Climateby Month

Bismarck, ND climate by month

NOAA 1991-2020 normals · 1,695 ft elevation

Bismarck has warm summers and very cold and snowy winters. Highs peak at 85°F in July and fall to 23°F in January. Wet days are spread through the year, from about 7 to 12 a month. Normal snowfall is about 51 in a year. By our comfort score the best month is May.

Warmest month
85°F
July normal high
Coldest month
2°F
January normal low
Wet days a year
100
19.1 in of precipitation
Snow a year
50.5 in
normal snowfall

How warm is Bismarck?

Normal highs range from 23°F in January to 85°F in July.

0°20°40°60°80°100° January: normal high 23°F (-5°C), low 2°F (-17°C) 23° 2° February: normal high 28°F (-2°C), low 7°F (-14°C) March: normal high 41°F (5°C), low 19°F (-7°C) April: normal high 56°F (13°C), low 30°F (-1°C) May: normal high 68°F (20°C), low 42°F (6°C) June: normal high 78°F (26°C), low 53°F (12°C) July: normal high 85°F (29°C), low 58°F (14°C) 85° 58° August: normal high 84°F (29°C), low 56°F (13°C) September: normal high 73°F (23°C), low 46°F (8°C) October: normal high 57°F (14°C), low 33°F (1°C) November: normal high 41°F (5°C), low 19°F (-7°C) December: normal high 28°F (-2°C), low 8°F (-13°C) JFMAMJJASOND

Bars run from the normal low to the normal high for each month.

How rainy is Bismarck?

June has the most wet days (about 12); the year brings about 19 in of precipitation.

January: 8 wet days February: 8 wet days March: 8 wet days April: 8 wet days May: 10 wet days June: 12 wet days 12 July: 10 wet days August: 8 wet days September: 7 wet days October: 7 wet days November: 7 wet days 7 December: 8 wet days JFMAMJJASOND

Wet day: at least 0.01 in of rain or melted snow, counted from daily records 1991-2020.

How much does it snow?

Normal snowfall is 50.5 in a year, most of it in December.

January: 8.9 in of snow February: 7.5 in of snow March: 8.5 in of snow April: 4.6 in of snow May: 0.4 in of snow June: 0.0 in of snow 0.0 July: 0.0 in of snow August: 0.0 in of snow September: 0.0 in of snow October: 2.5 in of snow November: 8.0 in of snow December: 10.1 in of snow 10.1 JFMAMJJASOND

How humid is Bismarck?

Muggy days peak in July, at about 4 days.

January: 0 muggy days 0 February: 0 muggy days March: 0 muggy days April: 0 muggy days May: 0 muggy days June: 1 muggy days July: 4 muggy days 4 August: 2 muggy days September: 0 muggy days October: 0 muggy days November: 0 muggy days December: 0 muggy days JFMAMJJASOND

Muggy day: daily mean dew point of 65°F or higher, from hourly observations 1991-2020 at Bismarck Municipal Airport, 2.2 mi SE of the city center.

How much daylight?

Daylight ranges from about 8.6 hours in December to 15.8 hours in June.

January: 9.0 hours of daylight February: 10.3 hours of daylight March: 11.9 hours of daylight April: 13.6 hours of daylight May: 15.1 hours of daylight June: 15.8 hours of daylight 15.8 July: 15.4 hours of daylight August: 14.2 hours of daylight September: 12.6 hours of daylight October: 10.9 hours of daylight November: 9.4 hours of daylight December: 8.6 hours of daylight 8.6 JFMAMJJASOND
See all numbers
Monthly climate normals and day counts for Bismarck, 1991-2020
MonthHighLowPrecip.Wet daysSnowMuggy daysDaylight
January 23°F2°F 0.5 in8 8.9 in 0 9.0 h
February 28°F7°F 0.5 in8 7.5 in 0 10.3 h
March 41°F19°F 0.8 in8 8.5 in 0 11.9 h
April 56°F30°F 1.3 in8 4.6 in 0 13.6 h
May 68°F42°F 2.5 in10 0.4 in 0 15.1 h
June 78°F53°F 3.4 in12 0.0 in 1 15.8 h
July 85°F58°F 3.1 in10 0.0 in 4 15.4 h
August 84°F56°F 2.5 in8 0.0 in 2 14.2 h
September 73°F46°F 1.7 in7 0.0 in 0 12.6 h
October 57°F33°F 1.4 in7 2.5 in 0 10.9 h
November 41°F19°F 0.7 in7 8.0 in 0 9.4 h
December 28°F8°F 0.6 in8 10.1 in 0 8.6 h

High and low: NOAA 1991-2020 normal daily high and low. Wet days: at least 0.01 in of rain or melted snow. Muggy days: daily mean dew point 65°F or higher.

Best months to visit Bismarck

By our comfort score, the best month is May.

Comfort score by month (0-100) and its parts, in days per month
MonthScoreComfortableNotable rainHot or cold
Jan 260227
Feb 310222
Mar 432215
Apr 61844
May 761661
Jun 721463
Jul 60868
Aug 61947
Sep 691532
Oct 55834
Nov 361216
Dec 270225

Score = 40 × share of comfortable days + 25 × share of days without notable rain + 20 × share of days neither hot (90°F+) nor cold (high 40°F or below) + 15 × daylight. How the score works.

Frost dates in Bismarck

The last spring frost typically comes around May 14, and the first fall frost around Sep 27, leaving 136 frost-free days in a typical year.

Frost and freeze dates for Bismarck
Typical date1 year in 10
Last spring frost (32°F)May 14after May 27
First fall frost (32°F)Sep 27before Sep 15
Last hard freeze (28°F)May 3after May 17
First hard freeze (28°F)Oct 5before Sep 22
Frost-free season136 daysunder 117 days

"Typical" is the date with a 50% chance of a later spring frost (or earlier fall frost). Planting after the "1 year in 10" spring date gives a 90% chance of no further frost. The Old Farmer's Almanac publishes 30% dates, which fall between our typical and 1-in-10 dates.

Station: Bismarck (USW00024011), NOAA 1991-2020 freeze probabilities. Frost dates for every city in North Dakota.

Hottest and coldest readings, 1991-2020

The highest reading was 112°F (July 30, 2006); the lowest was -44°F (January 15, 2009).

From the temperature station's daily records with NOAA quality flags removed. Not an all-time record.

Near Bismarck

Similar climates elsewhere

Where the numbers come from

  • Temperature, rain, snowfall, snow depth, frost dates, humidity and wind by hour and cloud cover: Bismarck (USW00024011), 2.8 mi SSE of the city center, 1,658 ft . NOAA normals and daily records, 1991-2020.
  • Daily humidity and wind: Bismarck Municipal Airport (727640-24011), 2.2 mi SE of the city center, 1,651 ft . Hourly observations, 1991-2020.

Distances from the city center (USGS). Methodology · Report an error