By Jennifer Chaussee

BERKELEY Calif. (Reuters) - A Northern California wildfire started by a lightning strike a month ago has burned more than 108,000 acres in the drought-stricken state, officials said on September 12.

The fire in the Klamath National Forest started when lightning struck the Happy Camp area on August 11. It was 45 percent contained on September 12.

The blaze formed a large ring and grew by 882 acres on the night of September 11, said Klamath National Forest spokeswoman Andrea Capps, and it is expected to continue to grow along the ring's southern perimeter through September 12.

"We're in the third year of a drought so these are unprecedented conditions," she said. "We have put all of our resources out there ... but with the drought conditions it just means everything is so much more flammable."

Mandatory evacuations are still in effect along Canyon Creek Road, where residents have flocked to the Siskiyou County Fairgrounds and a nearby tribal community center.

Earlier this month, the fire destroyed four homes and four outbuildings. A smaller fire in another part of the forest has swallowed more than 9,000 acres and was just 22 percent contained on the morning of September 12, officials said.

Nearly 3,000 firefighters and other emergency personnel from around the country are battling the flames and have cleared dry grasses and brush from around the fire, but winds and dry conditions are expected to force it south through September 12, said Klamath National Forest spokeswoman Kerry Greene.

Using 13 helicopters, 73 ground crews and 124 fire trucks, officials said they expect to have the fire fully contained by Sept. 20. There were no reported injuries or deaths. 



(Reporting by Jennifer Chaussee; Editing by Daniel Wallis and Eric Beech)