Area Forecast Discussion
Issued by NWS Eureka, CA
Issued by NWS Eureka, CA
580 FXUS66 KEKA 160730 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 1230 AM PDT Sun Aug 16 2026 .KEY MESSAGES... * Smoke remains over areas outside of the marine layer due to local and distant wildfires. * Temperatures close to normal remains through the first half of the coming week. && .SYNOPSIS...An upper level troughing pattern has stalled over the eastern Pacific. Inland areas can expect cooler temperatures with the coast continuing to have overcast conditions and brief afternoon clearing. Generally mild weather is expected for the next week. && .DISCUSSION...An upper level trough has set up over the eastern pacific while an upper level ridge dominates over the central US. This pattern is forecasted to continue through the weekend and into early next week. The decreased surface pressure has supported a deeper marine layer with stratus reaching up the coastal river valleys with areas further inland experiencing seasonable temperatures in the upper 80s to lower 90s. Higher surface pressure may briefly rebuild early to mid week, but models are not showing a significant warm up and interior temperatures are likely to remain near normal (with most valleys in the 90s). Coastal areas are likely to see stratus persist through the afternoon, and this is likely to continue so long as afternoon winds remain light. Any clearing that does happen will most likely be short lived before filling in again after sundown. For the Trinity River Valley and areas in valleys of Trinity County, smoke will continue to form each day and settle in the valley floors each evening. Thankfully, weak inversions are likely to persist which should offer some slight relief from any dense smoke earlier in the day. && .AVIATION...With a deep marine layer has caused MVFR to IFR ceilings through the evening. Winds along the coast are light, yet should lean southerly through the overnight hours. Clearing in the morning is not expected, and if it occurs will be short lived. Inland areas will experience VFR conditions with winds switching between nighttime calm and daytime upvalley flow. Coastal river valleys are likely to see stratus (KUKI included) late overnight before clearing late in the morning. && .MARINE...Northerly winds remain in the outer waters with southerly winds in the inner waters where foggy conditions are likely. Short period waves will continue to decrease through Sunday before slowly growing again entering next week. A long-period southerly swell of ~3ft has built into the region as well. The overall sea state should remain mixed with these two wave groups through the start of next week. Light to moderately breezy (~20kt) winds are expected through the extended forecast of this coming work week. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... None. && $$ 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