On the first day of the Sonoma and Napa fires, smoke colors the sky at sunset on Rodeo Beach. The October 2017 Northern California wildfires, also known as the Northern California firestorm, were a series of 250 wildfires that started burning across the state of California, United States, beginning in early October. 21 of the wildfires became major fires that burned at least 245,000 acres (99,148 ha). The wildfires broke out throughout Napa, Lake, Sonoma, Mendocino, Butte, and Solano Counties during severe fire weather conditions, effectively leading to a major red flag warning for much of the Northern California area. Seventeen separate wildfires were reported at that time. These fires included the Tubbs Fire (which grew to become the most destructive wildfire in the history of California), the Atlas Fire, Nuns Fire, and others.