textproduct: Eureka

AVIATION 12Z UPDATE

Coastal stratus is creating IFR-MVFR conditions along the coast through the morning. Clearing is expected as northerly winds increase with gusts up to 30kts possible by the afternoon. A passing front is expected to keep skies mainly clear well into the evening with possible IFR returning to ACV late in the evening. Inland areas will see afternoon increases in terrain-driven winds and is expected to be VFR for the TAF period.

PREV DISCUSSION

/issued 359 AM PDT Sat Aug 29 2026/

KEY MESSAGES... * Breezy afternoon winds will elevate fire weather concerns in the interior this afternoon.

* Dry, generally mild, seasonable weather continues this weekend.

* Fall-like conditions possible next week with multiple chances of precipitation and cooler temperatures.

SYNOPSIS...Generally mild, seasonable weather continues across the area with slightly below normal interior temperatures and coastal areas seeing overnight stratus. A troughing pattern continues next week, brining below average temperatures and chances for precipitation.

DISCUSSION...Tropical moisture has moved out of the area as a trough moves into the Pacific Northwest. Winds increase on the backside of this trough and will bring breezy northwesterly to westerly winds this afternoon. The interior ridges and channeled terrain have a high chance from NBM of seeing gusts over 20 mph. There are more isolated but still sold chances for gusts over 25 mph, and locally up to 30 mph for the described locations. This will create some fire weather concerns in the interior, though the environment will be trending more moist in time.

The increased wind along the coast is likely to support the clearing of coastal stratus. Coastal areas are likely to continue to see high temperatures in the low to mid 60s, while near to slightly below normal temperatures continue in the interior areas. This pattern continues through the weekend and into Monday.

A cutoff low is modeled to form and sweep into Northern CA Tuesday. very little precipitation is forecast from this system. Models have been struggling will the latitudinal placement of this low along the California coast, but there may be instability with it. NBM is currently holding some 10-15 percent chance of thunderstorms Tuesday, but much could change with this if the low tracks farther south.

Confidence is growing on an additional colder, wetter system moving into the Pacific Northwest mid to late next week. The main uncertainty is how far south this will be positioned, but precipitation estimates continue to grow, with much of the North Coast at over 50% chances to receive at least a half inch of rain. Wetting rain (>0.1") chances are around 70% for the North Coast and around 20-40% for much of the interior outside Lake County. This is a ways out, so there is still plenty of time for this pattern to change, but right now signs are pointing to fall-like conditions. Regardless of precipitation, temperatures are likely to fall well below normal. Chilly morning lows in the 30s and 40s are possible for much of the interior. Stay tuned!

AVIATION...06Z UPDATE...Stratus has rebuilt over the coastal areas bringing MVFR ceilings. MVFR to IFR stratus impacts will continue overnight with occasional visibility reductions possible around sunrise with drizzle. Stratus is likely to lift and scatter shortly after sunrise returning VFR conditions. VFR conditions are likely to continue across the interior outside the near-coast river valleys for the next 24 hours. Breezy northwesterly winds gusts over 20 kts are possible at all terminals this afternoon and evening.

MARINE...Apart from areas around and south of Point St George, winds in the inner waters north of Cape Mendocino remain generally light. Otherwise, the northerly winds will strengthen across the waters through the weekend. Gust up to 35 kts can be expected around Cape Mendocino through the afternoons and evenings. An isolated area of gale strength gusts will expand farther into the southern outer waters this evening and into Sunday. Steep wind driven seas of 7 to 10 ft will develop as a result. These will combine with a long- period south swell arriving today. The northerlies will begin to quickly subside Monday as a troughing pattern returns. Seas and winds look to be quite low for much of next week from the troughing pattern. A stronger front with a round of increased southerly winds will be possible around mid next week, however.

FIRE WEATHER...A passing trough will increase northwesterly to westerly winds today, mainly through the afternoon hours. Gusts of 20 to 25 mph and locally up to 30 mph are likely for the interior ridges and channeled terrain. Relative humidity values will continue trending higher through next week with a continued troughing pattern, bringing some chances for rainfall and below normal daytime highs. NBM is bringing some slight chances (10-15 percent) of thunderstorms with the Tuesday system, but models are very inconstant with available instability and where the trough tracks in.

EKA WATCHES/WARNINGS/ADVISORIES

CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory from 9 PM this evening to 9 PM PDT Sunday for PZZ450.

Small Craft Advisory until 9 AM PDT Monday for PZZ455.

Small Craft Advisory from 3 PM this afternoon to 9 AM PDT Monday for PZZ470.

Small Craft Advisory until 3 PM PDT Monday for PZZ475.