000 AXPZ20 KNHC 310335 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Mon Dec 31 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 0000 UTC surface analysis and satellite imagery through 0200 UTC. .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 10N74W TO 03.5N78.5W TO 04N91.5W. The ITCZ continues from 04N91.5W TO 05.5N125W to beyond 07N140W. Widely scattered to scattered moderate isolated strong convection is noted within 180 nm N and 90 nm S of the ITCZ W of 110W, and from 09N to 16N between 105W and 122W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A modest surface ridge extends from the NE Pacific to just SE of the Revillagigedo Islands late this evening, and is maintaining moderate NW to N winds across the offshore waters of Baja California, while fading northerly swell is maintaining seas in the 5-7 ft range. Another pulse of northerly swell will propagate into the waters off Baja California Norte tonight, building seas to near 10 ft on Mon. Seas will then subside through midweek. Gulf of California: A cold front will sweep southward across California and the Baja California Norte Tue through late Wed. Associated strong high pressure behind the front will build from the Great Basin of United States southward across the region by midweek, supporting strengthening NWly winds over the Gulf of California Tue through Thu. Strong winds across much of the Gulf by Tue night will spill through the mountain gaps of the Baja Peninsula to produce narrow zones of strong and gusty NE winds across the offshore Pacific waters of Baja California Tue night through late We night. Gulf of Tehuantepec: A strong gap wind event is expected late next week as a cold front sweeps across the western Gulf of Mexico. Northerly winds will strengthen across Tehuantepec on Tue, and possibly increase to gale force Fri. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE to E winds are expected across and downstream of the Gulf of Papagayo through Fri. Winds will peak to around 30 kt during the overnight and early morning hours with the assistance of nocturnal drainage flow. Frequent gusts to gale force are possible Mon night and Tue night within 120 nm of the coast. Moderate to fresh N winds are expected across the Gulf of Panama through Thu, pulsing to strong during the overnight hours. Elsewhere, gentle to moderate NE winds will prevail N of 08N, while gentle to moderate southerly winds are expected S of 08N. REMAINDER OF THE AREA... High pressure of 1031 mb centered N of the area near 37N134W extends a ridge SE across the forecast waters to just beyond the Revillagigedo Islands to near 19N108W. The pressure gradient between this area of high pressure and lower pressure in the vicinity of the ITCZ is supporting a broad area of fresh to strong tradewinds N of the ITCZ to near 23N and W of 113W. The area of high pressure will remain in place N of the area helping to maintain this broad area of fresh to strong trades. Long period NW swell is merging with this tradewind swell to produce seas of 8 to 13 ft over much of the area north of the ITCZ west of 120W. Global models continue to indicate a cold-core upper low will dig into the base of a mid/upper level trough early next week, supporting the development of a sharp surface trough or even weak low pressure along the ITCZ between 120W and 130W by mid week. This will likely enhance the trade winds north of the ITCZ and west of 120W, with near gale conditions possible over north portions of the surface trough or low. $$ Stripling