000 AXPZ20 KNHC 162220 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sat Feb 16 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 2000 UTC. ...SPECIAL FEATURES... POPOCATEPETL VOLCANO at 19.0N 98.6W is in a state of unrest. Volcanic ash from recent emissions has drifted westward to the Pacific coast during the past 24 hours and may be reaching the surface within 180 nm of the coast of Mexico between 102W and 105W. Mariners should exercise caution. If mariners encounter ash or floating volcanic debris, you are encouraged to report the observation to the National Weather Service by calling 305- 229-4425. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 05N77W to 05N86W to 04N93W. The ITCZ extends from 04N93W to 02N110W to 02N122W. A southern hemispheric ITCZ extends from 02S80W to 03S100W to 02S110W to 04S123W. Scattered moderate convection is noted from 02.5N to 06.5N between 87W and 100W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Strong high pressure anchored by strong high pressure NW of the forecast waters extends a ridge axis SE to just southeast of the Revillagigedo Islands near 15N111W. The pressure gradient between the ridge and lower pressure over the SW CONUS and Mexico continues to support fresh to strong NWly winds across the offshore waters of Baja California and southward to 19N. Seas across this area are running 8-10 ft in NW swell, while new large NW swell is entering the northern waters north of 28N to produce seas of 10-15 ft. Long period NW swell of 14-18 seconds will continue to spread SE across these offshore waters through Mon, with seas peaking at 10-16 ft across all waters N of 20N on Sun before gradually subsiding to 8-12 ft Mon. Strong winds are expected to increase to near gale force within 60 nm off the coast of Baja north of Cabo San Lazaro tonight as the ridge strengthens across the region, further tightening the presure gradient. The combination of these strong winds and large NW swell will produce very rough and dangerous marine conditions across the open waters through Mon, and produce very large and shifting waves along the coasts. Winds off Baja will diminish to around 15 kt on Tue with seas subsiding to 8-10 ft. Winds and seas will further subside through early Thu morning before strong low pressure moves into southern California during the day to bring strong to near gale force westerly winds into far N portions of the area. Weak troffing along and offshore of the coast near Manzanillo will maintain gentle and variable winds to the southeast of Cabo Corrientes through Mon, with offshore seas of 4-6 ft this afternoon prevailing through Sun then building to 5- 8 ft in new NW swell Sun night through Tue. Gulf of California: Fresh NWly winds prevail across the full length of the Gulf this afternoon and will strengthen to strong south of the Tiburon Basin this evening and tonight. Seas across southern portions will quickly build to 5-7 ft this afternoon and evening and reach near 8 ft tonight offshore of San Jose del Cabo. A weak cold front will enter the northern gulf waters on Sun night supporting fresh to strong SW to W winds N of 29N through Mon morning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate northeast winds in the Gulf of Papagayo will diminish tonight, but resume again Mon increasing to strong at night and continuing through Wed morning. Light and variable winds are expected elsewhere through Thu except for the Gulf of Panama where moderate northerly winds will dominate. REMAINDER OF THE AREA... A 1041 mb high centered well north of the Hawaiian Islands near 40N147W will persist across that region for the next several days, with an associated ridge extending SE and into the tropics near 12N107W through Mon. This pattern is currently producing a tight pressure gradient across the entire area N of 08N and W of 110W, resulting in fresh to strong anticyclonic wind flow W OF 118W. Recent scatterometer data showed strongest winds from 22N to 28N to the west of 135W, where E winds were a solid 25 kt, and seas estimated at 13-16 ft. New NW swell moving into the area has raised seas to 12-17 ft N of 25N while elsewhere seas are in the 8 to 12 foot range. This strong ridge will strengthen slightly during the weekend, and remain generally in place, and maintain this large area of strong NE to E winds across W and SW sections of the discussion area. Winds and seas will start to subside on Mon as a deep layered low pressure system affecting the Hawaiian islands for the past several days begins to move northward, which will nudge the strong ridge to the east and weaken it eastward of 120W across the local area. Otherwise, a weak cold front is forecast to enter the NE Pac waters by Thu morning. However, only seas to 11 ft in NW swell are expected at this time. $$ Stripling