Photo: Quintin Soloviev · CC BY 4.0Bismarck’s winters are colder and snowier than most of the U.S.
A typical July afternoon reaches 84°, a January night drops to 3°, and about 51 inches of snow falls in a normal winter.
A year in Bismarck at a glance
Each month’s typical high and low, and what it brings.
What stands out about Bismarck’s climate
Compared with towns across the U.S., with Bismarck’s place in North Dakota beside it.
What a year in Bismarck feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 136 frost-free days a year
In half of years the last 32° night comes by May 14 and the first by September 27. Frost and day counts come from NOAA’s station at Bismarck, ND, 3 miles from the city’s center point, at about the same height.
The 2023 USDA map puts Bismarck’s center in zone 4a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −26°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 51 inches of snow a winter
Snow, measured at Bismarck, ND, falls mostly in December. Precipitation (rain plus melted snow) adds up to 18 inches a year; June is the wettest month and February the driest. Rain or snow falls on about 100 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Bismarck
94% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through May.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Bismarck, ND.
Living with Bismarck’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
136 frost-free days in zone 4a. The last frost comes by May 14 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Sep 27.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 41 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Bismarck from natural hazards, river flooding is the largest share (33%); heat waves, cold waves, winter storms and ice storms together are 35%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Bismarck and its neighbors
Every town next door is within a degree of Bismarck in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Bismarck’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Bismarck, ND | 3° | 84° | 18" | 51" |
| Havre, MT | 6° | 85° | 13" | 41" |
| Moorhead, MN | 0° | 82° | 25" | 51" |
| Gunnison, CO | 0° | 82° | 12" | 50" |
| Huron, SD | 6° | 86° | 23" | 44" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Bismarck averaged 1.5° warmer than the 1900s. The biggest change is in January (+4.7°).
A bigger shift than in 62% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Bismarck compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Bismarck’s place among North Dakota’s.
Bismarck weather by month
Highs, lows and precipitation from NOAA’s grid at Bismarck’s center; snow, wet days and snow on the ground from Bismarck, ND. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 22° | 3° | 0.5" | 8.9" | 8 | 26 | 0° – 27° |
| February | 27° | 7° | 0.5" | 7.5" | 8 | 21 | −1° – 30° |
| March | 40° | 19° | 0.7" | 8.5" | 8 | 13 | 18° – 43° |
| April | 55° | 30° | 1.3" | 4.6" | 8 | 3 | 34° – 50° |
| May | 68° | 42° | 2.6" | 0.4" | 10 | 0 | 50° – 61° |
| June | 77° | 53° | 3.3" | 0.0" | 12 | 0 | 60° – 70° |
| July | 84° | 58° | 3.0" | 0.0" | 10 | 0 | 63° – 77° |
| August | 83° | 55° | 2.2" | 0.0" | 8 | 0 | 64° – 75° |
| September | 73° | 46° | 1.6" | 0.0" | 7 | 0 | 53° – 65° |
| October | 57° | 33° | 1.4" | 2.5" | 7 | 1 | 37° – 50° |
| November | 40° | 19° | 0.6" | 8.0" | 7 | 9 | 17° – 40° |
| December | 27° | 8° | 0.6" | 10.1" | 8 | 19 | 6° – 28° |
| Year | 54° | 31° | 18.2" | 50.5" | 100 | 92 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from -1° to 30°. June is the most reliable, staying within 10°.
Where Bismarck’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Bismarck’s center.
- Snow: Bismarck, ND.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Bismarck, ND, 3 miles from the city’s center point, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Bismarck’s climate
What is the weather like in Bismarck?
A typical July afternoon reaches 84°, a January night drops to 3°, and about 51 inches of snow falls in a normal winter. Colder January nights than all but 104 U.S. towns; cooler July afternoons than 65% of U.S. towns.
How cold does it get in Bismarck in winter?
January nights average 3°. About 184 nights a year reach 32° or below and 37 reach 0° or below. In the coldest January of the last 30 years the month averaged 0°.
How much snow does Bismarck get?
About 51 inches in a normal winter at Bismarck, ND, most of it in December, with snow on the ground about 92 days a year.
How hot does it get in Bismarck?
July, with a typical high of 84° and a low of 58°. About 21 days a year reach 90° and 2 reach 100° (Bismarck, ND).
When is the first and last frost in Bismarck?
In half of years the last spring frost (32°) comes by May 14 and the first fall frost by September 27, about 136 frost-free days, at Bismarck, ND.
What growing zone is Bismarck in?
Zone 4a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −26°.
What is the best time of year to visit Bismarck?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Bismarck getting warmer?
Yes: 1991–2020 averaged 1.5° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 62% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Bismarck.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.