The first triple-digit day of summer season is forecast for the interior valleys in Mendocino and Lake Counties this weekend, according to a meteorologist with the National Weather Service.
James White, a meteorologist with the National Weather Service in Eureka, described the event as the "first kind of heat wave of the summer moving and building across the area here". He noted it will be "a pretty short one" but marks the first time many inland locations will reach 100 degrees Fahrenheit this summer.
The heat is expected to peak on Friday and continue through Saturday. Forecasts show "pretty high confidence" that temperatures will reach around 100 degrees Fahrenheit in the hottest valleys in Mendocino and Lake Counties.. Ukiah could see temperatures climb "just a couple degrees above 100".
Coastal areas, such as Fort Bragg, are expected to remain much cooler due to a "robust marine layer". High temperatures along the coast should only be in the 60s. Upper elevation locations in the northern part of the county and closer to the coast will also stay significantly cooler.
White explained that heat waves are typically very predictable because they are caused by "atmospheric ridges". These are "larger larger features" that are easier to forecast than other weather phenomena, effectively trapping hot air at the surface.
