Bitterroot snowpack quickly vanishing; Clark Fork still in minor flood stage

The Clark Fork River remains in flood stage and the mountain snowpack is quickly vanishing in the Bitterroot Mountains, prompting local officials to turn an eye toward the summer fire season.

But with a low pressure system moving into the region, rising water remains a concern, Missoula County officials said Tuesday.

“We have lost an alarming amount of snowpack just in the last 72 hours,” said Adriane Beck, director of emergency services. “The Bitterroot is sitting at about 40% of snowpack where they were sitting at about 100% before this last warm up.”

While the Bitterroot basin has fallen to just 44% of normal snowpack for this time of year, the Upper Clark Fork basin remains at 95% of normal. The Lower Clark Fork basin was listed at 154% of normal on Tuesday morning.

The rapid loss of snowpack in the Bitterroot range so early in the season could be an issue later in the year.

“We're not concerned about that from a drought perspective, but it is below normal for this time of year,” Beck said. “We're continuing to get predictive and forecast for what we anticipate for fire season. Typically we'll have an indication on what we're in for by late June or early July.”

A flood advisory was issued for portions of Clark Fork River near Missoula two weeks ago, and minor flooding has occurred in the typical areas of the valley.

The Clark Fork River below Missoula remained well below the action stage on Tuesday, but the Clark Fork above Missoula was still listed at 8.5 feet in the minor flood stage.

It's forecast to fall below flood stage – 7.5 feet – on Saturday.

“But we do have rain in the forecast and low pressure coming in,” said Beck. “Indications are right now that we'll go back into flood stage early next week.”