Rain adds to elevated rivers
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.