Weekend weather: Cool, with frost possible in northern Minnesota
It’s great to see the blossoms on many trees this time of year. I might be appreciating the blossoms even more this year, after our delayed spring warmup.
Temperatures will retreat this weekend, and some spots in northern Minnesota will see frost. Low temps early Saturday morning are forecast to reach the 30s in much of northern and central Minnesota and parts of northwestern Wisconsin:
Saturday morning forecast lows
National Weather Service
Frost advisories have been issued for early Saturday from northwestern Minnesota through most of northeastern Minnesota:

Frost advisory (lighter blue) from 1 am to 9 am Saturday
National Weather Service

Frost advisory (blue) from 1 am to 9 am Saturday
National Weather Service
The green shaded area from International Falls through Ely is in a frost advisory plus a flood warning. Details on frost advisories and flood warnings can be found at the Duluth NWS site.
It is not uncommon to see frost in late May in northern Minnesota. The Minnesota State Climatology Office has information on average frost dates for many locations in Minnesota. You can click on a location at the linked site and look for the median date of the final 32 degree reading at that location. I should mention that official temps are measured at 5 feet above the ground and that the temperature at ground level can be several degrees colder than the official temp when the winds are light.
Chilly air lingers all weekend
Our average May 21 high temp is 71 degrees in the Twin Cities. We’re expecting metro area highs in the mid 50s this Saturday. Much of Minnesota and western Wisconsin will see Saturday highs in the 50s, with 40s in most of northern Minnesota:

Saturday forecast highs
National Weather Service
Lows temps late Saturday night and early Sunday morning will be in the 30s across much of Minnesota, with lower 40s from the metro area into southeastern Minnesota:

Sunday morning forecast lows
National Weather Service
Sunday highs will be mainly in the 50s:

Sunday forecast highs
National Weather Service
Any chance or rain this weekend?
A few very scattered showers are possible in Minnesota and western Wisconsin Saturday afternoon and evening. Sunday looks dry.
Programming note
You can hear my live weather updates on MPR News at 7:35 am, 9:35 am and 4:39 pm each Saturday and Sunday.
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