Warmer temps ahead for South Lake Tahoe; Rapid melting of snowpact expected

SOUTH LAKE TAHOE, Calif. - Temperatures will become very warm with highs near 80s in Lake Tahoe and above 90 degrees for most lower elevations Monday through Wednesday. Dry conditions are expected through Tuesday, then isolated afternoon and evening thunderstorms will be possible from Wednesday through next weekend.

The National Weather Service in Reno has issued a special statement due to the warming temperatures in the Lake Tahoe Basin and the rest of the Sierra Nevada: With temperatures rising well above normal through Wednesday, we will see a return to rapid melting of the high elevation snowpack. This will mean increased flows in the higher elevations and swift, cold flows for rivers and streams in the lower valleys by midweek from Lake Tahoe south through Mono County.

Due to the considerable snowpack remaining in the Walker River basin, minor flooding is possible later this week on the West Walker River above Topaz Lake. Below Topaz Lake and Bridgeport Reservoir, high flows are expected as well. Reservoir operations will have an influence on the flows through the Mason Valley, but current projections indicate the possibility of minor flooding near the Walker River by late in the week. Peak flows on the West Walker River are expected from late Tuesday night through early Thursday morning while peak flows farther downstream will be late in the week or next weekend.

To the north, there does not appear to be enough snowpack left to produce flooding along the unregulated portions of the Carson River system, or in the Truckee River system, but high flows are still likely for smaller streams in the Lake Tahoe Basin.

The high, cold flows may affect hikers and campers in and near the Sierra. The peak flows overnight may catch those camping close to creeks and streams off guard, so campers are advised to avoid setting up camp too close to creeks and streams. Hikers should be alert for snow bridges over creeks in higher elevations.

Their forecast for the week:

Monday- Mostly sunny, with a high near 81. Calm wind becoming northeast around 5 mph in the afternoon.

Monday Night - Mostly clear, with a low around 43. Northwest wind around 5 mph becoming calm.

Tuesday - Sunny, with a high near 84. Calm wind becoming south around 5 mph.

Tuesday Night - Mostly clear, with a low around 47. West wind around 5 mph becoming calm.

Wednesday - A 20 percent chance of showers and thunderstorms after noon. Mostly sunny, with a high near 82.

Wednesday Night - Partly cloudy, with a low around 44.

Thursday - Sunny, with a high near 76.

Thursday Night - Mostly clear, with a low around 44.

Friday - Mostly sunny, with a high near 76.

Friday Night - Partly cloudy, with a low around 43.

Saturday - Mostly sunny, with a high near 76.

Saturday Night -Partly cloudy, with a low around 44.

Sunday - Sunny, with a high near 77.