fbpx

Deep Snowpack Means Increased Chance for Spring Flooding

National Weather Service models suggest 70 percent chance of Flathead River hitting flood stage

By Justin Franz
The North and Middle Forks of the Flathead River converge at Blankenship Bridge north of Columbia Falls. Beacon file photo

A deep snowpack in the mountains and valleys of Western Montana has meteorologists raising concerns about spring flooding.

National Weather Service hydrologist Ray Nickless said the biggest potential for spring flooding lies in the Flathead and Clark Fork river basins. The current snowpack in the Flathead is 141 percent of normal, and forecasts call for more snow throughout March.

The snowpack is 156 percent above normal in the Upper Clark Fork region and 155 percent above normal in the Sun, Teton and Marias drainages.

Nickless, who gave a flood outlook presentation on March 8, said current models say there’s a 70 percent chance that the Flathead and Clark Fork rivers will hit flood stage this spring.

Numerous storms have kept much of Northwest Montana covered in the white stuff. As of March 8, snow was measured at 38 inches in West Glacier, 36 inches in Seeley Lake, 14 inches in Kalispell and even more in the surrounding mountains. Skiers on Whitefish’s Big Mountain have been rejoicing over one of the snowiest winters in recent memory. On Friday, the summit of Whitefish Mountain Resort had 151 inches of snow.

But that deep snow could lead to trouble in April and May, when the annual melt begins. Meteorologist Trent Smith said it’s still too early to tell what exactly will happen, but there is an “increased” chance of flooding this spring. A sudden spat of warm weather could result in rapid snowmelt that could push area streams and rivers over their banks. A sudden and significant rain event could also result in flooding.

Smith said the current snowpack situation is not unlike the one Northwest Montana had in 2011, the last time there was major flooding in the region.

“It all depends on what happens in May and June,” Smith said.