AXPZ20 KNHC 160943

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Tue Jan 16 2018

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 0600 UTC surface analysis and satellite imagery through 0845 UTC.


Gulf of Tehuantepec Gale Warning: Gale force winds continue across the Gulf of Tehuantepec tonight, but are diminishing very slowly in strength and areal coverage from recent days. Peak seas downwind of the gulf are currently as high as 15 ft. Winds will continue to diminish slightly, though remain above gale force through Tue. A cold front will move into the Gulf of Mexico on Tue with associated high pressure building behind the front to tighten the pressure gradient over the area. This will again increase winds to strong gales across Tehuantepec Tue afternoon through Tue night. Winds are expected to finally diminish below gale force by Friday. The resultant plume of NE swell has propagated well southwest of Tehuantepec, with seas to 8 ft and higher currently reaching as far S as the Equator and as far W as 113W.


A surface trough extends from 09.5N74W to 05N77W TO 10N88.5W TO 05N92W. The ITCZ extends from 05N92W to 08.5N126W to beyond 08N140W. Scattered moderate to strong convection is noted from 02N to 08N E of 89W to coast of Colombia. Scattered moderate convection is noted from 04N to 08N between 91W and 102W. Scattered moderate isolated strong convection is noted within 90 nm N and 60 nm S of ITCZ between 94W and 118W. Scattered moderate to strong convection is noted from 07N to 12N between 118W and 136W.



W of the Baja California Peninsula: Large NW swell that generated very high surf of 30-40 ft across the Hawaiian Islands this past weekend is propagating into the area forecast waters tonight. Buoys offshore of southern California have recently shown wave periods in the 15 to 18 second range, with seas of 9 to 12 ft. This NW swell has reached the offshore waters of Baja California and will continue to build across the regional forecast waters through late Tue, peaking at 10 to 13 ft W of Baja California Tue afternoon through Tue night, and at 7 to 10 ft across the remaining offshore waters between Baja and Tehuantepec Tue night through late Wed. This large swell will generate very high and powerful surf along the coasts and outer reefs of Baja and mainland Mexico through Wed. Another surge of NW swell will reach the offshore waters off Baja California Norte Thursday night. Seas associated to this swell will peak near 16 ft by Friday. Seas 12 ft or greater will spread across the offshore waters off the entire length of the Baja Peninsula through the weekend.

Gulf of California: Light to moderate NW flow is forecast across across the entire gulf waters through Fri, except for a brief period of fresh winds Wed afternoon through Wed night.

See special feature section for information about the ongoing gale warning in the Gulf of Tehuantepec.


Fresh NE gap winds will continue to pulse to strong across and downwind of the Gulf of Papagayo the remainder of the week, with seas downwind building at or near 8 ft each early morning. Elsewhere N of 09N moderate gap winds will diminish to light to gentle by midweek, with mixed swell maintaining seas 4 to 7 ft before the strong NW swell arrives early Thu, raising seas to 5- 8 ft. S of 09N light to gentle winds will prevail.


Large, long period NW swell is propagating SE across the forecast waters tonight. Seas W of 120W have built to 10 to 16 ft, with highest seas still over the far northwestern waters. The swell will move SE across the discussion area while slowly subsiding through late Tuesday. By Tuesday, seas 8 ft or greater covering much of the forecast waters W of 107W, and then W of 100W by Wednesday. A next pulse of large NW swell will enter the NW waters Wednesday night, with seas peaking near 18 ft. This swell will build seas greater than 12 ft over much of the waters N of 15N and W of 120W by Sat night.

$$ Stripling