• The Mosquito Fire, has burned more than 70 square miles since Tuesday and was just 10% contained.
  • Fire officials warned that vegetation in the area –from fine grass to big trees – was extremely dry and burning readily.
  • Helicopters flew water-dropping missions, providing assistance to firefighters on the ground.

A massive Northern California wildfire was threatening thousands of mountain homes Monday as the state and much of the West continued to grapple with the effects of historic drought.

In Northern California, the Mosquito Fire has burned more than 70 square miles since Tuesday and was just 16% contained as of Monday night. The steep, rugged terrain makes it difficult for ground crews to access the fire. The area was cooling off after record-breaking heat last week, but fire officials warned that vegetation in the area – from fine grass to big trees – was extremely dry and burning readily.

“This is not a weather show, it is a fuels show,” the California Department of Forestry and Fire Protection (Cal Fire) said in a fire status update. 

5,800 buildings at risk; 11,000 residents told to evacuate

Helicopters flew water-dropping missions, providing assistance to firefighters on the ground. Cal Fire incident Commander Rick Young took a reconnaissance flight over the fire and said diminished wind was helping slow the fire’s growth.

“The fire wasn’t going anywhere fast, but where it was burning, it was really burning,” Young said.

More than 5,800 buildings in Placer and El Dorado counties were threatened, and  11,000 residents were under evacuation orders. The fire also covered a swath of the Northern Sierra region with smoke. California health officials urged people in affected areas to stay indoors where possible.

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Organizers of the Tour de Tahoe canceled the annual 72-mile bicycle ride around Lake Tahoe because of the smoke from the blaze more than 50 miles away. Last year’s ride was also canceled because of smoke from a fire south of Tahoe.

Southwest winds could push the fire to the northeast later Monday, Cal Fire said.

“With clearer air in the afternoon, fire activity is predicted to increase as it has in the past several days,” the update warned. Cal Fire hopes to fully contain the fire by Oct. 15.

LABOR DAY FIRES:California wildfires kill 4 over Labor Day weekend amid record-breaking temperatures

Heavy rains from Kay swamp parts of Southern California

In Southern California, drenching weekend rains from Tropical Storm Kay created another problem: Los Angeles County firefighters, in some cases aided by helicopters, rescued about 50 people who became stranded Sunday in two dozen vehicles in a mudslide near Lake Hughes.