textproduct: Eureka

SYNOPSIS

Dry weather and above normal daytime temperatures will continue through much of the upcoming week. Overnight and morning temperatures will remain chilly with patchy dense fog along the river valleys and around Humboldt Bay.

DISCUSSION

Resilient high pressure continues to dominate the region, leading to dry weather and above-normal temperatures. A shallow marine layer up to 2,000 feet is forming this evening, with low clouds lapping the coastal areas today (1/20/26). Low temperatures are forecast to remain chilly with areas of fog and patchy dense fog along the shelter valleys. If you are interested in catching a glimpse of the aurora late tonight, your location matters! Low coastal stratus clouds will likely hinder viewing for those along the coast tonight. Meanwhile, clear to partly cloudy are expected for the interior areas, offering a much better opportunity until around 2AM tonight.

The 500 mb blocking flow pattern will continue the persistent dry weather for NW California through the end of the week. A shortwave trough will undercut the block on Wednesday, resulting in a deeper marine layer with some low clouds pushing into the interior river valleys. Ensemble guidances shows the ridge rebuilding Thursday and Friday, with offshore flow strengthening. This dry offshore flow will most likely reinforce the chilly overnight low temperatures.

Beyond Friday, global models are now trending drier across the region. NBM probability for light rain or drizzle (0.01 inch or more) has increased to around 40% for Del Norte and northern Humboldt on Sunday night. Probabilities for 0.1 inch or more around 30%. That said, generally dry conditions and above normal daytime temperatures are expected to continue through the next 7 days. /ZVS

AVIATION

The marine layer remains in place along much of the coast. Around ACV the clouds are firmly in place and it is likely it will remain LIFR early this morning. It may drop below 1/4 mile at times, especially towards morning. KCEC is a bit more patchy with the clouds. It will likely continue to see periods of LIFR conditions, but there may be some breaks in the clouds at times. This morning clouds are expected to lift slightly in the morning and may break out to VFR in the afternoon. However this will likely be shortlived with the HREF showing a quick return of lower cigs and vis in the evening along the coast. Inland areas are expected to see low clouds and fog return to many of the northern valleys, likely in the areas where there was fog on Sunday. UKI is expected to remain VFR. MKK

MARINE

Northerly winds have diminished to 5 to 15 and these will continue to diminish today (Tuesday). The wind driven waves are also diminishing. A long period wave is starting to building into the waters and is expected to build to around 5 to 6 feet at 16 seconds by late this afternoon. This is expected to combine with a 3 or 4 foot wave of 12 seconds.

Lighter winds are expected Tuesday and Wednesday. Wednesday night and into Thursday northerly winds are expected to strengthen again. These are expected with near gale to gale force gusts winds are expected to develop. These are expected to peak on Friday or Friday night before diminishing for the weekend Sunday into early next week southerly winds are expected to return. MKK

BEACH HAZARDS

A moderate increase in the risk for sneaker wave will early this morning. A Beach Hazard Statement, has been issued for Northwest California coastline due to a westerly swell 4- 6ft with a period around 16-17 seconds. The earliest estimated arrival is early this morning (1/20/26) for Coastal Del Norte, Northern Humboldt Coast, and Southwestern Humboldt ending around 8 P.M. tonight. The increased sneaker wave threat is expected for the Mendocino county beach zones beginning at 7 AM this morning (1/20/26) and ending at 8PM tonight.

EKA WATCHES/WARNINGS/ADVISORIES

CA... Beach Hazards Statement from 4 AM PST early this morning through this evening for CAZ101-103-104.

Beach Hazards Statement from 7 AM PST this morning through this evening for CAZ109.

NORTHWEST CALIFORNIA COASTAL WATERS... None.