000 AXPZ20 KNHC 061557 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1326 UTC Sun Jan 6 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 1500 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Winds are forecast to increase again to gale force across the Tehunatepec region Tue morning through Thu night. Currently, marine guidance suggests winds of 30 to 40 kt and seas building to 14 or 15 ft Wed and Wed night. This gap wind event will be associated with a cold front moving across the Gulf of Mexico followed by a strong high pressure system. Please see the latest High seas Forecast product under AWIPS/WMO headers HSFEP2/FZPN03 KNHC for more details. .INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from a 1009 mb low pressure located in Colombia near 08N74W to 05N81W to 06N87W to 05N90W. The ITCZ continues from 05N90W to 08N112W to 05N130W beyond 04N140W. Scattered moderate isolated strong convection is within about 75 nm S of the ITCZ axis between 105W and 110W. Similar convection is also noted near 10N114W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weakening cold front is moving across the offshore waters of northern Baja California followed by a set of long period NW swell. Seas of 8 to 12 ft will propagate across the waters W of Baja California today, with seas then subsiding to 8 to 10 ft by tonight. The front will continue to weaken as it approaches the coast of Baja California, where it is forecast to dissipate tonight. In addition, a surface trough extending from 23N115W to 18N118W to 15N122W is bringing fresh to strong N-NE winds and seas of 8 to 10 ft to the offshore waters W of Baja California Sur. Winds and seas will diminish late today. Gulf of California: Light and variable winds are expected through tonight. On Mon, expect NW winds of 15 to 20 kt mainly S of 27N as the pressure gradient tightens over north-central Mexico. By Tue, moderate to fresh NW winds will affect most of the Gulf of California waters. Winds will become light and variable again over the northern Gulf by Tue night. However, moderate to fresh NW winds are forecast to persist across the central and southern Gulf through Thu. Gulf of Tehuantepec: Please, see Special Features section for details. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to strong NE to E winds are expected across and downstream of the Gulf of Papagayo through Thu. Winds will be greatest during the overnight and early morning hours with the assistance of the nocturnal drainage flow, and some added enhancement from the easterly gradient flow from the SW Caribbean. Gulf of Panama: Expect fresh to locally strong northerly winds and seas to 8 ft through early Mon morning, particularly N of 05N between 79W and 81W, including the waters near the Azuero peninsula. Winds are expected to increase again by Thu night. REMAINDER OF THE AREA... A surface trough extends from 23N115W to 18N118W to 15N122W. A weak 1013 mb low pressure is along the trough axis near 18N118W. The pressure gradient between the trough and a 1024 mb high pressure situated near 27N144W is resulting in an area of fresh to strong N-NE winds within about 60 to 90 nm on the west side of the trough axis with seas of 9 to 10 ft. These marine conditions will persist through Mon morning as the trough drifts eastward and dissipates. A relatively small area of fresh to strong trade winds is also noted due to the pressure gradient between the aforementioned high pressure and lower pressure in the vicinity of the ITCZ. This area of trade winds covers mainly the waters from 11N to 17N W of 135W. A strong cold front is forecast to reach the NW corner of the forecast area by early Mon afternoon. Strong to near gale force winds are expected on either side of the front. A new set of long period NW swell will follow the front. Seas are forecast to build to 20-22 ft behind the front and near 30N140W by Mon night. $$ GR