Triple-Digit Heat Expected Across Inland Northwest California Through Early Next Week

The National Weather Services urges residents of inland areas of Humboldt, Del Norte, Trinity, Mendocino, and Lake counties to prepare for several days of unusually hot weather as temperatures climb well above seasonal averages, with some communities expected to see triple-digit highs through the weekend and into next week.

The National Weather Service office in Eureka has issued a Heat Advisory for Lake and Interior Mendocino counties today and Friday, warning that many valley locations could reach temperatures in the triple digits.

“Above normal temperatures are likely to continue into early next week,” the weather service said. (Note: Parts of Lake County are under a Red Flag warning which means weather conditions—including hot temperatures, low humidity, and strong winds—are creating a heightened risk that any new wildfire could start easily and spread rapidly.)

While coastal communities are expected to remain relatively mild, interior portions of the North Coast region will experience significantly hotter conditions. (Note: While coastal residents will be spared the triple-digit heat expected inland, temperatures along the coast are still forecast to run above seasonal averages, with some communities reaching the low- to mid-80s this weekend.)

In southeastern Interior Humboldt County, highs are forecast to range from 80 to 95 degrees today, increasing to as much as 100 degrees by Saturday. Temperatures are expected to remain in the mid-80s to upper 90s through at least Wednesday.

The hottest weather in Humboldt County is expected in northeastern Interior Humboldt, where temperatures could reach 102 degrees today, 106 degrees Friday, and as high as 111 degrees Saturday through Monday. Overnight lows are forecast to remain in the upper 50s and 60s, providing limited relief during the hottest period.

Interior Del Norte County is also expected to see a significant warming trend, with highs climbing from the upper 70s and low 90s today to between 85 and 100 degrees over the weekend and early next week.

Meanwhile, Northwestern and Central Trinity County are forecast to experience some of the hottest temperatures in the region. Highs are expected to reach 105 degrees today, 108 degrees Friday, and as much as 112 degrees Saturday through Monday. Temperatures are forecast to remain near or above 100 degrees through Wednesday.

Heat-related illnesses become more likely during extended periods of hot weather, especially for older adults, young children, outdoor workers, and people without access to air conditioning. Health officials recommend staying hydrated, limiting strenuous outdoor activity during the hottest parts of the day, wearing lightweight clothing, and checking on vulnerable neighbors and family members.

The National Weather Service is also reminding residents and visitors to be cautious around local rivers and waterways. Although air temperatures may be soaring, many North Coast rivers remain dangerously cold.

“Check water temperatures before your river visit,” the weather service advised. “Water temperatures below 70 degrees causes you to lose breathing and muscle control which can lead to drowning. The colder the water the more extreme the impacts.” (Note: Several local rivers stay below 70 degrees for much of the summer.)

Officials recommend wearing a life jacket, avoiding alcohol while swimming or boating, and being prepared for cold-water shock when entering rivers and streams.

Forecasters expect the hot and dry pattern to persist through at least the middle of next week.