Weekend weather: Colder with rain, rain-snow mix Saturday, Sunday

Our summery stretch is ending.

Friday was the fourth consecutive day with Twin Cities high temperatures in the 80s. Minneapolis-St. Paul International Airport reported a Friday high of 83 degrees. The average Twin Cities high temperature is just 56 degrees this time of year.

There were a lot of 80s Friday afternoon in south-central and southeastern Minnesota and into west-central Wisconsin. Much colder air is lurking to the west and northwest, with 50s and 40s in west-central and northwestern Minnesota.

Temperature trends

Saturday highs will range from upper 30s in northwestern and west-central Minnesota to lower 60s in far southeastern Minnesota:

Most of the Twin Cities metro area will see Saturday highs in the 50s. It’ll also be breezy on Saturday.

Sunday high temps will be mainly in the 40s, with some 30s in northeastern Minnesota and northwestern Wisconsin:

Sunday will be windy, with wind gusts over 40 mph in some areas.

Monday highs will be mainly in the 50s, with 40s in far northern Minnesota and western Wisconsin:

Twin Cities metro area highs are projected to reach the upper 50s Tuesday and Wednesday, followed by lower 50s Thursday and Friday.

Rain and snow chances

Areas of showers and embedded thunderstorms will continue to develop in Minnesota and western Wisconsin Friday evening and overnight Friday night.

Periods of rain with embedded thunderstorms are expected in most areas on Saturday, with some snowflakes in the mix over western Minnesota.

Many areas will see periods of rain or a rain-snow mix Saturday night, then much of eastern Minnesota and western Wisconsin will see periods of snow or a rain-snow mix on Sunday.

The National Oceanic and Atmospheric Administration’s North American Mesoscale (NAM) forecast model shows the potential precipitation pattern from 4 a.m. Saturday to 10 p.m. Sunday:

Snow amounts will probably be one inch or less in most areas, but far northeastern Minnesota could see a few inches of snow, mainly Saturday night into early Monday:

Some forecast models show higher snow totals, so check forecast updates.

You can find updated weather information for Minnesota and western Wisconsin on the MPR News network.

River levels

Rivers have already reached flood stage in parts of Minnesota and northwestern Wisconsin. You can see the river levels at various locations in northern Minnesota and northwestern Wisconsin here.

This is how the linked map looked Friday afternoon:

You can find info on river levels at various locations in central and southern Minnesota here.
Here’s how the linked map looked Friday afternoon:

You can zoom in on the linked map page and get detailed info on river levels at a specific location.

I should mention that river levels are measured in relation to the height above a local benchmark. In some locations, river levels are listed in feet above sea level.

Here’s the hydrograph of recent, current and forecast levels for the Mississippi River at St. Paul:

A rise of more than 7 feet is expected at that location in the next seven days, with additional rises possible beyond that point. The forecast level is 18.3 feet on Friday, which is at major flood stage.

Here are the results when various river levels occur at the St. Paul gauge:

Here’s the hydrograph of recent, current and forecast levels for the St. Croix River at Stillwater, Minnesota:

A rise of about 5 feet is expected in the next four to five days, with the river reaching major flood stage of 89.9 feet.

Here are the results of various river levels at the Stillwater gauge:

Rainfall and snowfall amounts will affect river levels.

Here are the historic St. Croix River crests at the Stillwater gauge:

Programming note

You can hear my live weather updates on MPR News at 7:35 a.m., 9:35 a.m. and 4:39 p.m. each Saturday and Sunday.