Record-breaking Sierra heat giving way to storms

RENO — Record-breaking heat is expected to give way on Wednesday to thunderstorms capable of producing flash flooding around Reno, Lake Tahoe and much of the Sierra Nevada.

The National Weather Service issued a flash-flood warning shortly after noon on Tuesday along the Nevada-California line, where a storm dumped more than an inch of rain in less than an hour in central Mono County east of Yosemite National Park.

There were no immediate reports of damage. But authorities said travel could be affected on a 10- to 20-mile stretch of California Highway 120 east of Lee Vining, California.

A flash-flood watch goes into effect Wednesday morning for areas in and around Lake Tahoe, Reno, Carson City, Sparks, Gardnerville, Virginia City as well as the California towns of Bridgeport and Mammoth Lakes.

“Abundant moisture and light winds aloft will lead to slow-moving thunderstorms with heavy rain,” the weather service said.

“The areas at greatest risk for flash flooding are near small creeks and streams, urban areas and recent burn scars, such as the Bison Fire in Douglas County,” the service said. “Heavy rain may also lead to rock and mud slides near steep terrain (which) may impact travel over mountain passes.”

The Bison fire burned roughly 43 square miles and forced the evacuation of more than 75 homes in Douglas and Lyon counties in the Pine Nut Mountains last July. The burned areas are especially susceptible to erosion.

High temperatures were forecast in the upper 90s Tuesday through Thursday around Reno, where 42-year-old records fell with highs of 103 on Sunday and 105 on Monday.

Several other cities also set records on consecutive days, capped by highs on Monday of 108 in Lovelock, 107 in Yerington, 106 in Fallon and 103 in Carson City

Even California mountain towns above 6,000-feet elevation around Lake Tahoe saw unusually hot weather, with records set Monday at Truckee (97) and Tuesday at South Lake Tahoe (92).