Spearfish, SD Climate: Temperature & Rain by Month
Annual temperature and rainfall from NOAA NCEI's 1991–2020 normals →; comfort score computed by PlainClimate
30-year climate normals (1991-2020) from Spearfish's primary NOAA station, SPEARFISH.
The climate verdict for Spearfish
Spearfish, South Dakota has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 47°F. At 54/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 31% of scores.
- 47°F
- annual average temperature (NOAA normal)
- 54/100
- comfort score, above 31% of station-mapped location scores
- 21.4"
- annual precipitation · 71" snow
- 143 days
- frost-free days per growing season
Spearfish: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00397882 · Spearfish, SD 47°F mean · 21.4" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-MID · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 47°F
- RANK-COOL #1,715
- PHOTO-FINISH ≈ Roundup
- PRCP-DRY 21.4"
- SWING-MID 45°F
- COMF-LOW 54/100
- LOAD-HEAT 7,218 HDD
- STN-1 USC00397882
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Roundup, MT (+ 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 SD station list.
- Spearfish (this station) 47°F
- Hot Rock Springs, WI 47°F
- Near Roundup, MT 47°F
- Cold Bad Axe, MI 46°F
- Near Sandusky, MI 46°F
Climate Living Index · Spearfish
Spearfish: 29/100 · grade F
Spearfish publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Spearfish, not an official NOAA rating. Rankings still use Comfort Score 54/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 21.4 in · 13.6 from 35 in | 52/100 · D |
| Normal heat + freeze calendar | 174 calendar days | 29/100 · F |
| Annual temperature balance | 46.5°F · 21.0° from 67.5°F | 25/100 · F |
| Frost-free season | 143 days/year | 20/100 · F |
| Snowfall burden | 70.5 inches/year | 10/100 · F |
Spearfish · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Spearfish is a continental Köppen climate: Dfb
Coldest-month mean 25.8°F and warmest-month mean 70.6°F place this station in continental, no dry season, warm summer climates (Dfb). Class Dfb is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, no dry season, warm summer.
- Köppen code
- Dfb
- Group
- Continental
- Warmest month
- 70.6°F
- Coldest month
- 25.8°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 Spearfish sits across the climate record
Three NOAA fields for Spearfish's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 75%
- Among 6,861 stations, Spearfish sits in the cooler third of annual means.
- Annual precipitation
- Drier than 70%
- Spearfish's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- 57th percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How Spearfish compares across U.S. station-mapped locations
Spearfish's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
54 31st percentile score exceeds 31% 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%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). Below this entry.
- 50–60: 1,329 station-mapped locations (21%). This entry sits in this band.
- 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
Spearfish's measured station temperature trend
MethodologyAcross 59 complete annual observations from 1893 to 2025, SPEARFISH changed little at a fitted rate of 0.01°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Spearfish primary station fitted change +0.01 °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 | 36°F (2°C) | 16°F (-9°C) | 26°F (-3°C) | 0.6" | 8.2" | 26.4 | 0.0 |
| February | 37°F (3°C) | 16°F (-9°C) | 27°F (-3°C) | 0.9" | 12.7" | 24.3 | 0.0 |
| March | 46°F (8°C) | 24°F (-4°C) | 35°F (2°C) | 1.2" | 12.0" | 21.7 | 0.0 |
| April | 55°F (13°C) | 32°F (0°C) | 44°F (6°C) | 2.2" | 8.5" | 12.8 | 0.0 |
| May | 64°F (18°C) | 42°F (5°C) | 53°F (12°C) | 3.7" | 2.3" | 2.3 | 0.3 |
| June | 75°F (24°C) | 51°F (11°C) | 63°F (17°C) | 3.5" | 0.0" | 0.0 | 2.7 |
| July | 84°F (29°C) | 58°F (14°C) | 71°F (21°C) | 2.4" | 0.0" | 0.0 | 11.0 |
| August | 83°F (28°C) | 56°F (13°C) | 70°F (21°C) | 1.9" | 0.0" | 0.0 | 8.5 |
| September | 74°F (23°C) | 48°F (9°C) | 61°F (16°C) | 1.6" | 0.1" | 0.5 | 3.1 |
| October | 58°F (15°C) | 35°F (2°C) | 47°F (8°C) | 2.0" | 5.5" | 9.0 | 0.1 |
| November | 46°F (8°C) | 26°F (-4°C) | 36°F (2°C) | 0.7" | 6.3" | 19.9 | 0.0 |
| December | 37°F (3°C) | 18°F (-8°C) | 27°F (-3°C) | 0.7" | 14.9" | 26.6 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 85°F around July 24, short of 90°F on every date, while 174 dates carry a normal low at or below freezing, the coldest 15°F near February 4.
The freezing stretch
The normal low stays at or below 32°F into April 16, then returns to freezing around October 26, covering 174 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 1, when 42% of years recorded at least a hundredth of an inch. The driest is December 9 at 16%. Summed across the calendar, that is about 94 wet dates a year.
The widest day
August 26 carries the biggest normal gap between afternoon and dawn, 27°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Spearfish.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 8.2"
6.7 days with precipitation
Snow: 12.7"
6.8 days with precipitation
Snow: 12.0"
6.4 days with precipitation
Snow: 8.5"
9.0 days with precipitation
Snow: 2.3"
11.8 days with precipitation
12.3 days with precipitation
9.4 days with precipitation
7.1 days with precipitation
Snow: 0.1"
5.9 days with precipitation
Snow: 5.5"
7.1 days with precipitation
Snow: 6.3"
5.2 days with precipitation
Snow: 14.9"
5.0 days with precipitation
Spearfish runs a summer-peaked wet season
36% of Spearfish'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 May at 3.7", on a 44.8°F seasonal spread. 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: May, June, July, taking 45% of the annual total between them.
- Driest month: January at 0.6".
- Winter share: 10% 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.
How Spearfish's precipitation splits across the calendar
About 93 days a year record measurable precipitation here, carrying 21.4" between them, or roughly 0.23 inches on a typical wet day. That sits in the middle band: neither the many-light-days pattern of the Pacific Northwest and the Great Lakes, nor the few-heavy-events pattern of the Gulf and the desert Southwest.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year and say nothing about the heaviest single storm on record.
Winter brings real snow to Spearfish
Spearfish averages 70.5 inches of snowfall a year, with December the snowiest month on the normals, spread across roughly 24 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: 70.5 inches of depth.
- Days recording measurable snow: about 24 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 33% 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
October 2
50% probability date
Last Spring Freeze
May 12
50% probability date
Growing Season
143 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
7,218
Higher = more heating needed
Cooling Degree Days
506
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside SD closest to Spearfish 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 (47°F here).
- Beulah, MI 47°F · 0.0°F off
- Charles City, IA 47°F · 0.0°F off
- Coggon, IA 47°F · 0.0°F off
- Fort Dodge, IA 47°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (21.4" here), excluding temperature-peer places.
- Gage, OK 21.4" · 0.0" off
- Bigfork, MT 21.4" · 0.0" off
- Cambridge, ID 21.4" · 0.0" off
- Orland, CA 21.4" · 0.0" off
Snow and freeze rhythm
When cold and snow define Spearfish
heating led · moderate · mid swing
Spearfish's energy balance leans toward cold weather: 7,218 annual heating degree days against 506 for cooling. Its 44.8°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 143 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. Spearfish coldest normal
January
The monthly mean of 26°F (-3°C) sits near freezing, so cold nights and above-freezing afternoons share the same month.
-
2. Spearfish typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Spearfish snow peak
December
Spearfish averages 70.5 inches of snow a year, with December the snowiest month on the normals.
Questions about Spearfish's climate
How much snow does Spearfish get? ▼
How cold does Spearfish get in winter? ▼
How much energy does heating and cooling require in Spearfish? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Spearfish's primary station: SPEARFISH (USC00397882). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The 2024 Census Gazetteer identifies the exact name-and-state match as an incorporated place (GEOID 4660020). Match rule for Spearfish: exact normalized name + state only, no fuzzy expansion, so nearby differently spelled facilities stay unmatched.
On this page every temperature, precipitation, and derived score for Spearfish 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.