Bismarck, ND Climate & Monthly Averages

North Dakota, United States 🇺🇸 · humid continental climate
Annual avg
44°
Hottest month
July
Coldest month
January
Rainy days / yr
78
Sunshine
9.3 h/day
Right now: 83° and sunny - see live conditions

The climate of Bismarck

Bismarck runs one of the wider annual swings in our dataset: 32°C separates the average July from the average January. Afternoons reach 83°F (28°C) at the peak of summer and 24°F (-5°C) at the depth of winter, with 78 days of measurable precipitation through the year.

Climate quick facts

  • Hottest month: July - highs near 83°F (28°C)
  • Coldest month: January - highs near 24°F (-5°C)
  • Decade extremes (2015-2024): 100°F (38°C) high · -32°F (-36°C) low
  • Wettest month: June (8 rainy days) · Sunniest: July (13.5 h sun/day)
  • Climate type: humid continental
  • Annual swing: 32°C between the average warmest and coolest month · day to night: 10°C
  • Snow: about 18 days a year
  • Months with freezing average lows: 6
  • Average humidity: 66%

Temperatures through the year

The wettest month is June (2.7 inches (70 mm) across 8 days) and the driest January. July is the warm end of the year, averaging 83°F (28°C) by day and 63°F (17°C) overnight. January is the coolest month, with highs of 24°F (-5°C) and lows near 8°F (-14°C). Across the gridded 2015-2024 daily record, the highest daily maximum for this location was 100°F (38°C) and the lowest daily minimum -32°F (-36°C). Four of the twelve months pair mild highs with fewer than twelve wet days; the longest unbroken run is May through June.

Rain, sun and snow

2 months average under 20 mm of rain, the longest unbroken stretch running January through February.

How Bismarck compares

  • Its warmest and coolest months are 32°C apart - a wider seasonal swing than any other city in our 3496-city dataset.
  • Bismarck averages 44°F (7°C) across the year - cooler than all but 3% of the 3496 cities we track.

Ranked against every city in our dataset, each measured on the same ten-year window.

Monthly climate table

Monthly averages for Bismarck based on 2015–2024 weather data.
MonthHighLow Rain daysPrecipitation SunshineHumidity
January 24° 4 0.5 in 5.9 h/day 78%
February 27° 4 0.6 in 7.8 h/day 69%
March 40° 20° 6 0.9 in 8.9 h/day 68%
April 51° 31° 8 1.9 in 9.3 h/day 62%
May 67° 45° 10 2.6 in 11.4 h/day 61%
June 78° 57° 8 2.7 in 13.1 h/day 60%
July 83° 63° 8 2.1 in 13.5 h/day 62%
August 81° 60° 6 2.4 in 11.8 h/day 63%
September 73° 53° 7 2.0 in 9.9 h/day 63%
October 56° 38° 5 1.5 in 8.0 h/day 64%
November 40° 24° 4 0.8 in 6.5 h/day 70%
December 27° 12° 6 1.0 in 5.6 h/day 75%

Bismarck month by month

Bismarck weather in January

January brings highs around 24°F (-5°C), lows near 8°F (-14°C), about 4 wet days and roughly 2 snowy days - typically the coldest month and the driest month of the year in Bismarck.

Bismarck weather in February

February brings highs around 27°F (-3°C), lows near 8°F (-13°C), about 4 wet days and roughly 2 snowy days.

Bismarck weather in March

March brings highs around 40°F (4°C), lows near 20°F (-6°C), about 6 wet days and roughly 3 snowy days.

Bismarck weather in April

April brings highs around 51°F (11°C), lows near 31°F (-1°C), about 8 wet days and roughly 2 snowy days.

Bismarck weather in May

May brings highs around 67°F (19°C), lows near 45°F (7°C), about 10 wet days.

Bismarck weather in June

June brings highs around 78°F (26°C), lows near 57°F (14°C), about 8 wet days - typically the wettest month of the year in Bismarck.

Bismarck weather in July

July brings highs around 83°F (28°C), lows near 63°F (17°C), about 8 wet days - typically the hottest month and the sunniest month of the year in Bismarck.

Bismarck weather in August

August brings highs around 81°F (27°C), lows near 60°F (16°C), about 6 wet days.

Bismarck weather in September

September brings highs around 73°F (23°C), lows near 53°F (12°C), about 7 wet days.

Bismarck weather in October

October brings highs around 56°F (13°C), lows near 38°F (3°C), about 5 wet days and roughly 1 snowy days.

Bismarck weather in November

November brings highs around 40°F (5°C), lows near 24°F (-4°C), about 4 wet days and roughly 2 snowy days.

Bismarck weather in December

December brings highs around 27°F (-3°C), lows near 12°F (-11°C), about 6 wet days and roughly 4 snowy days.

Seasons in Bismarck

Spring (March through May)

Spring in Bismarck runs cold, with daytime highs averaging 53°F (11°C) and nights around 32°F (0°C); expect showers on roughly 24 days across the season, plus about 5 snowy days.

Summer (June through August)

Summer in Bismarck brings hot afternoons, with daytime highs averaging 81°F (27°C) and nights around 60°F (16°C); expect showers on roughly 23 days across the season. Daylight is generous - around 12.8 hours of sun a day.

Fall (September through November)

Through fall, Bismarck runs cool rather than cold: 56°F (14°C) by day, 39°F (4°C) after dark, and rain comes on about 16 days over the three months, plus about 3 snowy days.

Winter (December through February)

Winter in Bismarck brings deep cold, with daytime highs averaging 26°F (-3°C) and nights around 9°F (-13°C); rain comes on about 14 days over the three months, plus about 9 snowy days. Wind sharpens cold like this considerably; pair the forecast winds with the wind speed converter to judge exposed conditions.

Climate questions, answered

Does it freeze in Bismarck?
Average overnight lows sit at or below 0°C in 6 months of the year, November through April.
What should I wear in Bismarck?
It depends on the month: July runs to 83°F (28°C) while January holds at 24°F (-5°C). The full month-by-month breakdown is in the packing notes above.
When is the dry season in Bismarck?
2 months average under 20 mm of rain, with January the driest at 14 mm (0.5 in).
What is the average temperature in Bismarck?
44°F (7°C) across all twelve months - about 54°F (12°C) by day and 35°F (2°C) after dark.
How often does it rain in Bismarck?
About 78 days bring measurable precipitation, totalling 19.1 inches (485 mm). That works out at roughly 6.2 mm on an average wet day.

Best time to visit Bismarck

The best time to visit Bismarck is generally May to September, when these are the warmest and brightest weeks of the year. Daytime temperatures in that window sit near 76°F (25°C), with rain on about 8 days a month. For the same question asked the other way round, see where else is warm in May.

Pack for Bismarck with light clothing for the warm months, a heavy insulated coat, hat and gloves for winter and rain gear if you travel around June. Even in July, lows of 63°F (17°C) make an extra layer worth the space.

Bismarck temperature records (2015-2024)

Highest recorded
100°
in July
Lowest recorded
-32°
in January
Annual precipitation
19.1"
Snowy days / yr
18

Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.