Long Range Forecast for May 2021

May can be an extreme month for weather in Duluth, Minnesota. Just two years ago in May 2019 we had over 13″ of snow in Duluth (snowiest May on record) while in May 2016, Duluth recorded its earliest 90 degree temperature ever, with a high of 92 degrees on May 6th, 2016. Another 90 degree day occurred in May of 2018 on the 26th, high of 92 degrees. We can still see some snow and frost across the Northland in the month of May, but we can also see a few thunderstorms and even some severe weather in May.

Here’s a look at the Climate Normals and Records for May at Duluth, Minnesota

Normal Temperatures

May 1: High 57. Low 36.
May 31: High 67. Low 45.

Averages for May

Temperature: 51.4 degrees
Warmest: 57.7 degrees set in 2018
Coldest: 38.8 degrees set in 1907

Precipitation: 3.23″
Wettest: 7.99″ set in 1879
Driest: 0.15″ set in 1976

Snowfall: 0.4″
Snowiest: 13.3″ set in 2019

6 days in May have a high of at least 70 degrees
2 days in May have a high of at least 80 degrees

Note: Mean date for first 80 degree temperature in Duluth is May 23rd.
Note: Mean date for last 32 degree or colder temperature in Duluth is May 14th.

Astronomical Data for May

Sunrise on the 1st: 5:53 AM CDT
Sunrise on the 31st: 5:18 AM CDT

Sunset on the 1st: 8:19 PM CDT
Sunset on the 31st: 8:54 PM CDT

CFS model long range forecast valid for May 2021.

Temperatures: Near to Below normal across northeast Minnesota and northwest Wisconsin.

Precipitation: Above normal across northeast Minnesota and northwest Wisconsin.


Pleasant weather Friday; warm Saturday, windy and much cooler Sunday; a few rain chances through Sunday

  • A few showers will continue to move quickly SE through the Northland this evening followed by mainly dry conditions overnight and during the day Friday.
  • A few isolated showers are possible again Friday evening-early Saturday morning which will gave way to dry conditions during the day Saturday.
  • Rain chances return for Sunday, but possibly as early as Saturday night.
  • Near normal highs on Friday with highs in the 50s to around 60 degrees, will also have a lot less wind Friday compared to the gusty winds we saw in the Northland today.
  • Saturday continues to look like a warm one across the Northland as highs top out in the mid 60s to mid 70s with even a few upper 70s to near 80 degree temps possible across east-central Minnesota. Note: If we hit 70 in Duluth on Saturday, it would be the first 70 degree temperature this year. The average date for first 70 degree temperature in Duluth is April 28th.

Today, April 29th marked the 5th time so far this month with a high temperature of at least 60 degrees at Duluth, Minnesota. Note: The normal amount of 60 degree days in Duluth in April is 5 days.

A few showers will continue to move southeast across the Northland this evening but these showers should diminish by late this evening.

MRMS radar loop ending 6:40 PM CT, Thursday, April 29th, 2021.


I’ll start with the good news, and that would be the high temperature forecast for Saturday. Widespread warmth across the Northland, but temperatures near Lake Superior could go either way as they usually do in spring. An offshore wind direction=warm, while an onshore wind direction=much cooler temperatures. Computer models are in good agreement showing an offshore wind direction on Saturday which would lead to highs in the 70s even near Lake Superior for most of the day Saturday.

But don’t get use to these warm spring temperatures, because things change in big way on Sunday as highs will only be in the 30s to around 40 degrees near Lake Superior, and in the 40s and 50s across the rest of the Northland. Not only does it look a lot cooler Sunday, it also looks windy especially near Lake Superior where NE winds could gust to around 30 mph.

A few showers this evening, and again Friday night-early Saturday morning.

18z NAM 3km model simulated radar forecast ending 1 PM Saturday, May 1, 2021.


Milder temps on the way the next few days but cooler at times near Lake Superior; few showers possible Thursday and this weekend

  • Northeast winds will continue on Wednesday, but wind speeds look quite a bit lighter compared to what we’ve seen the last few days, end result from this should be for highs to climb into the 40s to around 50 degrees near Lake Superior on Wednesday while further inland highs will range from the lower 50s to around 60 degrees, with some middle 60s possible across northern Minnesota.
  • Some clearing is also expected on Wednesday with at least partially sunny skies expected across the entire Northland.
  • A few showers are possible Thursday as a cold front moves SE across the area. A wind shift to the NW will occur with the passage of a cold front on Thursday, so temps will warm into the 50s to around 60 degrees near Lake Superior on Thursday thanks to an offshore wind direction, while temperatures inland also top out in the 50s to lower 60s on Thursday.
  • East wind returns Friday and looks to continue through this weekend, so although temperatures away from Lake Superior will be nice Saturday and Sunday, ranging from the mid 60s to mid 70s in northeast Minnesota and northwest Wisconsin, locations near Lake Superior will be a lot cooler with highs both Saturday and Sunday generally in the 40s.
  • There could also be a few showers around the area Saturday and Sunday, but no widespread or persistent rains are expected this weekend the way it looks now.

Some light to moderate rain will affect parts of northwest Wisconsin tonight with rainfall amounts ranging from a trace to around a quarter inch in the black outlined area on map.

MRMS radar loop ending at 5:10 PM Tuesday, April 27th, 2021 shows some rain moving northeast and affecting parts of northwest Wisconsin late this afternoon, this rain is forecast to diminish by late this evening.

Another chilly late April day if you are near Lake Superior and also across northwest Wisconsin as overcast skies helped to keep temperatures in the upper 30s to middle 40s today, while some partial sun has allowed temperatures to rise into the 50s across northern Minnesota this afternoon.

A textbook radar signature of a tornadic supercell thunderstorm from this afternoon in northern Texas. This storm produced at least one tornado near Truscott, TX at 3:51 PM today, and this supercell thunderstorm also produced very large hail of baseball to tea cup size (2.75 to 3.00 inch diameter hail)

Radar was showing very strong rotation (red and blue colors on map) with a tornadic supercell this afternoon near Truscott, Texas.


Far northern Minnesota missed out on the precipitation over the last few days with only 0.01″ of precipitation reported at International Falls, while Duluth picked up 0.63″ of precipitation since Sunday night.


A Breezy and Cool NE wind continues near Lake Superior tonight and Tuesday with some fog and drizzle tonight; a few showers Tuesday mainly over northwest Wisconsin

5.47″ of precipitation has fallen in Duluth since March 1st, which is nearly +2″ above normal to date (+1.95″) or some 155% of normal through April 26th.

The only way we were going to start chipping away at our precipitation deficit (which was ~10″ going into 2021) in Duluth was by getting into a much more active weather pattern with more frequent precipitation events, and sure enough this is what has been happening in the Twin Ports since January 1st, with 6.61″ of precipitation so far this year which is +1.32″ above normal to date. No signs this pattern is gonna change much looking out the next two weeks as precipitation totals are forecast to be near to above normal across northeast Minnesota and northwest Wisconsin, so if and when we get a day without any rain, enjoy it, so Tuesday and Wednesday look to be those days as it looks dry in Duluth. We could see a few showers return on Thursday, and possibly some more showers at times this weekend.

  • Rain continues in northwest Wisconsin late this afternoon but this rain will be tapering off from west to east this evening.
  • Some more showers are possible Tuesday mainly over northwest Wisconsin and possibly in far eastern Minnesota.
  • It looks dry across northern Minnesota tonight and Tuesday.

18z NAM 3km model simulated radar forecast thru 7 AM Wednesday.


No doubt about it spring 2021 has been much wetter in Duluth compared to spring 2020 with just 2.16″ of precipitation last spring from March 1st to April 26th compared to nearly 5.50″ for the same period this spring.

Spring 2021 in Duluth is currently running +3.31″ wetter to date compared to spring 2020.

Spring 2021 has been a wet one in Duluth with several precipitation events (17 of them) for the period March 1st to April 25th.

  • Average date for first 70 degree temperature in Duluth is April 28th, so this year’s first 70 will occur a little later than normal, how much later? Time will tell. By the way last year’s first 70 in Duluth didn’t occur until May 20th!

48% of days this month have had a below average high temperature (blue), while 44% of days have had an above average high temperature (red) in Duluth.

April 2021 is running +2.4 degrees warmer than average thru April 25th.

The good news is that today is likely the coldest day will have in Duluth for the next 10 days, but the bad news is I don’t see anything too warm when it comes to our high temps through May 6th.

Will likely be dealing with an easterly wind as well on some of the days through May 6th so that will keep things cooler by the lake on the days we have an east wind.

Note: Normal highs in Duluth are in the mid to upper 50s and normal lows are in the mid to upper 30s from April 27th to May 6th.


…Precipitation Totals from April 25-26, 2021…

Note: Totals listed below are for the 24 hour period ending 5 PM Monday, April 26, 2021.

Source: https://mesowest.utah.edu/

  • Hill City, MN: 0.64″
  • Duluth Airport: 0.63″
  • Saginaw, MN: 0.60″
  • Barnes, WI: 0.58″
  • Brainerd, MN: 0.42″
  • Moose Lake, MN: 0.38″
  • Hinckley, MN: 0.37″
  • Grand Rapids, MN: 0.30″
  • Grand Marais, MN: 0.30″
  • Ashland, WI: 0.30″
  • Solon Springs, WI: 0.26″
  • Chisholm-Hibbing Airport: 0.25″
  • Siren, WI: 0.24″
  • Hayward, WI: 0.24″
  • Longville, MN: 0.18″
  • Bigfork/Effie, MN: 0.02″

…Snowfall Reports from Sunday night/Monday morning, April 25-26, 2021…

Note: On average, today’s date April 26th is when we typically see our last snowfall of at least 0.1″ in Duluth, however, the latest last 0.1″ or greater snowfall on record in Duluth didn’t occur until May 28th in 1965.

Source: https://www.weather.gov/dlh/

  • 11.8 NNE Duluth, MN: 1.5″
  • 9.8 W Ashland, WI: 1.1″
  • 4.4 W Grand Marais, MN: 1.0″
  • Babbitt, MN: 0.8″
  • Duluth Airport: 0.6″
  • Wolf Ridge, MN: 0.5″
  • Cook, MN: 0.4″
  • 3 E Wright, MN: 0.3″
  • Butternut, WI: 0.3″
  • Embarrass, MN: 0.2″

Well that is one strong warm front today! Temperatures this afternoon ranged from the mid 90s at Hill City, Kansas to the low and mid 30s along the North Shore of Lake Superior in northeastern Minnesota.

A large mid/upper level trough continues to move slowly east out of the western U.S. today while subtropical moisture (green arrow) lifts NE out of the Southern Plains.

Rain chances for the next few days will be greatest south of northeast Minnesota as a frontal boundary remains nearly stationary across the Midwest.

Water vapor loop from Monday, April 26th, 2021.


April 24th, 2021 Snowfall

A late season snowfall hit parts of northeast Minnesota Saturday morning, April 24th, 2021. This was an elevation type snow event, meaning areas close to Lake Superior (lower elevation) saw little to no snow accumulation as snow that fell melted on contact, while in higher elevation, snow accumulated to about an inch, with most of that snow accumulating on trees and grassy/elevated surfaces. Living in West Duluth (lower elevation) there was no snow accumulation Saturday morning. Apparently seeing snow in Duluth since October wasn’t enough for me, so I had to take a little drive Saturday morning to find some snow that accumulated, so I ventured south on Highway 23 to find the snow, and sure enough once I got past Fond du Lac the landscape looked beautiful as snow stuck to the trees and grassy surfaces. All of the pictures below were taken from just south of Holyoke, MN at Graham Lake, enjoy!