Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
815 FXUS66 KEKA 092107 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 207 PM PDT Wed Sep 9 2026 .KEY MESSAGES... * Above normal interior temperatures likely through Thursday. * Chances for light rainfall for Del Norte and northern Humboldt Saturday. * Locally elevated fire danger Thursday, Friday, & Saturday afternoons in the interior. && .SYNOPSIS...Much warmer temperatures are likely today and Thursday, with warm temperatures even at the coast today. Cooler temperatures return to the coast Thursday and across the area Friday into the weekend. Light rain is possible for the northern half of the area. && .DISCUSSION...High pressure continues to bring much warmer than normal temperatures, both to the interior and the coast. Near or slightly above triple digit temperatures are likely for the interior valleys. This includes valleys close to the coast which may not have experienced temperatures this high so far this year, including Garberville and the Eel River valley. Overnight temperatures are low enough to provide enough cooling at night to lower the HeatRisk. This has also kept conditions below advisory criteria. Still, interior areas will see widespread Minor to Moderate HeatRisk which corresponds to a moderate risk for heat- related illness to those without proper cooling. Drink plenty of water and stay safe out there! Coastal areas also continue to warm as offshore flow continues to inhibit coastal stratus formation with mid to high 70s possible at the immediate coast and 80s possible just a few miles inland on Wednesday. Offshore flow weakens tonight into Thursday, which may support more coastal stratus to form or move onshore early Thursday morning. Stratus is likely to clear, at least partially, by the afternoon and relatively light sea breezes will still support a pleasant day in the mid to high 60s. Subtropical moisture from the remnants of Hurricane Marie have arrived today bringing high cloud cover over Mendocino & Lake this afternoon. Instability and moisture are both limited, so thunderstorm and shower chances are limited. However, the clouds are expected to limit the warmth this afternoon in the interior by a couple degrees. Troughing rebuilds Friday into the weekend, returning near normal temperatures and coastal stratus by Friday. By this weekend, much of the interior is forecast to be in the 70s and 80s with the coast in the low 60s. Light rain is becoming likelier for the northern portions of the area, with Del Norte having an 80% chance of any measurable rain, and northern Humboldt up to a 40% chance. Wetting rain (over 0.1") chances remain low at around 40% in Del Norte and 20 to 30% chances in northern Humboldt. /JB && .AVIATION...(18Z TAFs)...Offshore flow continues to inhibit coastal stratus formation. Offshore weakens somewhat tonight which may allow for stratus to form along the coastal areas, with the highest chances around sunrise on Thursday. Should stratus form, LIFR conditions are likely with the shallow marine layer. Any clouds that form are likely to lift shortly after sunrise, though most models do show stratus remaining just off the coast. /JB && .MARINE...Northerly winds and lingering steep seas continue to ease today. Breezy northerly winds return Thursday, particularly in the lee of Cape Mendocino. Near gale force gusts are possible by Thursday evening in the lee of Cape Mendocino and Cape Blanco. Winds ease Friday and Saturday as a weak front moves through the area. Strong northerlies return Sunday. Along with wind driven seas, a long period south swell from Hurricane Marie at around 2 to 3 ft continues through the waters. /JB && .FIRE WEATHER...Much warmer and drier conditions continue through Thursday. Afternoon relative humidity will be very low in the interior with most areas seeing single digits and teens. Tonight, offshore winds weaken somewhat which will support the redevelopment of a shallow marine layer and slightly improved relative humidity recoveries. Breezy onshore winds return Thursday afternoon and will elevate fire weather concerns as relative humidities remain low. The winds will be strongest, and the fire danger highest in Lake County and eastern Trinity County with these winds mainly in the afternoon and late evening. Locally critical conditions are possible. Troughing late this week into the weekend will return cooler temperatures and a deeper marine layer. Afternoon westerly to northwesterly winds will increase Friday and Saturday. The largest areas of concern will be the southern portions of the area, such as Lake County, that will remain dry. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory from noon Thursday to 3 PM PDT Friday for PZZ470. Small Craft Advisory from noon Thursday to 3 AM PDT Saturday for PZZ475. && $$ NOTE: The full forecast discussion is now regularly issued between 10 am/pm and 1 pm/am. Additional updates will be issued as needed. Visit us at https://www.weather.gov/eureka Follow us on Facebook and Twitter at: https://www.facebook.com/NWSEureka https://www.twitter.com/NWSEureka For forecast zone information see the forecast zone map online: https://www.weather.gov/images/eka/zonemap.png