The heavy precipitation of the past week has prompted National Weather Service officials to warn of continuing high water flows in the Wood River Valley and in other locations across south-central Idaho.
Around the valley, the rains caused creeks and rivers to rise midweek. On Wednesday, the Weather Service released a hazardous weather outlook warning of continuing elevated river levels throughout the region. The advisory covered the Big Wood and Little Wood River drainages. It also included rivers in the Sawtooth Valley, the Snake River Plain and other drainages across eastern Idaho.
Weather officials have been watching rivers across Idaho with a close eye as the extended cool and wet period has allowed area snowpacks to remain in place much longer than normal. Officials have warned of additional flooding once normal high summer temperatures arrive and the holdover snows finally begin to melt in earnest.
"Some of these rivers have reached or exceeded flood stage. Continue to monitor future flood statements for additional information on affected rivers," the Weather Service advisory states.
On Thursday, the Big Wood River was at 4.35 feet and was flowing at 2,050 cubic feet per second (cfs), as measured at the Bullion Street Bridge in Hailey. Official flood stage on the river is 6 feet.
Flows on the river have been rising steadily for the past week. On Saturday, June 4, it was running at 3.15 feet and 980 cfs, about half the current flows.
While high, the current flows are nowhere near the levels reached in 2006. After a winter of above-average snowfall, the Big Wood began overflowing its banks on May 16. It reached its peak on May 21, at 7.92 feet and a flow of 7,800 cfs. The flow exceeded any previously recorded volume.
In other erratic weather news across the region, the Weather Service released tornado warnings for Elmore and Camas counties. The Idaho Statesman reported winds of 80 miles per hour or more in an area southwest of Hill City in Camas County.
Weather officials were reportedly unable to find any evidence that an actual tornado touched down in Camas County.
Looking forward, the Weather Service office in Pocatello predicts that rivers will continue to remain at high flows through Tuesday.
"Some rivers will increase significantly due to moderate-to-heavy precipitation and continued snowmelt," the advisory states.
For the Wood River Valley, the Weather Service is calling for a 30 percent chance of showers and highs in the mid- to upper-60s through the weekend. Early next week, temperatures are expected to rise slightly to the lower 70s with a continuing chance of scattered showers and thunderstorms.