While several rivers had initial crests below flood levels at the end of last week, a weekend mix of rain and snow could add to rising waters and possible second crests.

This past week, colder weather helped cities across the region avoid major high-water issues. Crests were lower than originally expected on the Mississippi River at Red Wing and the St. Croix River at Stillwater, where crests came in below flood stage.

But a weekend storm expected to extend into Monday could drop between a quarter of an inch to a half an inch of rain, in addition to a dusting of snow, and affect river forecasts.

The National Weather Service forecast rain that was expected to start late Saturday and continue into Sunday morning. Forecasters said there will be a break in precipitation during the day, but rain is expected to turn into snow overnight Sunday, with a chance of light snow into Monday morning.

But "amounts are looking like they won't be quite as much as we expected over the last couple of days," said Jim Richardson, a forecaster for the National Weather Service.

Rain amounts will be close to a quarter inch, Richardson said. Snow accumulation should not be significant in the metro. "It will be more rain," he said.

Still, because of saturated ground from snow melt and the coming precipitation, a flood warning was issued Saturday morning for the St. Croix River at Stillwater. Minor flooding is being forecast, but the river is not expected to rise above flood stage until next Saturday.

According to the Weather Service, second crests expected later this spring in Stillwater and Red Wing will be higher than the first crests.

While the Mississippi River has been falling in St. Paul since cresting on Wednesday, levels are expected to go back up again midweek. Closer to the weekend, levels may get back up to first crest stages, Richardson said.

In the south metro, the Minnesota River, which had been receding in past days, is expected to stay relatively level this week.

Flood warnings have continued throughout the Red River Valley, where rising temperatures have caused runoff to enter river systems. More runoff is expected to affect flood conditions this week.

Nicole Norfleet • 612-673-4495