000 AXPZ20 KNHC 122208 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sat Jan 12 2019 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... Gulf of Tehuantepec Gale Warning...High pressure building N of the region behind a cold front moving across the NW Gulf of Mexico today will support pulses of strong to near gale force winds through the Gulf of Tehuantepec starting tonight. Northerly winds are expected to begin to spread across the Gulf by around 0600 UTC and increase quickly to minimal gale force shortly before sunrise on Sun, then persist through Tue night or Wed. Strong gap winds will continue to pulse through the end of the week then gradually diminish as the high pressure weakens and shifts east of the Gulf. Seas will build as high as 15 ft in the area of gale force winds, with NE swell in excess of 8 ft propagating as far as 900 nm WSW downstream to mix with longer period NW and SW swell through early next week. For more information, see the East Pacific High Seas Forecast under WMO/AWIPS headers FZNT02 KNHC/HSFAT2. .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from the coast of Costa Rica near 010.5N83W TO 04.5N95W. The ITCZ continues from 04.5N95W TO 06N114W to beyond 04.5N140W. No significant showers or thunderstorms are associated with these features. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A cold front has begun to weaken as it moves into the far northern offshore waters and to near the coast of Baja California Norte, from 0N116W TO 27N117W TO 22.5N129W. The front will lose definition as it continues east across Baja California and the Gulf of California through Sun and become diffuse. Long period NW swell of 8 to 11 ft accompanying the front will move into the offshore waters of Baja California and the western Revillagigedo Islands through late Sun. The swell will largely subside below 8 ft from north to south through early Mon, just as another dissipating cold front approaching from the W delivers a new round of large NW swell. The reinforcing push of NW swell will cross most of the open offshore waters of Baja California and the Revillagigedo Islands to reach as far south as off the coast of Cabo Corrientes through mid week. Gulf of California: Light to gentle winds and slight seas will persist through the middle of next week, except for brief periods of southerly winds of 10 to 15 kt over the northern Gulf, influenced by the slow approach of weakening cold fronts tonight and again late Mon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Strong NE to E winds will prevail across the Gulf region. The strongest winds and greatest areal coverage downstream of the Gulf of Papagayo will be each night as nocturnal drainage flow augments the winds. Gulf of Panama: Moderate to fresh northerly winds will flow downstream to near 05N with accompanying seas of 5-7 ft will continue through the weekend. Winds in this area could become strong on Tue. The San Cristobal volcano in NW Nicaragua is no longer emitting volcanic ash this afternoon. REMAINDER OF THE AREA... A cold front extending from 30N116W TO 27N117W TO 22.5N129W will move east-southeast through Sun and gradually dissipate across central Baja California. Recent altimeter data and ship observations indicate seas of 10 to 15 ft in NW swell prevail in the wake of the front over the waters north of 20N. This swell is approaching an older area of seas exceeding 8 ft associated with a decaying area of NW swell lingering south of 17N. High pressure will build SE in the wake of the front and support development of an area of fresh to strong trade winds farther S from 07N to 12N west of 135W tonight through late Sun. Another cold front has entered the far NW portion of discussion area this afternoon from 30N137.5W TO 28N140W, and will cross the waters north of 25N through tonight. Strong winds are expected N of 27.5N in the vicinity of the front late today and tonight as the front passes between 140W and 130W. The current large NW swell N of 25N will subside to less than 12 ft by tonight. However, the new cold front will provide reinforcing swell of 12 to 15 ft across the waters north of 25N Sun and Mon. Looking ahead, yet another cold front will follow on the heels of the first two front and traverse the northern waters Mon through Wed and generate continued pulses of strong W winds and swell in excess of 12 ft. $$ Stripling