Typical Tahoe blue skies have been replaced by gray, smoky skies that could linger as fires outside the basin rage on.

Health officials say people with heart or lung disease, older adults, and children should reduce prolonged or heavy exertion while the smoke is so thick.

The Rim Fire near Yosemite is what is inundating the South Shore. That fire is raging, with firefighters having lost ground overnight. The fire has consumed more than 100,000 acres is 2 percent contained. It started Aug. 17. The cause is under investigation.

The American Fire near Foresthill has been bringing smoke to the North Shore and Truckee for days. That fire has consumed 20,232 acres and is 66 percent contained. Crews expect to have it fully contained Sept. 1.

— Lake Tahoe News staff report