textproduct: Eureka

KEY MESSAGES

* Very large surf tonight and into Saturday with breaking waves over 25 feet is possible. This will increase beach erosion and possibly bring some coastal flooding.

* Another cold front arriving late Saturday through early Sunday, brings another round of rain and strong southerly winds.

* A midweek storm is possible as the storm track remains set up over NW CA.

SYNOPSIS

A brief break in the rain expected Saturday before another system with more rain and winds arrives Saturday night and Sunday morning. Large and energetic swell arriving overnight into Saturday early morning hours. Likely to produce huge breaking waves.

DISCUSSION

A troughing pattern has set up over the Pacific Northwest, persisting through early next week. The first frontal boundary has passed with post frontal showers continuing and diminishing overnight into Saturday. The next frontal boundary with the next cutoff low will approach the area late Saturday and bring more southerly winds and moderate rain, but is expected to be weaker than the first.

Showers are expected to diminish overnight into Saturday for Humboldt, Del Norte and northern Mendocino counties. Generally dry weather is expected on Saturday, although there may be some localized lingering showers or drizzle for mountainous areas.

This calm period will be short-lived, however, as the next weather system moves in Saturday night into Sunday morning. This storm is forecast to be generally weaker than the storm today, yet rainfall amounts of a half inch in southeastern Lake County to nearly two inches in the mountains of Humboldt and Del Norte counties are possible along with gusty southerly winds. Around an inch to 1.5 inches are forecast for the rest of Northwest California. There is over a 70 percent chance for wind gusts greater than 40 mph along coastal headlands and exposed coastal areas of the Del Norte Coast (mostly just Crescent City and north) and southwest Humboldt (around the King Range). Otherwise, there is a high probability (greater than 80%) of wind gusts over 30 mph for the rest of Del Norte and Humboldt. The strongest winds will diminish by sunrise on Sunday with rain lingering through Sunday afternoon/evening.

Drier weather is possible Monday afternoon into Tuesday. Forecast ensembles continue to show a storm arriving mid week likely causing additional strong winds and rain for the area, yet details are limited and uncertain as of now. /JLW /EYS

AVIATION

Gusty south winds will fill back in by 16-17z at KCEC Saturday morning. KACV will follow suit a few hours later with gusty south winds starting around 20z. Post frontal calm expected overnight with VFR flight categories and light showers if any. Rain returns late Saturday night with the next rounds of fronts. Southerly winds at KUKI will be light and rain probabilities are low to moderate for Ukiah but possible by Saturday late evening.

MARINE

Seas remain elevated and defined by decaying southerly wind waves and a lingering mid period west swell of 10 to 12 feet. Late Friday evening/early morning Saturday, a very large NW swell of 27 to 30 ft at 18 seconds arrives which will develop into a very hazardous sea state. This swell peaks early Saturday and seas remain above 18 ft through Saturday evening.

Saturday night, a second cold front is forecasted to pass over the area once again creating strong gale to near storm force winds for the coastal waters into Sunday morning. Another large swell of 20 to 22 feet at 17 seconds arrives Sunday afternoon, keeping seas above 18 feet through Monday evening. Expect continued storms through next week as the storm track looks to remain fixed over our area through Wednesday at the earliest. JB/DS

BEACH HAZARDS

Just as strong winds and shower activity diminishes, a very large swell is expected to arrive to the shoreline. Global wave models shows this swell building to around 25-28 feet at 18 seconds. This could lead to breaking wave heights of up to 35ft. A High Surf Warning has been issued north and south of Cape Mendocino through 4am Sunday (11/15).

A second large swell at 19-22 feet at 17 seconds is forecast to arrive late Sunday into Monday. This will likely warrant a high surf advisory with breaking waves of around 25 feet.

High surf in northern California can be very dangerous. It is recommended to stay away from jetties, exposed rocks, steep beaches, and the waterline in general during these events. Large waves can rush up the beach knocking down individuals. Very large logs and tree stumps can also be carried by the waves adding to the hazards on the beach. Low lying parking lots next to beaches could see water inundation and bluffs may be subject to coastal erosion during the peak swell Friday night. Please remain safe and avoid beaches, jetties, and bluffs during periods of high surf.

COASTAL FLOODING

While the water levels inside Humboldt Bay continue to run 1.5 to 2.0 feet over the astronomical tides, the astronomical tides drop enough for coastal flooding to be non- existent or limited this weekend. However, the continued influence of the El Nino's abnormally warm water (Kelvin Wave), the persistent southerly winds and a large westerly ocean swell of over 25 feet will continue this weekend.

EKA WATCHES/WARNINGS/ADVISORIES

CA... High Surf Warning until 4 AM PST Sunday for CAZ101-103-104- 109.

NORTHWEST CALIFORNIA COASTAL WATERS... Hazardous Seas Warning until 3 PM PST Saturday for PZZ450.

Gale Warning from 3 PM Saturday to 3 AM PST Sunday for PZZ450.

Hazardous Seas Warning until 5 PM PST Saturday for PZZ455- 475.

Gale Warning from 5 PM Saturday to 3 AM PST Sunday for PZZ455-475.

Hazardous Seas Warning until noon PST Saturday for PZZ470.

Gale Warning from noon Saturday to 4 AM PST Sunday for PZZ470.