Bismarck, North Dakota climate: Normal weather by month, frost dates and records
Bismarck's normal year runs from 2°F January nights to 85°F July afternoons, with 19.1 inches of precipitation and 51 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 6.2°C, January lows of −16°C, July highs of 29°C, 484 mm of precipitation a year.
- NOAA stationBismarck Municipal Airport
- Station IDUSW00024011
- Location46.77°N 100.76°W
- Elevation1,658 ft (505 m)
- From the center3 miles
- Population77,772
On October 22, the normal high in Bismarck is 54°F and the normal low 30°F, and the chance of measurable rain or snow is 23%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Bismarck.
- Jan 23° 2°
- Feb 28° 7°
- Mar 41° 19°
- Apr 56° 30°
- May 68° 42°
- Jun 78° 53°
- Jul 85° 58°
- Aug 84° 56°
- Sep 73° 46°
- Oct 57° 33°
- Nov 41° 19°
- Dec 28° 8°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Bismarck each month?
July is the warmest month, with normal highs of 85°F; January the coldest, with normal lows of 2°F. The most precipitation falls in June (3.36 in), the least in January (0.48 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 23°F | 2°F | 12.8°F | 0.48 | 8.9 | 8 | <1 | 31 | 9 h |
| February | 28°F | 7°F | 17.5°F | 0.52 | 7.5 | 8 | <1 | 28 | 10 h 20 min |
| March | 41°F | 19°F | 30.1°F | 0.84 | 8.5 | 8 | <1 | 28 | 11 h 50 min |
| April | 56°F | 30°F | 43.2°F | 1.34 | 4.6 | 8 | <1 | 18 | 13 h 30 min |
| May | 68°F | 42°F | 55.3°F | 2.50 | 0.4 | 10 | 1 | 4 | 15 h |
| June | 78°F | 53°F | 65.4°F | 3.36 | 0.0 | 12 | 3 | <1 | 15 h 50 min |
| July | 85°F | 58°F | 71.3°F | 3.07 | 0.0 | 10 | 8 | <1 | 15 h 30 min |
| August | 84°F | 56°F | 69.6°F | 2.50 | 0.0 | 8 | 7 | <1 | 14 h 20 min |
| September | 73°F | 46°F | 59.7°F | 1.72 | 0.0 | 7 | 2 | 2 | 12 h 40 min |
| October | 57°F | 33°F | 44.8°F | 1.43 | 2.5 | 7 | <1 | 15 | 11 h |
| November | 41°F | 19°F | 29.9°F | 0.69 | 8.0 | 7 | <1 | 28 | 9 h 30 min |
| December | 28°F | 8°F | 17.9°F | 0.60 | 10.1 | 8 | <1 | 31 | 8 h 30 min |
| Year (annual) | 55°F | 31°F | 43.1°F | 19.05 | 50.5 | 100 | 21 | 184 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −5°C | −16°C | −10.7°C | 12 mm | 23 cm |
| February | −2°C | −14°C | −8.1°C | 13 mm | 19 cm |
| March | 5°C | −7°C | −1.1°C | 21 mm | 22 cm |
| April | 13°C | −1°C | 6.2°C | 34 mm | 12 cm |
| May | 20°C | 6°C | 12.9°C | 64 mm | 1 cm |
| June | 26°C | 12°C | 18.6°C | 85 mm | 0 cm |
| July | 29°C | 14°C | 21.8°C | 78 mm | 0 cm |
| August | 29°C | 13°C | 20.9°C | 64 mm | 0 cm |
| September | 23°C | 8°C | 15.4°C | 44 mm | 0 cm |
| October | 14°C | 0°C | 7.1°C | 36 mm | 6 cm |
| November | 5°C | −7°C | −1.2°C | 18 mm | 20 cm |
| December | −2°C | −13°C | −7.8°C | 15 mm | 26 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00024011; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Bismarck?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, September has the fewest days with rain (7).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00024011.
When is the last frost in Bismarck?
In Bismarck, the last spring frost (32°F) comes after May 14 in half of years and after May 27 in one year in ten; the first autumn frost comes before September 27 in half of years and before September 15 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 141 year in 10 after May 27; 9 in 10 after May 1
- First autumn frost, half of years before
- September 271 year in 10 before September 15; 9 in 10 before October 9
NOAA puts the median frost-free season at 136 days, and the season without a hard freeze (28°F) at 154 days.
A hard freeze (28°F) comes after May 3 in half of springs and before October 5 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Bismarck in zone 4a across its 3 ZIP code areas (4a in 58504, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Bismarck's NOAA station is in zone 4a: the coldest night of a typical year reaches −28°F (30 complete years).
Frost dates for every NOAA station in North Dakota · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00024011; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
What hardiness zone is each Bismarck ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Bismarck's 3 ZIP code areas are all in zone 4a. Each ZIP's frost dates are in the frost tool.
Source: USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; ZIP areas in the place: Census Bureau 2020 ZCTA-to-place relationship file. A ZIP area counts when at least a tenth of its land (and 0.5 km²) lies in the place.
How hot and how cold does it get in Bismarck?
In a normal year in Bismarck, 21 days a year reach 90°F (2 of them 100°F or more), 184 nights fall to 32°F or colder and 100 days bring measurable precipitation.
- Days at 90°F or more
- 21a normal year
- Days at 100°F or more
- 2a normal year
- Nights at 32°F or colder
- 184a normal year
- Days that stay below freezing
- 77high of 32°F or less
- Days with 0.01 inch of precipitation
- 100a normal year
- Days with 1 inch of snow or more
- 14a normal year
The highest temperature in Bismarck's official record (kept by the National Weather Service since 1874) is 114°F, on July 6, 1936; the lowest is −45°F, on January 13, 1916.
The wettest calendar year on that record is 1876, with 30.92 in; the snowiest season is 1996–97, with 101.6 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00024011; records: ACIS (NOAA Regional Climate Centers), NWS threaded record BISthr. Records use complete months only; a month missing more than three days is left out.
How humid and windy is Bismarck, and how clear are its skies?
The summer (June-August) dew point averages 55°F. The muggiest month is July, with an average dew point of 57°F; the driest air comes in December (8°F). March is the windiest month (10.8 mph on average), and August has the most clear or nearly clear hours (77%).
| Month | Dew point | Humidity | Afternoon humidity | Wind | Clear or few clouds | Overcast |
|---|---|---|---|---|---|---|
| January | 10°F | 76% | 66% | 8.8 mph | 54% | 35% |
| February | 13°F | 74% | 61% | 9.5 mph | 51% | 38% |
| March | 25°F | 64% | 43% | 10.8 mph | 57% | 31% |
| April | 34°F | 57% | 38% | 10.7 mph | 56% | 29% |
| May | 48°F | 63% | 44% | 9.7 mph | 58% | 25% |
| June | 56°F | 65% | 45% | 9.1 mph | 69% | 14% |
| July | 57°F | 63% | 41% | 8.1 mph | 76% | 9% |
| August | 53°F | 63% | 40% | 8.7 mph | 77% | 12% |
| September | 39°F | 63% | 40% | 9.3 mph | 69% | 20% |
| October | 27°F | 68% | 48% | 9.6 mph | 57% | 32% |
| November | 16°F | 75% | 61% | 9.0 mph | 53% | 37% |
| December | 8°F | 77% | 69% | 8.7 mph | 52% | 38% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00024011. Monthly averages of all hours; afternoon humidity at 3 p.m. local standard time; sky as the share of hours NOAA's observations rate clear or few clouds (a dash where NOAA publishes no sky value).
How sunny is Bismarck?
Over a year 77% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Bismarck, 4.0 kWh per square metre a day. July is the sunniest month (85%) and December the cloudiest (68%). Among the 459 U.S. places of 50,000 or more, that ranks tied 243rd (with 32 others) in sunshine.
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 78% | 1.8 |
| February | 81% | 2.9 |
| March | 73% | 3.8 |
| April | 73% | 5.0 |
| May | 73% | 5.8 |
| June | 78% | 6.5 |
| July | 85% | 6.8 |
| August | 83% | 5.6 |
| September | 79% | 4.3 |
| October | 71% | 2.7 |
| November | 71% | 1.8 |
| December | 68% | 1.3 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Bismarck need?
A normal year in Bismarck brings 8,471 heating degree days, 58% more than the median U.S. place (5,373), and 536 cooling degree days, 41% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,355 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,618 | 0 |
| February | 1,330 | 0 |
| March | 1,084 | 0 |
| April | 655 | 1 |
| May | 316 | 17 |
| June | 77 | 89 |
| July | 16 | 211 |
| August | 31 | 174 |
| September | 204 | 44 |
| October | 626 | 2 |
| November | 1,055 | 0 |
| December | 1,460 | 0 |
| Year (annual) | 8,471 | 536 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00024011. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Bismarck been warmer than normal lately?
2025 averaged 44.1°F, 1.0°F above the 1991-2020 normal of 43.1°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 47.2°F | +4.1°F | 12.42 | 28.6 |
| 2022 | 42.5°F | −0.6°F | 17.33 | 86.7 |
| 2023 | 43.8°F | +0.7°F | 20.55 | 61.7 |
| 2024 | 46.0°F | +2.9°F | 17.29 | 29.3 |
| 2025 | 44.1°F | +1.0°F | 25.92 | 34.6 |
Over 148 complete years from 1875 to 2025, the station's annual mean temperature rose at a fitted 4.3°F per century (+0.24°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00024011; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Bismarck's climate compare?
Bismarck is warmer than 81 of the other 91 places with their own NOAA record in North Dakota, and wetter than 39. Across the 7,247 U.S. stations with normals, its annual mean of 43.1°F is warmer than 12%.
In the Köppen classification computed from these normals, Bismarck is Dfb: continental, no dry season, warm summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Bismarck share this climate record?
3 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Lincoln, ND4,502 people · 3 mi E
- Apple Valley, ND191 people · 8 mi NE
- Menoken, ND95 people · 11 mi E
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Bismarck's other NOAA stations record?
2 more NOAA stations keep 1991-2020 normals in or near Bismarck. This page uses Bismarck Municipal Airport; the others differ by site and elevation:
| Station | From the center | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Bismarck (2.4 mi NNW) USC00320817 | 2 mi NW | 1,831 ft | 42.3°F | 4°F | 82°F | 20.4 | – | May 10 |
| Bismarck Weather Office USC00320818 | 3 mi S | 1,651 ft | 42.8°F | 3°F | 84°F | 19.2 | – | May 14 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Bismarck's climate
What is the coldest month in Bismarck?
January, with a normal high of 23°F and a normal low of 2°F. The warmest is July (85°F by day, 58°F at night).
Does it snow in Bismarck?
Yes: 51 inches in a normal year, falling on 45 days with 0.1 inch or more, the most in December (10.1 inches).
What is the rainiest month in Bismarck?
June, with 3.36 in of precipitation in a normal year; the driest is January with 0.48 in.
What plant hardiness zone is Bismarck in?
The USDA's 2023 map puts Bismarck in zone 4a across its 3 ZIP code areas (4a in 58504, the largest). By the same method at Bismarck's NOAA station, the coldest night of a typical year reaches −28°F (30 years, 1991-2020): zone 4a.
How late can frost come in Bismarck?
In half of years the last 32°F night comes after May 14; in one year in ten it comes after May 27. Waiting until May 27 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Bismarck in OctoberThis month day by day, its records and recent years
- North Dakota climateThe statewide normals and every place in the state
- Mandan, ND7 miles from this station, 42.4°F a year
- Moffit (3 mi SE), ND26 miles from this station, 43.6°F a year
- Hazelton, ND26 miles from this station, 41.0°F a year
- Wilton, ND27 miles from this station, 40.6°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made