000 AXPZ20 KNHC 030355 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Jan 3 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...SPECIAL FEATURES... ...Gale Warning... A cold front is expected to move across the western Gulf of Mexico Thu and reach the Bay of Campeche early Fri. Winds behind the front will funnel into the Gulf of Tehuantepec Fri morning, increasing to gale force Fri afternoon through and Sat morning. .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 09.5N74.5W TO 03N79.5W TO 05N85W. The ITCZ extends from 05N85W TO 06N88.5W TO 07N128W to beyond 06N140W. Scattered to locally numerous moderate to strong convection was noted from 04.5N to 11.5N between 106W and 138W. Scattered moderate convection was noted from 11.5N to 19N between 104W and 138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure centered to the NW of the area extends a ridge SE to near Las Tres Marias. A cold front has dissipated this afternoon across the area from NW Mexico across Baja California Sur to near 26N128W. Fresh to locally strong N to NE winds prevail across the offshore waters of Baja California this evening with slowly subsiding seas of 5-8 ft in NW swell. Winds and seas will diminish very modestly through early Fri. Gulf of California: High pressure across the Great Basin region will support fresh to strong NW winds across the full length of the Gulf of California through Thu morning. Strong northerly winds 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. Gulf of Tehuantepec: Fresh northerly gap winds will prevail across the near shore waters of the Gulf tonight through Thu morning before becoming light and variable Thu afternoon. North winds will then return Thu night and increase to 20-30 kt by Fri morning as a cold front approaches the region from the north. Gales are expected to commence by Fri afternoon, as discussed above. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Strong NE to E winds are expected across and downstream of the Gulf of Papagayo through Fri. Fresh to strong offshore winds are expected elsewhere from El Salvador to Panama through Fri. Moderate to fresh N winds will prevail across the Gulf of Panama through Thu, pulsing to strong during the overnight hours. Elsewhere, gentle to moderate southerly winds are expected S of 08N. REMAINDER OF THE AREA... The pressure gradient between high pressure N of the area and lower pressure in the vicinity of the ITCZ is maintaining a broad area of fresh to strong tradewinds N of the ITCZ to near 24N and W of 115W. This 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 12 ft over much of the area north of the ITCZ west of 120W. A cold-core upper low will continue digging southward into the base of a mid/upper level trough between 130W and 145W this evening through Fri. This will support the development of a sharp surface trough and eventually weak low pressure along the ITCZ between 120W and 135W on Thu. The resultant tightened pressure gradient will enhance trade winds north of the ITCZ and west of 120W, with near gale conditions possible developing north of the surface trough and low to near 16N. Active convection will prevail north of the ITCZ across this area today through Thu night. $$ Stripling