The Mosquito Fire producing a pyrocumulus cloud on the day after the blaze began near Oxbow Reservoir, on Mosquito Ridge Road in the Foresthill area.

DOWNIEVILLE - Ignited by an unknown cause on Tuesday, September 6, the Mosquito fire in Placer and El Dorado counties, roughly 40 miles due south of Downieville, had burned over 63,000 acres (nearly 100 square miles) of timber and chapparel by yesterday afternoon, September 14, and growth was mostly to the south and the eastern portions of the fire.

To control the conflaguration, over 3,000 personnel from the US Forest Service, CalFire, and numerous local fire departments are currently deployed and they are attacking the flames both from the air and on the ground.

The equipment dropping chemical fire retardants and water upon the fire include VLATs (Very Large Airtankers), Super Scoopers (delivering water from local reservoirs and a fleet of helicopters that also provide surveillance services to aid firefighters on the ground. A large number of dozers and heavy equipment are also working in the areas to the east of the fire to build indirect control lines ahead of the fire front advancing through extremely dry fuels.

Several small communities, numerous structures and energy infrastructure are threatened. As a consequence, evacuation orders and closures of many roads are in effect east of Auburn and southeast of Colfax. In addition, smoke from the fire has also resulted in spells of extremely unhealthy air for residents in Nevada and Sierra counties.

The fire is currently estimated to be 20 percent contained, with complete containment not expected until October 15.