Duluth, MN climate
Duluth has cold, snowy winters and pleasant summers. A typical July afternoon reaches 77°, a January night drops to 1°, and about 94 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decade6° warmer than normal today. The forecast high is 65°, and a typical Oct 1 in Duluth peaks around 59°.Live forecast: National Weather Service · Normal: NOAA 1991–2020
What a year in Duluth feels like
Winter
Spring
Summer
Fall
Duluth weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 19° | 1° | 1.0" | 18.6" | 10 | 31 | -2° – 23° |
| February | 25° | 4° | 1.0" | 17.8" | 9 | 29 | 4° – 29° |
| March | 36° | 15° | 1.5" | 12.3" | 9 | 28 | 17° – 38° |
| April | 49° | 27° | 2.5" | 9.0" | 9 | 14 | 31° – 45° |
| May | 62° | 38° | 3.2" | 0.9" | 12 | 1 | 46° – 55° |
| June | 71° | 48° | 4.3" | 0 | 12 | 0 | 56° – 62° |
| July | 77° | 54° | 3.9" | 0 | 10 | 0 | 60° – 71° |
| August | 75° | 53° | 3.5" | 0 | 10 | 0 | 58° – 67° |
| September | 66° | 45° | 3.3" | 0 | 11 | 0 | 48° – 60° |
| October | 52° | 34° | 3.0" | 2.8" | 12 | 2 | 37° – 47° |
| November | 36° | 21° | 1.9" | 10.6" | 10 | 13 | 20° – 39° |
| December | 24° | 9° | 1.4" | 21.6" | 9 | 29 | 4° – 26° |
| Year | 49° | 29° | 30.4" | 93.6" | 123 | 146 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Duluth
Duluth gets 30 inches of rain and melted snow a year. June is the wettest month and February the driest. Rain or snow falls on about 123 days a year. Snow covers the ground about 146 days of the year.
About 117 frost-free days a year
In half of years the last 32° night comes by May 27 and the first one by September 23. That leaves about 117 frost-free days for gardens, shorter than 98% of U.S. towns.
Heating and cooling a home in Duluth
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Duluth, 98% of that work is heating and 2% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Duluth and its neighbors
Duluth borders 3 towns with climate data. January nights across them vary by 3.7°. Alden has the coldest January nights (-1°) and Normanna the hottest July afternoons (77°). Duluth’s January low is 1° and its July high 77°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Duluth compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Duluth averaged 1.6° warmer than the 1900s. The biggest change is in December (+3.5°). The shift is larger than in 77% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Duluth’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. January swings the most: between 1991 and 2020 its average temperature ranged from -2° to 23°. June is the most reliable, staying within 6°.
Common questions about Duluth’s climate
What is the coldest month in Duluth?
January, with a typical high of 19° and a low of 1°.
What is the hottest month in Duluth?
July, with a typical high of 77° and a low of 54°. About 1 days a year reach 90°.
How much snow does Duluth get?
About 94 inches in a normal winter, most of it in December.
When is the first frost in Duluth?
In half of years the first 32° night comes by September 23, and the last spring frost by May 27.
What is the rainiest month in Duluth?
June, with 4.3 inches of rain and melted snow. The year totals 30 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Duluth itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Two Harbors 7nw, MN (13 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.