Rivers to crest soon

With record high temperatures in the forecast, main rivers in Northwest Montana are expected to crest at the end of the week, some of them approaching flood stage.

But flooding is not expected, largely because of a spring runoff that has been gradual and orderly so far, said Ray Nickless, a hydrologist with the National Weather Service in Missoula.

"We've had this melt occur over the last two or three weeks at a lot of the mid-elevation sites," Nickless said. "And the low elevation sites have been melted out for a while now."

But now high temperatures are burning into the high elevation mountain snowpack. Record highs are forecast for Tuesday and Wednesday in Kalispell.

"Obviously, with these temperatures we're getting, the snowmelt is going to kick off at an accelerated rate," Nickless said.

In recent days, automated snow gauges in high elevation locations are measuring losses of up to 1 inch of snow water equivalent per day, Nickless said.

"That's like having an inch of rain on the mountain every day," he said. "But it's not creating a problem with the way it's coming off just because we've melted off such a huge volume of water over the last two or three weeks."

The Flathead River is forecast to rise right up to its flood stage of 14 feet at Columbia Falls on Friday. The Middle Fork Flathead River is projected to peak out two feet below flood stage that same day and the North Fork Flathead River is expected to rise up to flood stage at Polebridge by as early as Thursday morning.

In Lincoln County, the Yaak River is also expected to rise up to flood stage by Friday and then gradually taper off over the weekend.

Nickless said there is no additional water expected from rain during the week.

"We're pretty high and dry," he said. Scattered thunderstorms are possible by Friday, he said, but those tend to have a noticeable impact on small rivers and streams rather than large rivers.

Temperatures are expected to rise to 90 degrees in Kalispell today, which would easily break a record high of 86 degrees, set on May 16, 1973. Wednesday's forecasted high temperature of 88 degrees would exceed the May 17 record of 86 degrees, also set in 1973.

Reporter Jim Mann may be reached at 758-4407 or by e-mail at jmann@dailyinterlake.com