Rolla, North Dakota climate: Normal weather by month, frost dates and records
Rolla's normal year runs from −3°F January nights to 75°F July afternoons, with 19.6 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 2.5°C, January lows of −20°C, July highs of 24°C, 499 mm of precipitation a year.
- NOAA stationRolla (1 mi NE)
- Station IDUSC00327664
- Location48.88°N 99.59°W
- Elevation1,833 ft (559 m)
- Population1,157
On October 23, the normal high in Rolla is 46°F and the normal low 26°F, and the chance of measurable rain or snow is 19%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Rolla.
- Jan 15° -3°
- Feb 19° 0°
- Mar 30° 12°
- Apr 48° 25°
- May 62° 38°
- Jun 70° 49°
- Jul 75° 54°
- Aug 75° 52°
- Sep 65° 43°
- Oct 50° 29°
- Nov 33° 16°
- Dec 20° 3°
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 Rolla each month?
July is the warmest month, with normal highs of 75°F; January the coldest, with normal lows of −3°F. The most precipitation falls in June (3.73 in), the least in January (0.37 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 15°F | −3°F | 5.9°F | 0.37 | 6 | <1 | 31 | 8 h 40 min |
| February | 19°F | 0°F | 9.3°F | 0.43 | 5 | <1 | 28 | 10 h 10 min |
| March | 30°F | 12°F | 20.8°F | 0.70 | 5 | <1 | 30 | 11 h 50 min |
| April | 48°F | 25°F | 36.3°F | 1.09 | 5 | <1 | 21 | 13 h 40 min |
| May | 62°F | 38°F | 49.9°F | 2.86 | 10 | <1 | 6 | 15 h 10 min |
| June | 70°F | 49°F | 59.8°F | 3.73 | 11 | <1 | <1 | 16 h 10 min |
| July | 75°F | 54°F | 64.4°F | 3.33 | 8 | 1 | <1 | 15 h 50 min |
| August | 75°F | 52°F | 63.2°F | 2.72 | 8 | 1 | <1 | 14 h 30 min |
| September | 65°F | 43°F | 53.8°F | 1.74 | 7 | <1 | 2 | 12 h 40 min |
| October | 50°F | 29°F | 39.7°F | 1.21 | 6 | <1 | 18 | 10 h 50 min |
| November | 33°F | 16°F | 24.1°F | 0.79 | 6 | <1 | 29 | 9 h 10 min |
| December | 20°F | 3°F | 11.3°F | 0.67 | 6 | <1 | 31 | 8 h 20 min |
| Year (annual) | 47°F | 26°F | 36.5°F | 19.64 | 83 | 2 | 194 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −9°C | −20°C | −14.5°C | 9 mm |
| February | −7°C | −18°C | −12.6°C | 11 mm |
| March | −1°C | −11°C | −6.2°C | 18 mm |
| April | 9°C | −4°C | 2.4°C | 28 mm |
| May | 17°C | 3°C | 9.9°C | 73 mm |
| June | 21°C | 10°C | 15.4°C | 95 mm |
| July | 24°C | 12°C | 18.0°C | 85 mm |
| August | 24°C | 11°C | 17.3°C | 69 mm |
| September | 18°C | 6°C | 12.1°C | 44 mm |
| October | 10°C | −1°C | 4.3°C | 31 mm |
| November | 0°C | −9°C | −4.4°C | 20 mm |
| December | −7°C | −16°C | −11.5°C | 17 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Hansboro (14 miles away), gets 38 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00327664; 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 Rolla?
Normal highs sit between 65°F and 85°F in 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 USC00327664.
When is the last frost in Rolla?
In Rolla, the last spring frost (32°F) comes after May 20 in half of years and after May 31 in one year in ten; the first autumn frost comes before September 26 in half of years and before September 14 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 201 year in 10 after May 31; 9 in 10 after May 8
- First autumn frost, half of years before
- September 261 year in 10 before September 14; 9 in 10 before October 8
NOAA puts the median frost-free season at 128 days, and the season without a hard freeze (28°F) at 146 days.
A hard freeze (28°F) comes after May 11 in half of springs and before October 3 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Rolla in zone 3b in ZIP code 58367, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Rolla's NOAA station is in zone 4a: the coldest night of a typical year reaches −29°F (17 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in North Dakota · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00327664; 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.
How hot and how cold does it get in Rolla?
In a normal year in Rolla, 2 days a year reach 90°F, 194 nights fall to 32°F or colder and 83 days bring measurable precipitation.
- Days at 90°F or more
- 2a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 194a normal year
- Days that stay below freezing
- 114high of 32°F or less
- Days with 0.01 inch of precipitation
- 83a normal year
The highest temperature in this station's record (since 1904) is 101°F, on August 7, 1949; the lowest is −43°F, on February 2, 1996.
The wettest calendar year on that record is 1905, with 30.39 in; the snowiest season is 1975–76, with 73.6 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00327664; records: ACIS (NOAA Regional Climate Centers), station USC00327664. Records use complete months only; a month missing more than three days is left out.
How sunny is Rolla?
Over a year 77% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Rolla, 3.9 kWh per square metre a day. February is the sunniest month (89%) and November the cloudiest (67%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 84% | 1.7 |
| February | 89% | 3.0 |
| March | 80% | 4.1 |
| April | 73% | 4.9 |
| May | 72% | 5.7 |
| June | 74% | 6.1 |
| July | 83% | 6.5 |
| August | 80% | 5.3 |
| September | 76% | 3.9 |
| October | 69% | 2.5 |
| November | 67% | 1.5 |
| December | 70% | 1.2 |
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 Rolla need?
A normal year in Rolla brings 10,496 heating degree days, 95% more than the median U.S. place (5,373), and 156 cooling degree days, 83% fewer than the median (908). Nine months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 1,485 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,832 | 0 |
| February | 1,560 | 0 |
| March | 1,372 | 0 |
| April | 863 | 0 |
| May | 472 | 4 |
| June | 185 | 27 |
| July | 83 | 63 |
| August | 108 | 52 |
| September | 344 | 9 |
| October | 785 | 1 |
| November | 1,227 | 0 |
| December | 1,666 | 0 |
| Year (annual) | 10,496 | 156 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00327664. 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.
How does Rolla's climate compare?
Rolla is warmer than 1 of the other 91 places with their own NOAA record in North Dakota, and wetter than 45. Across the 7,247 U.S. stations with normals, its annual mean of 36.5°F is warmer than 2%.
In the Köppen classification computed from these normals, Rolla is Dwb: continental, dry-winter, 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 Rolla share this climate record?
2 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.
- St. John, ND310 people · 7 mi NW
- Perth, ND6 people · 13 mi SE
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Rolla's climate
What is the coldest month in Rolla?
January, with a normal high of 15°F and a normal low of −3°F. The warmest is July (75°F by day, 54°F at night).
Does it snow in Rolla?
Yes. NOAA publishes no 1991-2020 snowfall normal for Rolla's NOAA station; the nearest record that keeps one, Hansboro (14 miles away), records 38 inches of snow in a normal year.
What is the rainiest month in Rolla?
June, with 3.73 in of precipitation in a normal year; the driest is January with 0.37 in.
What plant hardiness zone is Rolla in?
The USDA's 2023 map puts Rolla in zone 3b in ZIP code 58367, the nearest ZIP area. By the same method at Rolla's NOAA station, the coldest night of a typical year reaches −29°F (17 years, 1991-2020): zone 4a.
How late can frost come in Rolla?
In half of years the last 32°F night comes after May 20; in one year in ten it comes after May 31. Waiting until May 31 leaves about a one-in-ten chance of a later frost.
Nearby and next
- North Dakota climateThe statewide normals and every place in the state
- Belcourt, ND8 miles from this station, 38.2°F a year
- Hansboro, ND14 miles from this station, 38.6°F a year
- Rolette, ND20 miles from this station, 36.1°F a year
- Lake Metigoshe State Park, ND35 miles from this station, 37.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made