Williston Sloulin, ND Climate: Temperature & Rain by Month
Average temperature and precipitation from NOAA NCEI 1991–2020 normals →, with a derived climate comfort score
30-year climate normals (1991-2020) from Williston Sloulin's primary NOAA station, WILLISTON SLOULIN INTL AP.
The climate verdict for Williston Sloulin
Winter sets the terms in Williston Sloulin, North Dakota. A pronounced 58.8°F seasonal swing and heating demand above twice the cooling total frame an annual average of 42°F. At 39/100 (below average) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 4% of scores.
- 42°F
- average temperature, NOAA 1991-2020 normal
- 39/100
- comfort score, above 4% of station-mapped location scores
- 15.1"
- annual precipitation · 48" snow
- 123 days
- growing season, frost-free days
Williston Sloulin: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USW00094014 · Williston Sloulin, ND 42°F mean · 15.1" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-WIDE · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 42°F
- RANK-COOL #617
- PHOTO-FINISH ≈ Rothsay
- PRCP-DRY 15.1"
- SWING-WIDE 59°F
- COMF-LOW 39/100
- LOAD-HEAT 8,906 HDD
- STN-1 USW00094014
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Rothsay, MN (+ 0 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every ND station list.
- Williston Sloul… (this station) 42°F
- Cold New Salem, ND 42°F
- Hot Eureka, SD 42°F
- Near Rothsay, MN 42°F
- Near Steele, ND 42°F
Williston Sloulin sits in North Dakota, the #2 coldest U.S. state at 41.0°F statewide annual average - see all 50 coldest states ranked by NOAA normals
Climate Living Index · Williston Sloulin
Williston Sloulin: 28/100 · grade F
Williston Sloulin publishes all six Living Index dimensions from NOAA annual/seasonal normals · NOAA daily multivariate normals · NOAA hourly normals.
PlainClimate-derived for Williston Sloulin, not an official NOAA rating. Rankings still use Comfort Score 39/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Summer moisture balance | 51.8°F mean dew point | 96/100 · A |
| Precipitation balance | 15.1 in · 19.9 from 35 in | 29/100 · F |
| Snowfall burden | 48.2 inches/year | 22/100 · F |
| Normal heat + freeze calendar | 195 calendar days | 17/100 · F |
| Annual temperature balance | 41.7°F · 25.8° from 67.5°F | 9/100 · F |
| Frost-free season | 123 days/year | 8/100 · F |
Williston Sloulin · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Williston Sloulin's normals sit in a dry climate class: BSk
Precipitation is low relative to temperature but above true desert thresholds: cold semi-arid steppe (BSk). Class BSk is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: dry (arid or semi-arid), specifically cold semi-arid steppe.
- Köppen code
- BSk
- Group
- Dry (arid or semi-arid)
- Warmest month
- 70.4°F
- Coldest month
- 11.6°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where Williston Sloulin sits across the climate record
Three NOAA fields for Williston Sloulin's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 91%
- Among 6,861 stations, Williston Sloulin sits in the cooler third of annual means.
- Annual precipitation
- Drier than 82%
- Williston Sloulin's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- Wider than 97%
- Warmest-to-coldest month gap for Williston Sloulin is large versus 6,861 complete station-years.
How Williston Sloulin compares across U.S. station-mapped locations
Williston Sloulin's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
39 4th percentile score exceeds 4% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). This entry sits in this band.
- 40–50: 1,113 station-mapped locations (18%). Above this entry.
- 50–60: 1,329 station-mapped locations (21%). Above this entry.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 70–80: 650 station-mapped locations (11%). Above this entry.
- 80–90: 921 station-mapped locations (15%). Above this entry.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Williston Sloulin's measured station temperature trend
MethodologyAcross 134 complete annual observations from 1879 to 2018, WILLISTON SLOULIN INTL AP warmed at a fitted rate of 0.17°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Williston Sloulin primary station fitted change +0.17 °C/decade
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 22°F (-5°C) | 1°F (-17°C) | 12°F (-11°C) | 0.6" | 11.2" | 30.8 | 0.0 |
| February | 27°F (-3°C) | 6°F (-15°C) | 16°F (-9°C) | 0.5" | 6.7" | 27.7 | 0.0 |
| March | 40°F (5°C) | 18°F (-8°C) | 29°F (-2°C) | 0.6" | 6.4" | 28.6 | 0.0 |
| April | 56°F (13°C) | 29°F (-2°C) | 42°F (6°C) | 1.1" | 3.7" | 18.7 | 0.1 |
| May | 67°F (20°C) | 40°F (5°C) | 54°F (12°C) | 2.1" | 0.9" | 6.1 | 0.3 |
| June | 77°F (25°C) | 50°F (10°C) | 64°F (18°C) | 2.6" | 0.0" | 0.3 | 2.1 |
| July | 85°F (29°C) | 56°F (13°C) | 70°F (21°C) | 2.5" | 0.0" | 0.0 | 8.2 |
| August | 84°F (29°C) | 54°F (12°C) | 69°F (21°C) | 1.6" | 0.0" | 0.0 | 8.5 |
| September | 73°F (23°C) | 44°F (6°C) | 58°F (14°C) | 1.4" | 0.0" | 2.7 | 2.1 |
| October | 56°F (13°C) | 30°F (-1°C) | 43°F (6°C) | 0.9" | 2.6" | 17.0 | 0.1 |
| November | 38°F (4°C) | 17°F (-8°C) | 28°F (-2°C) | 0.7" | 6.3" | 28.4 | 0.0 |
| December | 26°F (-3°C) | 6°F (-14°C) | 16°F (-9°C) | 0.6" | 10.4" | 30.9 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 87°F around July 30, short of 90°F on every date, while 195 dates carry a normal low at or below freezing, the coldest 1°F near January 13.
The freezing stretch
The normal low stays at or below 32°F into April 24, then returns to freezing around October 13, covering 195 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is June 12, when 41% of years recorded at least a hundredth of an inch. The driest is October 19 at 22%. Summed across the calendar, that is about 100 wet dates a year.
The widest day
August 25 carries the biggest normal gap between afternoon and dawn, 30°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Williston Sloulin.
Where Williston Sloulin Stands Nationally
Freezing is routine here by normals standards — the normal low reaches 32°F or colder on about 195 nights a year, more than most ranked stations.
A drier-than-most normal water year — around 15 inches, below what four out of five ranked stations collect.
Williston Sloulin earns 2 nationally notable standings (outer quintiles) against 6,860 NOAA 1991–2020 normals stations; only those extremes render.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 11.2"
7.6 days with precipitation
Snow: 6.7"
7.1 days with precipitation
Snow: 6.4"
7.4 days with precipitation
Snow: 3.7"
8.3 days with precipitation
Snow: 0.9"
9.9 days with precipitation
12.3 days with precipitation
9.2 days with precipitation
8.7 days with precipitation
7.5 days with precipitation
Snow: 2.6"
6.9 days with precipitation
Snow: 6.3"
6.8 days with precipitation
Snow: 10.4"
8.5 days with precipitation
Williston Sloulin runs a summer-peaked wet season
44% of Williston Sloulin's yearly precipitation falls in June, July and August alone, against the 25% an evenly spread year would give those three months. The wettest month is June at 2.6", on a wide 58.8°F gap between its warmest and coldest month. Warm-season convection and, across the Southwest, the North American monsoon produce this shape: rain arrives in short heavy bursts during the hottest part of the year rather than as long cool-season soaking.
- Wettest three months: June, July, May, taking 48% of the annual total between them.
- Driest month: February at 0.5".
- Winter share: 11% falls in December, January and February.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. A summer-peaked label means the June-August share reaches 35%; it describes timing across an average year, not any single season, and says nothing about how heavy an individual storm can be.
Williston Sloulin is dry, and what does fall arrives gently
Only about 100 days a year record measurable precipitation here, 27% of the calendar, and they carry 15.1" between them. At roughly 0.15 inches on an average wet day, this is not the damp drizzle of a marine climate; it is an arid record in which precipitation is both uncommon and light when it appears.
The wettest month by count is June at about 12 wet days; the driest is November at about 7.
A low per-event average in a dry record is a statement about typical days only. Arid regions can still take a large share of a year's total from a single convective storm, which a normal cannot show.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, not the extremes within it.
Winter brings real snow to Williston Sloulin
Williston Sloulin averages 48.2 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 43 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 48.2 inches of depth.
- Days recording measurable snow: about 43 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 32% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
September 21
50% probability date
Last Spring Freeze
May 21
50% probability date
Growing Season
123 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
8,906
Higher = more heating needed
Cooling Degree Days
457
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Humidity & Wind
Monthly averages from hourly observations
| Month | Humidity | Wind (mph) | Clear Sky % | Overcast % |
|---|---|---|---|---|
| January | 78% | 8.3 | 50% | 32% |
| February | 76% | 8.7 | 45% | 36% |
| March | 63% | 9.9 | 49% | 29% |
| April | 56% | 10.5 | 47% | 27% |
| May | 61% | 9.7 | 47% | 25% |
| June | 62% | 8.8 | 60% | 13% |
| July | 58% | 7.9 | 69% | 8% |
| August | 57% | 8.2 | 68% | 12% |
| September | 61% | 8.6 | 64% | 18% |
| October | 69% | 9.3 | 52% | 32% |
| November | 77% | 8.2 | 48% | 37% |
| December | 78% | 8.2 | 49% | 36% |
Nationwide similar cities
Other rankable U.S. places outside ND closest to Williston Sloulin on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (42°F here).
- Bayfield, WI 42°F · 0.0°F off
- Castlewood, SD 42°F · 0.0°F off
- Chemult, OR 42°F · 0.0°F off
- Eagle Nest, NM 42°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (15.1" here), excluding temperature-peer places.
- Darby, MT 15.1" · 0.0" off
- Highwood, MT 15.1" · 0.0" off
- Bly, OR 15.1" · 0.0" off
- Guernsey, WY 15.1" · 0.0" off
Snow and freeze rhythm
When cold and snow define Williston Sloulin
heating led · dry · high swing
Winter and seasonal range jointly define this record. Williston Sloulin logs 8,906 heating degree days, more than twice its 457 cooling total, while the typical coldest-to-warmest-month gap reaches 58.8°F. The annual mean therefore compresses two materially different seasons.
Only about 123 days are frost-free in a normal year. That short interval is consistent with the cold-season signal, but the measure does not predict the exact first or last freeze in any one year.
-
1. Williston Sloulin coldest normal
January
Averaging 12°F (-11°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Williston Sloulin typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Williston Sloulin snow peak
January
Williston Sloulin averages 48.2 inches of snow a year, with January the snowiest month on the normals.
Questions about Williston Sloulin's climate
How much snow does Williston Sloulin get? ▼
How cold does Williston Sloulin get in winter? ▼
How much energy does heating and cooling require in Williston Sloulin? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Williston Sloulin's primary station: WILLISTON SLOULIN INTL AP (USW00094014). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The conservative exact name-and-state crosswalk finds no Census place match, so PlainClimate treats this as a station-mapped location and does not claim it is a municipality. No exact Gazetteer row for Williston Sloulin; facility counts that depend on place identity are therefore an upper bound, not a municipal census.
On this page every temperature, precipitation, and derived score for Williston Sloulin comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.