textproduct: Eureka

KEY MESSAGES

* Warmer temperatures with a couple slight chances for light rain or drizzle this afternoon and evening and again 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. A couple fronts will clip the region this evening and 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 will send a couple weak, clipping fronts today and Saturday/Sunday. The front today will likely on bring trace amounts from a few showers or light drizzle, mainly to Del Norte County. There is a higher chance of rain for the weekend system, with 40-50% chance for over 0.3 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 element 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

A weak front is bringing some mid level clouds to much of the area this afternoon as a weak front approaches. Near Crescent there may be a few showers, but otherwise VFR conditions are expected in most areas. Later tonight some low clouds may develop along the Humboldt coast and could impact KACV. There is some offshore flow making confidence low on this. In many of the inland valleys fog is expected to develop again tonight. At this point it looks like it will remain north of Ukiah, but have hinted at it in the KUKI TAF. Thursday any clouds are expected to clear out by mid to late morning and VFR conditions are expected in the afternoon. North to northwest winds are expected, but will likely remain under 10 to 15 kt. MKK

MARINE

A weak front is bringing some local southerly winds south to the Del Norte coast. These may briefly go farther south. The west to northwest swell is slowly diminishing and is around 8 to 9 feet at 12 seconds. This is expected to continue to diminish tonight. Late tonight and Thursday the northerly winds are expected to return and increase across the waters. Around the same time a northwest swell is expected to build to around 5 to 8 feet at 15 seconds Thursday morning and continue to build into the evening to around 9 to 11 feet at 11 seconds.

Northerly winds are expected to weaken Friday and into the weekend as a weather system turns them southerly Saturday night into Sunday. Behind this there is the potential for a very large swell. The most recent model run is showing this building to around 15 to 20 feet at 16 seconds. This will likely change multiple times again, but is worth monitoring. There is also the potential for the strong low to move slightly farther south and bring some stronger winds. MKK

BEACH HAZARDS

An eastward propagating, strong Aleutian low will deliver a second long period WNW swell. The swell will arrive late Thursday with periods up to 20 seconds. The swell will peak at around 11 to 13 ft at 17 seconds Friday, bringing a low to moderate risk for sneaker waves.

Sneaker waves are a unique hazard, with up to 30 minutes between waves. Large, unexpected waves can sweep across the beach without warning, sweeping people into the sea from rocks, jetties, and beaches. These sneaker waves can also move large objects such as logs, crushing anyone caught underneath. Even ankle to knee deep water can knock you down and drag you out when a sneaker wave hits. Pay attention and stay above the high water line and any wet sand to stay safe. If the ground is wet, waves have surged there recently. Stay safe and never turn your back on the ocean!

COASTAL FLOODING

The positive tidal anomaly remains increased again, continuing bring tides higher than predicted. The increased southerly winds brought tides 1.8 higher than forecast Tuesday at the North Spit gauge, but the anomaly is currently at 1.4 ft. 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... Frost Advisory from 11 PM this evening to 9 AM PST Thursday for CAZ106-110-111-114-118.

NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory from noon Thursday to 3 AM PST Friday for PZZ450-455.

Small Craft Advisory from 9 AM Thursday to 3 AM PST Friday for PZZ470.

Small Craft Advisory from 3 AM Thursday to 3 AM PST Friday for PZZ475.