000 AXPZ20 KNHC 171605 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1405 UTC Sun Dec 17 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 1200 UTC surface analysis and satellite imagery through 1430 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The ITCZ extends from 05.5N96W to 10N123W to 10N140W. There is no significant convection currently associated with the ITCZ. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: A deep layered low pressure system is crossing the northern Gulf of California and is currently centered near the Arizona/Sonora border just SW of Tucson. This system was reflected by a 1004 mb low centered at the surface near 31N113W at 12 UTC. A cold front extends SSW across the Gulf of California and Baja California Norte to 28N114W then continues SW to 24N117W. The low has been intense enough to produce a line of thunderstorms earlier this morning along and ahead of the front north of 27N. The convection has since moved eastward into Arizona and NW Sonora. The front has begun to weaken and will continue moving SE and finally dissipate over the S central Gulf by Mon morning. S to SW winds have developed over the northern and central Gulf ahead of the front to 111W. Strong NW winds will affect the Gulf north of 30N as the surface low lifts NE toward Arizona and weakens. While the fetch across the northern Gulf will be too limited to develop large seas, mariners should consider the possibility of strong gusty winds funneling through low lying areas of Baja California Norte today. Winds in this area will diminish through early next week after the low fills and the front dissipates. Across the Pacific offshore waters, NW winds have strengthened behind the front to 20-25 kt, and seas have built to around 16 ft near 30N122W. Seas are peaking and will start to subside, but Seas of 8 to 10 ft will cover most of the waters beyond 60 nm of the Baja coast through Mon afternoon. Elsewhere, gentle to moderate winds and 3 to 5 ft seas will persist along the coast of Mexico outside of the Gulf of Tehuantepec through mid week. Gulf of Tehuantepec: Strong winds over the Gulf of Tehuantepec have subsided for the time being, but nocturnal drainage winds will pulse to strong speeds each night through Thu morning. A strong cold front blasting into the Gulf of Mexico should usher in the next gap wind event beginning on Sat night. Gale force winds will be possible. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Strong gap winds are expected to continue across the Papagayo region for the the next few days, but gradually taper off as high pressure over the western Atlc shifts eastward. Fresh N winds will funnel across the Gulf of Panama tonight, then decrease to moderate speeds Mon night. REMAINDER OF THE AREA... Fresh to strong winds prevail over the waters N of 24N, with seas 9 to 16 ft in NW to N swell. Seas associated with this swell are peaking and will start to subside this afternoon. Moderate to fresh trade winds prevail elsewhere over the forecast waters north of the ITCZ to 20N and west of 125W. High pressure across the NE Pacific will dominate the regional waters for the next few days with little change wind speeds. Seas across much of the region west of 110W will subside below 8 ft during the next couple of days as long period NW swell continue to decay. Low pressure developing west of 30N140W will cause seas near the NW corner of the discussion area to build above 8 ft by Fri morning. $$ CAM