Rivers are rising in Minnesota in a way not normally seen this time of year.

The St. Croix River reached more than 77.5 feet in Stillwater on Friday and started to spill over its banks, flooding portions of the riverwalk.

“This is what happens in the early spring, right?” Stillwater Mayor Ted Kozlowski said. “I don’t think we’ve ever seen this in December, January. I mean, this river’s always ice right now and there’s people fishing out here!”

Over the next few days, the St. Croix River is expected to reach nearly 80 feet, which is “action stage,” according to the river tracking charts issued by the National Weather Service. Flood stage is 87 feet.

“This is, for some rivers, the first time it’s ever happened that we’ve seen a river rise in December,” noted KSTP Meteorologist Chris Reece. “Don’t let the lack of snow distract you from the fact that this has been a very wet December. So while this has been the sixth-least snowy December we’ve had, it’s been the 12th wettest December we’ve ever had.”

Up in Moorhead, the Red River is expected to hit flood stage by Saturday.

Some streets in Moorhead are already shut down due to flooding.

There is not expected to be any major impact in Stillwater, beyond some sidewalk flooding.

“I did see, unfortunately, a couple people’s docks floating down the river the other day,” Kozlowski said.

Kozlowski said he is watching the forecast closely, as any extra rain or snow over the next week could take the river beyond action stage.

“That’s when it’s like, OK, now we have to start paying attention, right? Because if we’re at 680 feet above sea level and then we get another two or three-inch rain event, now we’re looking at, well, we might have to sandbag,” Kozlowski said.