000 AXPZ20 KNHC 241556 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Jan 24 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... Gulf of Tehuantepec Gale Warning: A tight pressure gradient over southeastern Mexico behind a strong cold front, that stretches from the Yucatan Peninsula to northern Guatemala, has induced north to northeast gale force winds across the Gulf of Tehuantepec in the range of 30-40 kt along with seas in the 9-14 ft range. A the gradient slackens some, these winds will diminish to just below gale force this evening and continue to around 30 kt through late tonight. The gradient will tighten enough by daybreak Fri to allow for these winds to increase to minimal gale force, with seas of 9-14 ft. These winds will again diminish to just below gale force early on Sat, but seas will remain in the 9-14 ft range. A large area of seas, in the 8-10 ft range, will spread well to the south and southwest of the Gulf from tonight and Fri. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends southwestward from low pressure of 1008 mb over northwest Colombia to the coast of Colombia at 05N77W and continues to 03N83W to 05N95W, where it transitions to the ITCZ and continues to 04N105W to 06N113W and briefly pauses at 09N134W due to a surface trough that extends from 06N137W to 14N136W. The ITCZ resumes at 07N138W to beyond the area at 06N140W. Scattered moderate convection is within 120 nm north of the ITCZ between 105W and 111W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: Fresh to strong northwest winds are occurring from 23N to 29N along with seas of 6-8 ft in the central section of the Gulf. High pressure will strengthen over the Great Basin tonight and Fri further tightening the pressure gradient over northwestern Mexico and the Gulf of California areas. The winds will response by increasing in coverage, reaching to near 31N on Fri before diminishing in coverage late on Fri. These winds will then increase in coverage again on Sat as the gradient tightens. Seas with these winds will be in the range of 6-7 ft in the central Gulf of California on Sat. Elsewhere, high pressure to the north and northwest of the area is supporting moderate to fresh northerly winds west of the Baja California peninsula. Winds will diminish across this area Fri night and Sat morning as the high weakens and shifts north. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to strong northeast winds will continue across the Gulf of Papagayo through Sat. Peak seas yielded by these winds will be 8-9 ft. Gulf of Panama: Moderate to fresh north to northeast winds over the Gulf will occur mainly at night and into the early afternoon through Sat. REMAINDER OF THE AREA... Broad high pressure centered well north of the area extends a strong ridge across the forecast waters north of 10N. The pressure gradient between the ridge and a surface trough that extends from 06N137W to 14N136W is resulting in fresh to locally strong trades from about 12N to 18N and between 125W and 133W along with seas in the range of 9-11 ft. The Global models agree pretty much that the trough will lift north-northwest through the next couple of days, but differ on low pressure that is expected to develop from the trough. Presently, it appears that low pressure of around 1010 mb will develop by late Fri night near 15N and between 135W and 140W. The low could possibly deepen as it near 19N Fri night as it is expected to be situated to the southwest of high pressure ridging. The resultant gradient is forecast to bring strong northeast to east winds and peak seas of 10-14 ft from 15N to 23N between 125W and 138W by early on Sat. An extensive area of seas 8-11 ft in mixed northeast and northwest will cover the waters to the west of a line from 32N125W to 18N122W to 14N122W to 09N130W and to 03N140W by early on Sat. $$ Aguirre