000 AXPZ20 KNHC 032211 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 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 1800 UTC surface analysis and satellite imagery through 2145 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 early Fri, increasing to gale force Fri late in the afternoon through Sat morning. Please see the National Hurricane Center High Seas Forecast under WMO/AWIPS headers FZPN03 KNHC/HSFEP2 for further details. A large area of disturbed weather associated with a broad area of low pressure is centered near 11N124W. The low is forecast to move slowly northward over the next few days and could acquire some tropical or subtropical characteristics during that time. Regardless of tropical or subtropical cyclone development, the low is expected to produce gale-force winds Fri afternoon through Sat evening. There is a low chance for this system to become a tropical cyclone within the next two days. Please see the National Hurricane Center Tropical Weather Outlook under WMO/AWIPS headers ABPZ20 KNHC/TWOEP for further details. .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 just NW of Las Tres Marias islands. Moderate to fresh N to NE winds are across the offshore waters of Baja California with seas of 5-7 ft in NW swell. Winds and seas will continue to diminish through Fri morning. A low pressure center currently just N of the ITCZ will track N-NE over the weekend, approaching the offshores waters early Sun. NW swell associated with a weakening cold front and mixed swell associated with the low will start affecting the Baja offshore waters by Sat night while winds are forecast to increase to fresh during Sun afternoon. Gulf of California: High pressure across the Great Basin region will support fresh to strong NW winds across the Gulf of California S of 29N through tonight. 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 late in the afternoon, as discussed in the special features. 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 early next week. Fresh winds are expected elsewhere from El Salvador to Panama through Fri. Moderate to fresh N winds will prevail across the Gulf of Panama through tonight. 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 23N and W of 117W. 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 11 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 supports a weak low pressure just N of the ITCZ. The resultant tightened pressure gradient will enhance trade winds north of the ITCZ and west of 120W. The 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. Gale force winds are expected with this low. See special features for further details. $$ NR