Updraft® - Minnesota Weather News

Tracking weekend rainfall timing, coverage and totals

More needed rainfall for much of Minnesota this weekend

European model (ECMWF) rainfall forecast
European model (ECMWF) rainfall output by Monday morning.
ECMWF via pivotal weather

Thursday evening’s tropical downpours brought a nice light show with thunder, along with welcome rainfall to several locations in eastern and southwest Minnesota.

The highest rainfall totals favored areas east of Interstate 35 from the North Shore to the eastern Twin Cities. Another pocket of heavy rain fell in southwest Minnesota. Many reports of 0.5 to 1 inch came in, with some localized areas picking up more than 2 inches of rain.

Rainfall totals
Rainfall totals Thursday night.
Twin Cities National Weather Service

Rainfall totals around the Twin Cities area ranged from very little, to more than 2 inches in Woodbury in the eastern Twin Cities.

Twin Cities rainfall totals
Twin Cities rainfall totals
CoCoRaHS

Those areas that got under those big, fat, cathartic tropical raindrops last night picked up some valuable downpours.

Weekend rainfall timing and totals

A few waves of scattered rain and thunder will sweep across Minnesota this weekend. The heaviest rains appear to favor central and southern Minnesota.

Short-range forecast models suggest the first wave of rain and thunder moves into southwest Minnesota after midnight Friday night and rolls east into the Twin Cities area between about 6 and 10 a.m. Saturday morning.

NOAA’s HRRR model loop below tracks that initial rain and thunder wave east across southern Minnesota from 1 a.m. to 8 a.m. Saturday.

NOAA HRRR model between 1 am and 8 am Saturday
NOAA HRRR model between 1 a.m. and 8 a.m. Saturday
NOAA via tropical tidbits

Rainfall timing and coverage will be hit or miss the rest of the weekend. But most models suggest the most favorable timing and coverage for storms develops later Saturday afternoon across northern and central Minnesota and pushes into the Twin Cities again between about 10 p.m. and midnight Saturday night.

Here’s NOAA NAM 3 km model solution between 4 p.m. Saturday and 1 a.m. Sunday.

NOAA NAM 3 km model
NOAA NAM 3 km model between 4 p.m. Saturday and 1 a.m. Sunday.
NOAA via tropical tidbits

Rainfall totals

Forecast models again differ on rainfall coverage and totals. The European model paints widespread 0.5 to 1 inch rainfall totals with some local totals over 2 inches.

European model (ECMWF) rainfall forecast
European model (ECMWF) rainfall output by Monday morning.
ECMWF via pivotal weather

The Canadian model solution is more aggressive with rainfall in and around the Twin Cities. It cranks out local totals of more than 3 inches in some areas.

Canadian model precipitation output
Canadian model precipitation output through Monday morning.
Environment Canada via pivotal weather

With dew points in the upper 60s, there will be plenty of moisture this weekend to generate multi-inch rainfall in parts of Minnesota.

It’s like a game of rainfall bingo to see precisely where it falls. I know I’d be just fine with 2 or 3 inches of rain at the Weather Lab this weekend.

Severe risk

NOAA’s Storm Prediction center paints a slight severe risk across most of central and southern Minnesota Saturday.

Severe weather risk areas
Severe weather risk areas Saturday
NOAA/Twin Cities National Weather Service

The most favorable window for severe storms appears to be with the likely second wave that looks like it might blow up in west-central Minnesota Saturday afternoon. That wave should track across much of central and southern Minnesota through Saturday night and could put down large hail and some damaging wind gusts.

Keep the weather app, weather radio and MPR News handy this weekend.