000 AXPZ20 KNHC 162157 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Feb 16 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Gale Warning: Gale force northwesterly winds will develop late tonight into early Friday morning across the EPAC waters north of 27N and W of a cold front. The cold front is forecast to reach a position from 30N128W to 22N140W on Friday at 1200 UTC. At that time, minimal gale force southerly flow will develop within about 90 nm ahead of the front while NW winds in the 30-40 kt range and building seas up to 24-25 ft are expected behind the front, particularly north of 27N west of the front to 138W. The southerly gale conditions will shift E across the far offshore waters of PMZ009 and PMZ011 late Fri, then diminish to near gale force on Fri night. The northwesterly gale conditions will just briefly reach the far offshore waters of these two zones on Sat morning, then diminish to strong to near gale force flow that will shift E across the waters N of 20N through late Sun before diminishing to 20 kt or less. The associated large NW swell, in the form of 8 to 18 ft seas, will reach the entire coast of Baja Saturday through early Monday before subsiding. See statements from your local meteorological agency on this significant marine event for information on dangerous beach and surf conditions. Gulf of California Gale Warning: Gentle to moderate southerly flow will develop tonight across this gulf with increasing winds to 20-30 kt across the waters N of 30N on Friday. Then winds will further increase to minimal gale force on Fri night ahead of the major cold front described above that will move across the gulf waters on Sat and Sat night. Minimal gale force southerly winds are possible over the gulf waters S of 28N by late Sat. Refer to High Seas forecast under AWIPS/WMO headers MIAHSFEP2/ FZPN03 KNHC for additional details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The ITCZ and associated convection is located S of the area. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: See special features section above. Gulf of Tehuantepec: Strong northerly winds to 25 kt this morning with seas to 8 ft will continue to subside becoming variable less than 15 kt tonight and then southerly around 15 kt Fri and Fri night. Scatterometer data show gentle to moderate NW winds across the waters W of the Baja Peninsula with seas of 4-6 ft. Another round of NW swell will arrive late this afternoon and reach the coast of Baja to the N of 28N tonight, then spread SE across all waters N of 25N W of Baja Peninsula by Fri morning. The focus then turns to an approaching cold front with gale conditions expected to develop on both side of the front, and very large NW swell in excess of 15 ft through the weekend. Refer to Special Features section above. Light winds and 3 to 5 ft seas forecast elsewhere across the EPAC waters N of the Gulf of Tehuantepec through Fri. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Light to moderate winds today will become NE to E tonight and produce a brief pulse of fresh ENE winds across the region early Friday then gradually veer to E to ESE Friday night. Gulf of Panama: Moderate to fresh northerly flow is generally expected through Sat. Light to gentle winds, and combined seas of 3 to 6 ft, are occurring elsewhere outside of the swells originating near the gap events. REMAINDER OF THE AREA... A stationary front is over the NW corner of the forecast area and extends from 30N130W to 27N140W. Fresh to strong SW winds are within 60 nm SE of the front. Fresh to strong SW are also noted north of the front ahead of a second and stronger cold front forecast to enter enter the NW waters tonight. These fronts are expected to merge by Friday morning. Gale conditions are expected behind and ahead of the merging front. Please, see Special Features for details. A 1021 mb high pressure is center near 25N127W. This system will dissipate in about 24 hours as the aforementioned fronts move across the north waters. a couple of weak trough are also noted. One extends from 14N108W to 08N112W. Isolated moderate convection is within 150 nm on either side of the trough axis. the other trough extends from 05N89W to a 1012 MB low pressure located near 03N97W to 03N99W. Scattered moderate convection is near the trough axis. $$ GR