000 AXPZ20 KNHC 091002 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Thu Feb 9 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 0945 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Strong broad high pressure will build southwestward from the Gulf of Mexico Thursday night, and southwestward along eastern Mexico. This will create a tight pressure gradient along southern Mexico that will lead to the development of gale force winds starting late Thursday night through Friday night. Please see the latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFEP2/FZPN03 KNHC for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 04N88W to 01N99W. The intertropical convergence zone follows extending from 01N99W to 0N120W. Scattered moderate convection is in the vicinity of the surface trough from 0N to 05N between 88W and 104W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Strong northwest winds are ongoing over the central Gulf of California between a trough over the Gulf itself and high pressure over the central U.S. extending a ridge axis along central and eastern Mexico. Seas are likely reaching 7 ft in this area. Moderate northwest winds are observed off the coast of the Baja California peninsula north of Cabo San Lazaro and west of 115W, with seas to 6 ft. The pressure gradient will loosen today allowing winds to diminish across the region this afternoon. Light to moderate northwest to north winds are noted elsewhere and will prevail through the next several days. Long period northwest swell will propagate into the waters off Baja California Norte by Friday night through Sunday. Please see Special Features for information regarding the Gulf of Tehuantepec. The plume of seas to 9 ft with a component of northwest swell will reach 300 nm downstream to the west- southwest of the Gulf of Tehuantepec through Saturday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The pressure gradient between high pressure ridging extending southwest from the central Atlantic to the northern Caribbean Sea and lower pressures over the southwestern Caribbean Sea and Central America in combination with overnight drainage flow will support pulses of fresh to strong northeast winds through the Gulf of Papagayo during the nighttime hours through Sunday. Building high pressure north of the area Thursday will allow for a much stronger pulse and longer lasting of gap winds through the Gulf of Papagayo from Friday afternoon through Sunday. A plume of seas to 8 ft will reach roughly within 300 nm to the west and southwest of the Gulf of Papagayo with seas reaching a range of 8-10 ft by Friday night. In addition, strong northerly winds will move into the Gulf of Panama and off the Azuero peninsula Friday through Sunday morning with seas building to 8 to 10 ft. REMAINDER OF THE AREA... A cold front is moving into the northwest portion of the discussion area, currently reaching from 30N134W to 22N140W. Strong to near gale force southwest winds are N of 27N ahead of the front along with showers. Seas in this region are in the range of 8-13 ft in NW swell. Similar winds are W of the front N of 28N with higher seas reaching 17 ft. Upper support for the front will lift north of the area tonight, allowing the front to weaken as it moves eastward to 120W over the next 48 hours. Winds will diminish accordingly. Seas will subside as well, although wave heights to 12 ft in northwest swell will linger north of 25N and west of 130W through late Thursday. The remnant northwest swell in excess of 8 ft will propagate across most of the region north of 20N and west of 120W through late Friday, then decay to below 8 ft from west to east over most of this area though Sunday. $$ NR