja California peninsula along with a component of longer period northwest swell. 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 ITCZ axis extends from 03N90W to 02N100W to 1008 mb low pressure near 14N135W. Scattered moderate convection is noted from 11N to 20N between 125W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See special features section above for gale conditions along the Baja Peninsula and across the Gulf of California. Long period nw swell in the form of 6 to 9 ft seas are observed across the open waters north of 14N and west of 120W. These seas will be reinforced by another round of seas of 11 to 13 ft propagating southeast across the waters offshore to the north of 28N through Fri night. Mixing southwest and northwest swell resulting in seas of 4 to 7 ft are expected between 95W and 110W into Fri, then build from the north again on Fri night into Sat. Gulf of Tehuantepec: strong to near gale force northerly winds are expected in and downstream of the Gulf tonight with seas building to 10 ft near 15N95W early Friday. The north winds will diminish to a fresh breeze on Fri afternoon, then increase to a strong breeze again briefly late Friday night. A stronger gap wind event is forecast beginning on Saturday evening with gale conditions Sat night through sunrise on Tuesday. The strongest winds of 30 to 40 kt area expected on Monday evening with seas building to 18 ft near 14N96W. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Strong winds are forecast briefly around sunrise, then diminishing through midday. Stronger gap events are forecast tonight through Tuesday nights, with seas building to about 10 ft downstream of the Gulf waters near 10N88W on Tuesday. Gulf of Panama: Fresh n nocturnal 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... See special features section above for a gale warning near 15N135W. Otherwise, large northwest swell with combined seas to 12 ft currently across the discussion waters west of 110W will gradually subside. Strong southerly winds and large seas will spread e over the waters n of 22N w of 138W beginning on Sunday, ahead of a cold front reaching 32N140W late Tuesday. $$ Christensen