Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
438 FXUS66 KEKA 122159 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 159 PM PST Fri Dec 12 2025 .SYNOPSIS...Dry, calm, and foggy weather will persist through the weekend. Wetter weather will finally return next week with period of light to moderate rain and wind focused along the North Coast early in the week. && .DISCUSSION...High pressure and offshore flow are expected to bring very persistent conditions through the weekend. Valley fog is expected each night in some of the valleys, mainly in the same ones that saw fog this morning. Local areas of dense fog are expected. This may be on the valley floors or a few hundred feet above on the hills. High temperatures in the northern valleys will remain cool and in the upper 40s to upper 50s. A pattern change with a return to wetter weather is expected to start next week. Initially this will mainly be in the north, but will expand south through the week. It generally looks like there will be systems on Monday and Tuesday. Wednesday there is expected to be a short break with another system Thursday or Friday. There is some discrepancies in the models on the start of the rain on Monday. The NBM starts to bring rain to Humboldt and Del Norte county by mid morning, but some the deterministic models show it holding off until some point in the afternoon. There are also southerly winds with this so for the Humboldt Bay and Eel River Delta, expect it will start on the later end of the range due to the downsloping. Farther south and east in Trinity, Mendocino and especially Lake counties will remain dry through most of the daylight hours. The ensembles are still showing some differences in how far south the heaviest rainfall will make it. Monday and Monday night rainfall amounts are expected to range from 1 to 2 inches in northern Humboldt and Del Norte counties, 02.5 to 0.75 in southern Humboldt and Trinity counties. Northwestern Mendocino county may be near a half inch, with most other areas being less than a quarter inch. Winds with this first system are expected to gust to 30 to 40 mph on the higher terrain. Tuesday and Tuesday night the next round is expected with rainfall amounts currently forecasted to range from 1.5 to 3 inches north of Willits. Areas farther south are only expected to a see 0.5 to 1 inch. Winds are expected to be stronger with this second system. The GFS is briefly showing gusts to 50 kt at 850 MB over coastal Humboldt and Del Norte counties. This will likely bring gusts to of 50 to 60 mph to the ridges in this area, but this may not mix down to the surface. Areas farther south and east will be lighter. Wednesday it looks like there may be a brief lull in the rain. Pops remain fairly high, but amounts generally look to be less than a tenth of an inch through the day. Thursday the ensembles are in good agreement on another weather system bringing more rain to the area. This system may be slightly colder, but snow levels are still expected to be over 5,000 feet. MKK && .AVIATION...(18z TAFs)...Variable conditions at KACV this afternoon as a dip in visibility brought VFR conditions down to IFR (1 1/4 statute miles) with haze and mist. A tempo lasting until 23z should signal the threat/possibility of the occurrence. KCEC has faired better this afternoon with VFR and northerlies just under 10kts or so. Winds will shift easterly by 03-04z at KCEC and eventually prevail from the south as a shortwave moves through the area Saturday morning. Similar conditions for KACV are to be expected, along with lifted ceilings via deepening marine layer. KUKI will have prevailing VFR conditions. Rain is likely Monday into Tuesday for most of the terminals in the CWA. /EYS && .MARINE...Northerly winds have been light in most of the area waters this afternoon. A few buoy reports near Pt. St. George reporting gusts 10-12kts but overall conditions will improve as the fetch area moves away from shore tonight in lieu of an approaching frontal boundary. Southerly will be the prevailing direction into the middle of next week with gusts building Monday afternoon to 30-33kts. A westerly swell around 5-7ft at 12-13 seconds will start to decay Sunday. Northerly wind waves will diminish tonight as it gets displaced by the approaching shortwave and its boundary winds. /EYS && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 3 AM PST Saturday for PZZ470. Small Craft Advisory until 3 PM PST this afternoon 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