000 AXPZ20 KNHC 151606 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Nov 15 2018 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 1545 UTC. ...SPECIAL FEATURE... Gulf of Tehuantepec Gale Warning: North to northeast storm winds from earlier have diminished this morning to strong gale force winds in the range of 30 to 45 kt, with maximum seas of 21 ft. These conditions are occurring within 60 nm either side of a line from 16N95W to 13N96W, including the Gulf of Tehuantepec. These strong gale force winds are forecast to continue to diminish through today reaching the range of 30 to 40 kt by late tonight into early Fri and to 30 to 35 kt by early on Sat as the culprit strong high pressure and associated tight pressure gradient weakens over eastern Mexico and the northwest Gulf of Mexico. Seas associated with the gale force winds will gradually subside to around 10 to 14 ft late Fri night and to 8 to 12 ft early on Sat, however, a large swath of 8 to 11 ft seas in mixed NE and SW swell will reach as far south as 04N and between 90W and 115W by then. ...TROPICAL WAVE... A tropical wave has its axis extending from 04N135W to 16N134W, moving westward at 10-15 kt. Scattered moderate convection is within 120 nm east of the wave axis from 08N to 11N. .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwestern Colombia to 09N79W to across southern Panama, and to 08N93W to 07N102W, where latest scatterometer winds indicate a transition to an ITCZ, which continues northwest to 08N115W to 09N133W and briefly ends near the tropical wave. It resumes at 08N136W and to beyond the area at 08N140W. Scattered moderate convection is seen within 120 nm north of the ITCZ between 129W and 133W, and also within 60 to 90 nm north of the ITCZ between 135W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to the Special Features section above for the ongoing Gulf of Tehuantepec gap wind event. Gulf of California: Fresh to strong north winds, with seas to 6 ft, are expected N of 30N through this afternoon. Moderate to fresh N winds and 1 to 3 ft seas are forecast across the entire gulf through tonight. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo...Strong northeast winds, with seas of 8 to 9 ft are expected through early on Sat. Northerly swell from a Gulf of Tehunatepec gap event will propagate into Guatemala and El Salvador offshore waters through Fri night. Moderate southwesterly monsoonal flow, with seas of 5 to 7 ft, is forecast S of the monsoon trough through the upcoming weekend. REMAINDER OF THE AREA... Refer to the Special Features section for swell propagating outward from the Gulf of Tehuantepec. A high pressure ridge extends into the area through 32N126W, and continues southeastward to just northwest of the Revillagigedo Islands. High pressure covers the area north of 20N and west of 110W. The pressure gradient between the high pressure and lower pressure over the sub-tropical region is allowing for fresh to locally strong trades along with seas in the 8 to 10 ft range to exist from 09N to 17N west of about 115W. As the high pressure weaken through Sat, this will slacken the gradient causing the trades to diminish to mainly moderate intensity. The high pressure will weaken as a cold front approaches the far northwest corner by early Sat. NW swell associated with the front will propagate through the waters west of a line from 30N138W to 27N140W, with seas up to around 9 ft. $$ Aguirre