Wildfire Outbreak in Northern California

Northern California is ablaze with wildfires.

As of Thursday, according to CalFire, 22 wildfires are burning in the Golden State. They have scorched over 190,000 acres and forced the evacuation of entire neighborhoods. Officials say at least 26 people have been killed and more than 400 are missing. In terms of property damage, they conservatively estimate that 3,500 homes and structures have been destroyed.

The smoke and ash from these fires are also causing widespread air quality issues. In the Bay Area, well outside of the burn zone, air quality reached historically poor levels this week.

These huge fires are largely the result of climate whiplash. California has distinct wet and dry seasons, but they have been extreme recently. After years of drought, this winter brought the state record amounts of precipitation that spurred explosive new plant growth. Then during the summer, which was the state’s warmest on record and unusually dry, all that vegetation turned to tinder.

Making matters worse, the region’s seasonal winds known as the Diablo Winds began blowing over the weekend. They reportedly reached speeds as high as 70mph in some areas. Blowing east to west, these winds warm from compression as they flow downslope from the mountains towards the coast and dry out vegetation even further. They also fan the flames of any fire already burning and can cause it to spread very quickly.

The Diablo Winds are essentially the same type of air current as the famous Santa Ana winds in southern California. They only really differ in location and name. The Diablo Winds are named for Mount Diablo in the East Bay area and the Santa Ana Winds are the namesake of Santa Ana Canyon in Orange County.

Wildfires are not unusual in California, but this outbreak is considered one of the worst in state history. The exact cause of the fires is still unknown.

Wildfire burns near Glen Ellen, CA. Credit: The SF Chronicle