textproduct: Eureka

KEY MESSAGES

* Warmer temperatures with additional chances for light rain this weekend. * Stronger storm systems with heavy rain possible starting around or after November 10th.

* Minor to possibly near moderate coastal flooding is likely around Humboldt Bay from November 7th to 10th.

SYNOPSIS

Conditions will trend warmer and drier through the week and into the weekend. Another front will clip the area late Saturday into early Sunday, bringing chances for light rain for isolated areas. The weather pattern continues to look to trend more active mid to late next week.

DISCUSSION

A series of strong NE Pacific cyclones will form and impact regions north of CA in the Pacific Northwest and BC. These storm systems sent a weak front over far NW California Tuesday evening and another one is expected Saturday evening into Sunday. There is a higher chance of rain for the weekend system, with 30-50% chance for over a half inch of rain for N Humboldt to Del Norte. Though the much stronger winds will be farther north over Oregon, some recent model runs have trended the trough farther south, so the wind threat will need to be watched for the Del Norte area. Currently probabilities for gusts over 35 mph are low for the coast and ridges of Del Norte.

The NE Pacific troughs that pass well to the north will amplify ridging over the west. Temperatures will trend warmer in response. Ridging will peak Saturday when highs in some of the interior valleys are forecast to reach the upper 70s to 80 degrees, and this will be 10 to up to 20 degrees above average for the time of year.

The longer term forecast still holds a signal for a more active pattern, with ensembles showing the potential for more impactful storms capable of heavy rainfall and strong winds. Non linear error growth through the farther extended timeframe leads to over- amplification of the large Pacific storm systems in the global models. This is evident in the growing variability in solutions, with half the clusters depicting 1-2 inches of rainfall and the other 50% dry through the 11th through 12th of November timeframe with slightly better agreement later in the 12-13th. Strong southerly winds would also be probable with an atmospheric river type of weather system. JJW

AVIATION...(6Z TAFs)

A weak front is moving out of the area and skies are expected to mostly clear outside some of the interior river valleys. UKI is unlikely to see fog again early this morning, but still chances for lower ceilings or visibilities are around 15%. Chances of VFR conditions remaining at the coast through sunrise are over 60%, but some occasional MVFR ceilings are possible at CEC. Any clouds will lift and scatter by late morning. Winds generally remain light aside for northwest afternoon breezes of up to 10 to 15 kts. JB

MARINE

Northerly winds gradually build today peaking in the late afternoon and evening with 20 to 25 kt sustained winds south of Cape Mendocino and 10 to 15 kt winds north of the Cape. Steep seas are possible in the lee of Cape Mendocino with these winds. A mid period northwest swell of 8 to 10 ft arrives today which will keep seas elevated. Combined significant wave heights may reach up to 12 ft. Winds will ease Friday and into the weekend, but additional northwest swells will keep combined seas above 10 ft through at least Saturday.

Northerly winds are expected to weaken Friday and into the weekend as a weather system turns them southerly Saturday night into Sunday. The strength of these winds is still uncertain, but some moderate to near-gale force south winds are possible depending how far south this trough reaches. Behind this there is the potential for an even larger swell. The most recent model run is showing this building to around 13 to 15 feet at 15 seconds. However, previous model runs have shown this swell height as high as 17 ft. JB/MKK

COASTAL FLOODING

The positive tidal anomaly remains increased again, continuing bring tides higher than predicted. The increased southerly winds brought tides around 1.5 ft higher than forecast Wednesday at the North Spit gauge. Tides are officially forecast to reach 7.4 to 7.5 feet at North Spit on the 7th through 10th of November. The current range of tidal anomalies would bring tides up to and over the advisory level of 8.8 ft, and minor coastal flooding around Humboldt Bay. There will likely be periods of stronger southerly winds through those days, bringing higher confidence to at least minor coastal flooding, and perhaps near moderate.

EKA WATCHES/WARNINGS/ADVISORIES

CA... Beach Hazards Statement from this evening through Friday evening for CAZ101-103-104-109.

Frost Advisory until 9 AM PST this morning for CAZ106-110- 111-114-118.

NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory from 9 AM this morning to 3 AM PST Saturday for PZZ450-455.

Small Craft Advisory until 3 AM PST Saturday for PZZ470-475.