Snow water percentages explained

In order to stem any alarm over numbers, Hot Springs County Emergency Management Coordinator Bill Gordon recently explained what is happening with the Snow Water Equivalent (SWE) percentages in the Wind River Mountains. The SWE is the amount of water contained in the snowpack.

As of May 15, the SWE was 210 percent. On May 22, is was 304 percent, and on May 29 it was 410 percent. It is important to understand the climbing percentages does not reflect increasing snow depth or SWE amounts.

Though the amount of snow in the mountains has not increased dramatically in the past three weeks, the percentage has doubled. Historically, snowmelt would have begun by now and a reduction in SWE would have begun. This year, the melt is a bit later than normal. The percentages seen are simply how this year's snow info compares to the historical median from 1981-2010. It is not an indicator that we are facing an ever-growing SWE.

The forecast is for slightly warmer temperatures up high this week. Gordon stated, “I believe by late this week we will see increasing runoff from the Wind River Mountains into Boysen as well as the western streams here in Hot Springs County.”

The Bureau of Reclamation is formulating their operations plan for June 1. Gordon has a call with the bureau on Friday.

Releases from Boysen Dam are expected to remain at 7,000 cubic feet per second until at least Thursday, when the Bureau of Reclamation will release the June forecast.

Slightly warmer temperatures this week in the western end of the county above 9,000 feet should begin the runoff of Owl Creek, which will be monitored visually and via gauges. Gooseberry and Cottonwood should increase as well. Sandbag production and distribution contingency plans are in place, but are on standby as of Tuesday afternoon.