Between Tuesday and this morning, the wildfire in northern Napa County has grown from 3,200 to 4,300 acres, but firefighters have been able to maintain a 30-percent containment level over the last 24 hours. The Butts Canyon Fire, which broke out around noon on Tuesday, is scorching trees and brush in Pope Valley and an area to the northwest of Lake Berryessa, near the Lake County border.

Cal Fire is now saying that 380 structures are threatened, but so far only two residences and seven out-buildings have been destroyed.

As KTVU reports, more than 1,000 firefighters are on the scene with groups having arrived from fire districts including Hayward, Fremont, Oakland, Menlo Park, and Livermore-Pleasanton. More reinforcements are currently on the way from Los Angeles.

The Butts Canyon Fire is currently the largest wildfire burning in the state, and comes quite early in what's likely to be a bad fire season in a drought year. So far in 2014, state firefighters have counted 2,700 incidents, which marks a 50 percent jump from the 1,800 wildfires recorded during the same January to July period last year.