Duluth, MN Weather
Duluth hourly forecast: next 24 hours
Today's high of 66°F (19°C) is about 3°F (2°C) below the typical September high of 69°F (21°C).
Current conditions in detail
Duluth weather tomorrow (Wednesday, September 16)
Tomorrow in Duluth looks sunny, with a high of 56° and an overnight low of 48°. Precipitation chance is modest at 19%. Winds top out near 11 mph, and the UV index reaches 4 (moderate).
Duluth 14-day forecast
About the weather in Duluth
Duluth runs one of the wider annual swings in our dataset: 30°C separates the average July from the average January. Afternoons reach 78°F (25°C) at the peak of summer and 22°F (-6°C) at the depth of winter, with 113 days of measurable precipitation through the year.
Duluth weather: quick facts
- Hottest month: July - highs near 78°F (25°C)
- Coldest month: January - highs near 22°F (-6°C)
- Decade extremes (2015-2024): 97°F (36°C) high · -30°F (-34°C) low
- Wettest month: August (10 rainy days) · Sunniest: July (12.6 h sun/day)
- Climate type: humid continental
- Annual swing: 30°C between the average warmest and coolest month · day to night: 8°C
- Snow: about 27 days a year
- Months with freezing average lows: 6
- Average humidity: 73%
Temperatures through the year
Four of the twelve months pair mild highs with fewer than twelve wet days; the longest unbroken run is June through September. Warmth peaks in July: highs of 78°F (25°C), lows of 63°F (17°C). January bottoms out at 22°F (-6°C) in daylight, 9°F (-13°C) after dark. Overnight lows average at or below freezing for 6 months, November through April.
Rain, sun and snow
Snow falls on roughly 27 days a year, mostly October through May. Between the average July and the average January lie 30°C, a wider spread than 97% of the 3496 cities in our dataset. July is the brightest month at 12.6 hours of sun a day, against an annual average of 8.3 - duller than about 75% of the cities we track. Across the gridded 2015-2024 daily record, the highest daily maximum for this location was 97°F (36°C) and the lowest daily minimum -30°F (-34°C).
Season by season
Spring (March through May)
Spring in Duluth runs cold, with daytime highs averaging 48°F (9°C) and nights around 33°F (0°C); expect showers on roughly 30 days across the season, plus about 8 snowy days.
Summer (June through August)
Summer is pleasantly warm here - highs near 75°F (24°C), nights near 60°F (16°C), and rain falls on around 32 of the 90 days. Daylight is generous - around 11.9 hours of sun a day.
Fall (September through November)
Fall in Duluth runs cool rather than cold, with daytime highs averaging 55°F (13°C) and nights around 43°F (6°C); expect showers on roughly 29 days across the season, plus about 4 snowy days.
Winter (December through February)
Through winter, Duluth is bitterly cold: 25°F (-4°C) by day, 11°F (-12°C) after dark, and expect showers on roughly 22 days across the season, plus about 15 snowy days. Wind sharpens cold like this considerably; pair the forecast winds with the wind speed converter to judge exposed conditions.
Average temperatures in Duluth by month
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 22° | 9° | 6 | 1.0 in | 5.2 h/day | 78% |
| February | 24° | 8° | 6 | 1.2 in | 7.1 h/day | 72% |
| March | 37° | 22° | 7 | 2.1 in | 8.3 h/day | 70% |
| April | 46° | 32° | 11 | 2.9 in | 8.4 h/day | 69% |
| May | 60° | 44° | 11 | 3.6 in | 10.2 h/day | 70% |
| June | 71° | 55° | 11 | 3.6 in | 12.2 h/day | 72% |
| July | 78° | 63° | 10 | 3.4 in | 12.6 h/day | 73% |
| August | 75° | 62° | 10 | 3.8 in | 10.8 h/day | 74% |
| September | 69° | 56° | 10 | 3.5 in | 9.2 h/day | 75% |
| October | 54° | 43° | 10 | 3.0 in | 6.5 h/day | 72% |
| November | 40° | 29° | 9 | 2.5 in | 5.1 h/day | 72% |
| December | 28° | 16° | 10 | 2.6 in | 4.2 h/day | 78% |