Evacuations underway in Napa County as lightning starts fires around Bay Area

Lightning strikes sparked multiple fires throughout the Bay Area on Monday, from the East Bay up north to Napa County, where 20 brush fires have been started by flashes from the sky. 

The Hennessey Fire quickly spread to 2,400 acres by Monday evening, resulting in mandatory evacuation orders. The fire is threatening 205 structures and is 0% contained. 

A second fire, the Gamble Fire had consumed 600 acres in an area near Berryessa Knoxville Road, west of Brooks, according to Cal Fire.

The Napa County sheriff's office ordered evacuations on Monday for Hennessey Ridge Road and Sage Canyon Road from Chiles Pope Valley Road to Lower Chiles Road.

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They also issued an evacuation warning for Highway 128 at Lower Chiles Valley Road to Turtle Rock and Highway 128 at Silverado Trl to Chiles Pope Valley Road including Pritchard Hill. 

A fresh vegetation fire popped up Monday morning in Alameda County at North Flynn and Comstock Road in Livermore.

Near Brentwood, homes were still being threatened by a cluster of fires called the "Deer Fire" in Contra Costa County in the shadow of Mount Diablo, which broke out on Sunday morning. As of Monday, it had burned 1,161 acres and was 0% contained. 

On Sunday night, authorities issued a mandatory evacuation order for homes along Marsh Creek and Morgan Territory roads.

East Contra Costa County Fire Battalion Chief Ross Macumber said there are up to 150 homes in that area that are "in the middle of the fire path, should the fire head that direction."

RELATED: Crews battling multiple vegetation fires sparked during Bay Area thunderstorm

One firefighter suffered a heat-related injury, but he is expected to be OK.

The other fire is in Alameda County called the "Marsh Fire" near Sunol, which firefighters say was likely started by Sunday morning lightning strikes. As of Monday, the weather was still a challenge as lightning strikes continued to flash in the background as firefighters worked to push back the blaze. As of early Monday, CalFire said the fire had grown to 850 acres with 0% containment. 

The Alameda County Sheriff's Office on Monday said a mandatory evacuation order is in effect for residents of Kilkare Canyon. Residents can head to the Residence Inn at 5200 Wolf House Road in Livermore. 

But so far, fire crews on the ground and in the air have managed to keep the flames in the hills, away from most homes.