000 AXPZ20 KNHC 031607 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 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 1200 UTC surface analysis and satellite imagery through 1545 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 Sat morning. .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 08N78W to 08N84W to 08N86W to 06N89W. The ITCZ extends from 06N90W to 05N103W to 07N111W to 08N121W then resumes near 05N131W and continues to 05N140W. Scattered to locally numerous moderate to strong convection is from 06N to 16N between 116W and 124W. Scattered moderate convection is elsewhere from 05N to 20N between 124W and 136W. ...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 islands. Fresh to locally strong N to NE winds prevail across the offshore waters of Baja California Sur through this afternoon with slowly subsiding seas of 5-7 ft in NW swell. Winds and seas will diminish very modestly through early Fri. A low pressure center currently embedded within the ITCZ will track N-NE and approach the offshores waters Sat night increasing the winds to moderate to fresh. Gulf of California: High pressure across the Great Basin region will support fresh to strong NW winds across the southern Gulf of California through tonight. Strong northerly winds will spill through the mountain gaps of the Baja Peninsula to produce narrow zones of strong 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 through early Fri morning. North winds will then 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 25N and W of 112W. 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 along about 135W overnight through Fri. This support a weak low pressure along the ITCZ between 120W and 135W. 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. This low pressure center and associated moisture will move northward through Fri and then weaken quickly as it veers northeastward, and affect Baja California Sur and the adjacent waters with fresh SW winds and occasional showers through the weekend. $$ NR