Rain, remaining snow still present flood threats

The Daily Inter Lake

Northwest Montana river levels are projected to drop this week, but there is potential for them to rise again, officials with the National Weather Service said Tuesday.

Meteorologist Peter Felsch said an incoming low-pressure trough was expected to bring lower temperatures and some rain today.

The cooler weather was expected to slow mountain snowmelt, and the rain is not expected to significantly increase river flows. However, that same system is expected to stall after it crosses the Continental Divide, with weather models showing it backing up and delivering more than 3 inches of rain along the divide this Friday.

If that happens, rivers in the Flathead Basin could rise again, said service hydrologist Ray Nickless.

Adding to that potential is the persistence of snow at high elevations.

Before warm weather arrived last weekend, the Emery Creek automated snow-measurement site - located at an elevation of 4,350 feet east of Hungry Horse Reservoir - had 11 inches of snow water content. By Tuesday, only one inch of moisture remained.

But the Flattop site at 6,300 feet in Glacier National Park had 52 inches of snow water content before the warm spell - and 47 inches remained on Tuesday.

The Noisy Basin site, at 6,040 feet along the Swan Crest, had 48 inches of snow water content last week and is now down to 42 inches.

"I would say we have that potential for rivers to come back up, especially with the low-pressure systems coming in with precipitation and having snow up in the mountains," Nickless said.