North Dakota

Nelson County, North Dakota Climate

NOAA 1991-2020 normals for Petersburg 2 N, 18.5 km from Nelson County

The warmest month is July, with an average high of 79°F; the coldest is January, with an average low of -4°F. A normal year brings 20.2 in of precipitation and 42.5 in of snow.

Temperature through the year

The normal daily high and low and the record for every date at Rands (S32), since 1903. The line marks today.

Normal daily high and low temperature at Nelson County through the year, in °F, with the record for each date.-50050100150JanFebMarAprMayJunJulAugSepOctNovDec
  • Normal low
  • Normal high
  • Record high
  • Record low

Normals for Sep 24

Normal high
65°F
Normal low
42°F
Record high
88°Fin 1958
Record low
20°Fin 1942
Chance of a wet day
21%
Daylight
12 h 04 min

Month by month

Averages for 1991-2020. Wet days have at least 0.01 inch of precipitation. Freeze nights have a low of 32°F or colder; degree days are on a 65°F base. Each month links to its own page.

MonthAvg highAvg lowRecord highRecord lowPrecipitationWet daysSnowfallFreeze nightsHeating DDCooling DD
January14°F-4°F54°F (1944)-41°F (1937)0.44 in3.56.3 in31.01,8680
February19°F-1°F62°F (1958)-47°F (1936)0.45 in3.67.7 in28.01,5690
March31°F13°F80°F (1946)-36°F (1948)0.50 in3.47.7 in29.91,3250
April50°F28°F98°F (1980)-9°F (1979)0.94 in4.62.2 in19.87790
May65°F42°F98°F (1964)13°F (1946)2.79 in8.80.6 in5.437213
June74°F53°F106°F (1936)26°F (1935)3.84 in9.80.0 in0.010667
July79°F58°F118°F (1936)34°F (1945)3.61 in8.70.0 in0.035135
August78°F55°F108°F (1947)30°F (1907)2.51 in7.40.0 in0.055104
September69°F45°F103°F (1978)17°F (1939)2.12 in6.50.0 in1.926324
October52°F32°F92°F (1963)-2°F (1936)1.66 in6.52.2 in16.67141
November34°F17°F76°F (1999)-31°F (1985)0.73 in4.04.9 in28.61,1840
December20°F4°F65°F (1939)-35°F (1983)0.64 in3.910.9 in31.01,6510
Year49°F28°F20.23 in7142.5 in1929,920344

Precipitation

Rain and melted snow together. The chance of a wet day is the share of days with at least 0.01 inch of precipitation.

20.2 in in a normal year, most in June.

Chance of a wet day

The chance of at least 0.01 inch of precipitation on each date at Nelson County, in percent, and of at least 0.1 inch of snowfall.010203040JanFebMarAprMayJunJulAugSepOctNovDec
  • Chance of a wet day
  • Chance of snowfall

Snow

NOAA 1991-2020 snowfall normals for Petersburg 2 N.

42.5 in of snow in a normal year.

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Petersburg 2 N. A median date has an even chance of a later freeze in spring, or an earlier one in fall.

The last spring freeze typically comes around May 11 and the first fall freeze around September 28, a growing season of about 138 days.

Median at 36°F
last May 21, first September 20
Median at 32°F
last May 11, first September 28
Median at 28°F
last May 2, first October 7

Frost dates, growing season and degree days

Humidity and comfort

NASA POWER reanalysis, 1991-2020, for the grid cell around Nelson County.

The muggiest month is July, when 7 percent of days are muggy or worse, with a mean dew point of 65°F or more.

MonthDew pointHumidityDryComfortableHumidMuggyOppressiveMiserable
January4°F92%100%0%0%0%0%0%
February9°F87%100%0%0%0%0%0%
March20°F75%100%0%0%0%0%0%
April28°F63%100%0%0%0%0%0%
May40°F63%93%5%1%0%0%0%
June52°F66%68%21%7%4%0%0%
July56°F63%48%28%16%6%1%0%
August53°F61%62%23%11%3%0%0%
September44°F64%89%8%3%1%0%0%
October33°F71%99%0%0%0%0%0%
November21°F80%100%0%0%0%0%0%
December10°F89%100%0%0%0%0%0%

Comfort is judged by the day's mean dew point: dry below 55°F, comfortable to 60°F, humid to 65°F, muggy to 70°F, oppressive to 75°F, miserable above.

Clouds

Average share of the sky covered, from satellite (CERES and GEWEX SRB) by way of NASA POWER, 1991-2020.

The clearest month is August, with the sky 51 percent covered on average; the cloudiest is November, at 67 percent.

Wind

The mean wind speed over the whole day, from the MERRA-2 reanalysis by way of NASA POWER. Gusts run well above it.

The windiest month is March, averaging 12.8 mph at 10 meters (33 feet) above the ground.

Daylight and sunshine

The longest day is Jun 20, with 16 h 03 min of daylight; the shortest is Dec 18, with 8 h 23 min.

Hours of daylight at Nelson County through the year.0510152025JanFebMarAprMayJunJulAugSepOctNovDec
  • Day length

Solar energy

Average daily sunshine reaching the ground on a flat surface, in kilowatt-hours per square meter, clouds included.

Sunrise and sunset calendar

How Nelson County is running

NOAA NCEI Climate at a Glance, from the nClimGrid analysis of every station, updated early each month. A rank of 1 is the highest or lowest of all years since 1895.

August 2026 in Nelson County: 65.3°F (-0.8 °F against 1991-2020), the 55th coolest in 132 years on record.

August 2026 in Nelson County: 1.46 in (-1.17 in against 1991-2020), the 29th driest in 132 years on record.

January to August 2026 in Nelson County: 42.9°F (+1.6 °F against 1991-2020), the 22nd warmest in 132 years on record.

January to August 2026 in Nelson County: 12.13 in (-3.54 in against 1991-2020), the 36th driest in 132 years on record.

Warmest August
72.7°F in 1983
Coolest August
59.0°F in 1977
Wettest August
7.35 in in 1944
Driest August
0.53 in in 1967

Every year since 1895

Each year's average temperature in Nelson County against the 1991-2020 average, in °F, 1895 to 2025.-7.5-5-2.50+2.5+5+7.51900192019401960198020002020NOAA NCEI Climate at a Glance

North Dakota climate and rankings

Month pages

The weather in Nelson County in each month, day by day.

What this means

A normal is the average of the thirty years 1991 to 2020, the period the World Meteorological Organization and NOAA use for comparison. It is an average, not a forecast: most days depart from it, and some by a long way.

A record is the highest or lowest value on the date in every year the station has reported, back to 1903. It rests on one station, so a neighbor a few miles away can hold different ones.

Cloud, humidity, wind and sunshine come from a reanalysis: a weather model run over the past with every observation fed in, averaged over a grid cell about 50 km across. It is consistent everywhere on Earth; it smooths local detail such as a lake shore or a valley.

More for this place

Nearby

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00327027 (Petersburg 2 N), public domain. Records: NOAA GHCN-Daily, station USC00321766, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus. Rankings: NOAA NCEI Climate at a Glance, public domain.