Lincoln County has declared a state of emergency, with the potential for minor flooding to worsen as rain and warm temperatures continue over the weekend.

The county commissioners on Wednesday passed the emergency resolution, although the county’s deputy emergency manager, Lisa Oedewaldt, said flooding has been minor so far.

“I think the biggest impacts, there could be runoff into the backs of people’s houses if they’re up against a mountain, and any drainage ditches that could be plugged with leaves or ice,” Oedewaldt said Thursday. “Unless the weather changes, I don’t see it changing for us until Monday.”

Rivers and creeks were swollen Thursday afternoon, following several days of rain and melting snowpack, and the state Department of Transportation reported mudslides and falling rocks temporarily halting road traffic near Libby and Eureka. Oedewaldt said only minor damage to structures had been reported so far, with localized flooding limited to low-lying areas including Education Way near Libby High School and portions of U.S. 2 near Troy.

The National Weather Service declared a flood watch in effect from Friday evening until Sunday afternoon in Lincoln, Sanders and Mineral counties, along with a portion of Flathead County west of Kalispell.

In an advisory released on Thursday, the Weather Service’s Missoula office warned that a round of heavy rain from Friday evening through Sunday morning could deliver well over an inch of precipitation along the Idaho border.

The agency’s 36-hour rainfall forecast predicted 1.3 inches in Troy, 1.2 inches in Noxon and nearly an inch in Libby and Trout Creek. By Thursday afternoon, many locations throughout Lincoln County had already received one-third to a half of an inch within the past 24 hours.

Oedewaldt noted that the county was distributing sandbags to area residents, and encouraged people to call the emergency management office at 406-293-6295 with questions and concerns.

While local rivers and streams are not expected to experience severe flooding, several stream gauges were already recording record or near-record water levels for the time of year. Major flooding events in the region typically occur later in the spring, as higher-elevation snow begins to melt more quickly.

At nearly 7 feet by Thursday afternoon, the Fisher River was running at a record high and was expected to crest just shy of its flood stage of 7.5 feet on Friday, according to data from the U.S. Geological Survey. The Yaak River was flowing at nearly four times its typical rate for the season by Thursday afternoon, but was expected to crest about a foot below its flood stage of 8 feet by Sunday evening.

In Sanders County, the Thompson River and Prospect Creek had both risen to seasonal records, but were predicted to subside after cresting about a foot below flood stage overnight on Thursday.

Reporter Sam Wilson can be reached at 758-4407 or by email at swilson@dailyinterlake.com.