Snowmelt might break records across the state

Apr 9, 2017 From staff and wire reports

Record amounts of water are predicted to come down Wyoming mountains in a number of major river basins this spring and summer, according to the latest spring flood outlook.

Record runoff is expected in the Wind, Green, Sweetwater and Shoshone river basins because of the snowpacks that have accumulated this past winter, said Lee Hackleman, a water supply specialist with the Natural Resources Conservation Service.

"I don't remember having ever, since 2005 anyway, reporting record flows or projecting them, and here there must be a dozen places that are going to be record flows this year," Hackleman said Friday.

The overall snowpack in the state stood at 114 percent of median this week.

The snowpack in the Wind River Mountains was sitting at 198 percent of median early in the week, and there has been more snow in the mountains this weekend.

"Seems like every time snow comes in this year, it always has the Wind Rivers catching it," Hackleman said. "I think that's why they're so high. They're just in the right place to catch everything this year."

Hackleman said he expects many areas to see high water when the snowpack starts to melt in earnest later this spring and summer when warmer temperatures start melting the deep snow up closer to the 10,000 foot elevations in the mountains.

But whether there will be severe flooding depends on weather conditions, which play a big role in determining when and how quickly the snow melts, he said.

"No matter what, we're going to have some high flows, but we might not have flood flows if it comes off right," Hackleman said.

Some years it doesn't snow in April or May, and there are no problems with the runoff, Hackleman said.

However, that doesn't appear to be the case so far this year.

The National Weather Service posted a winter storm warning through Saturday night for the Teton, Gros Ventre, Wyoming, Salt River and Wind River mountains. More than a foot of heavy, wet snow is possible.

Flooding has already occurred along some rivers and streams in western Wyoming this spring from melting of low-elevation snowpack.