MISSOULA (AP) — The flooding caused by melting snow and rain has receded after swamping areas near Helena, Missoula and northern Montana, but weather forecasters warn it will be a temporary reprieve as warm temperatures melt the snowpack at higher elevations.
The National Weather Service has issued warnings and advisories through the weekend with rivers and streams expected to rise in western and central Montana into next week.
“The real runoff hasn’t really even begun yet,” National Weather Service meteorologist Genki Kino told Montana Public Radio.
Near-record snowfall fell across much of the state over the winter, and some of the snowpack melted at low and mid-level elevations as the weather warmed and rain storms passed through in April.
Temperatures in the 70s starting today will cause more snowmelt at higher elevations, which will affect western Montana waterways like the already swollen upper Clark Fork River, which flooded a neighborhood in Missoula earlier in the week.
The Bitterroot River, which hasn’t seen any significant flooding yet this spring, also is expected to reach flood stage next week as the heat melts the snowpack in the Bitterroot Mountains.
“When you have 55 inches of snowpack, you can almost imagine from now into mid-June to early July as getting 55 inches of rainfall onto the surface,” meteorologist Alex Lukinbeal said. “That’s a lot of water that going to be put into the river system.”
Some flooding is also expected in areas around Seeley Lake and the Blackfoot River.
In central Montana, high-elevation snowmelt is expected to cause streams to rise near Helena, Wolf Creek, Augusta, Lincoln and in Meagher County over the weekend.
In northern Montana, where the Milk River has seen significant flooding for a couple of weeks, the floodwaters were receding except for between Tampico and Glasgow. That stretch is expected to see moderate flooding into next week, according to the weather service.
On Wednesday, Gov. Steve Bullock declared a statewide flooding emergency, allowing him to use state resources and the Montana National Guard for flood protection.