Warmer temperatures and expected

rainfall this week could add to already swollen rivers and

streams.

Small streams and creeks across the

region are flowing high and fast, the National Weather Service in

Missoula reported.

Cooler nighttime temperatures eased

runoff last week, according to Bruce Bauck with the National

Weather Service, but that’s expected to change.

“Cold nights are very important in that

you don’t get the (snow) melt,” he said Friday.

The Stillwater River hit flood stage

last week before beginning to recede. The river peaked May 19 at

8.39 feet. Flood stage for the river is 7.5 feet.

By Monday the river had dipped below

flood stage, but was set to rise again possibly hitting flood stage

again as early as Wednesday.

“We’ll still see flooding in low-lying

areas and there are a few homes and roads being impacted by that

river,” Bauck said. “It’s slow to react. It takes a while for the

water to come off the hills and downstream into that river.”

The Whitefish River Monday was just

below 7 feet at the river’s mouth. Flood stage for the river is 8.5

feet.

The river is expected to rise and may

hit flood stage by the end of the week.

Record late snowpack levels continue to

impact runoff and flooding. SNOTEL sites, which have about 20 to 25

years of data, are showing the most amount of snowpack on

record.

“This is the most snow they’ve ever

seen this time of year,” Bauck said. “We’ve melted a little bit of

snow, but really there’s a lot left.”

Warmer nighttime temperatures are

anticipated to cause 24-hour snowmelt in higher elevations.

Two moist spring weather systems are

expected to bring heavy rain to northwest Montana this week. The

first was set to hit Tuesday and continue into Wednesday before

moving out of the area. Thursday and into the weekend the second

system is expected to arrive with the potential for heavy rainfall

of an inch or more.

Hydrologist Ray Nickless Monday said

monitoring of rivers and streams will be important this week.

“It’s looking like we’re going to have

high water on a lot of the streams as we come across with this next

event with precipitation and temperatures,” he said.

The Whitefish forecast is calling for a

chance of showers throughout the weekend. Highs are expected to be

in the mid-50s to low 70s.

Snow is predicted for higher mountain

passes of western Montana and north central Idaho Thursday.

Travelers should be prepared for slick road conditions on passes

including Marias Pass. Snow levels are expected to dip below 5,000

feet.