Rapid City, 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 Rapid City's primary NOAA station, RAPID CITY 4NW - 2 stations mapped to the area.
The climate verdict for Rapid City
Dryness leads the climate profile for Rapid City, South Dakota, with 18.8 inches of precipitation a year. NOAA records an annual average of 46°F. At 49/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 18% of scores.
- 46°F
- annual average temperature (NOAA normal)
- 49/100
- comfort score, above 18% of station-mapped location scores
- 18.8"
- annual precipitation · 36" snow
- 148 days
- frost-free growing season
Rapid City: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00396947 · Rapid City, SD 46°F mean · 18.8" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-WIDE · COMF-LOW · LOAD-HEAT · STN-MULTI · BOOK-FULL
- TEMP-COOL 46°F
- RANK-COOL #1,647
- PHOTO-FINISH ≈ West Bend
- PRCP-DRY 18.8"
- SWING-WIDE 46°F
- COMF-LOW 49/100
- LOAD-HEAT 7,285 HDD
- STN-MULTI USC00396947
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: West Bend, WI (+ 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.
- Rapid City (this station) 46°F
- Cold Peru, NY 46°F
- Hot Lewiston, ME 46°F
- Near West Bend, WI 46°F
- Near Pathfinder Dam, WY 46°F
Climate Living Index · Rapid City
Rapid City: 28/100 · grade F
Rapid City publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Rapid City, not an official NOAA rating. Rankings still use Comfort Score 49/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 18.8 in · 16.2 from 35 in | 43/100 · D |
| Snowfall burden | 36.1 inches/year | 32/100 · F |
| Annual temperature balance | 46.3°F · 21.2° from 67.5°F | 24/100 · F |
| Frost-free season | 148 days/year | 24/100 · F |
| Normal heat + freeze calendar | 181 calendar days | 24/100 · F |
Rapid City · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Rapid City is a continental Köppen climate: Dwb
Coldest-month mean 25.1°F and warmest-month mean 70.9°F place this station in continental, dry-winter, warm summer climates (Dwb). Class Dwb is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, dry-winter, warm summer.
- Köppen code
- Dwb
- Group
- Continental
- Warmest month
- 70.9°F
- Coldest month
- 25.1°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 Rapid City sits across the climate record
Three NOAA fields for Rapid City's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 76%
- Among 6,861 stations, Rapid City sits in the cooler third of annual means.
- Annual precipitation
- Drier than 74%
- Rapid City's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- 63rd percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How Rapid City compares across U.S. station-mapped locations
Rapid City's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
49 18th percentile score exceeds 18% 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%). This entry sits in this band.
- 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
Rapid City's measured station temperature trend
MethodologyAcross 101 complete annual observations from 1888 to 2025, RAPID CITY 4NW warmed at a fitted rate of 0.06°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Rapid City primary station fitted change +0.06 °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 | 37°F (3°C) | 13°F (-10°C) | 25°F (-4°C) | 0.2" | 3.9" | 29.7 | 0.0 |
| February | 38°F (3°C) | 15°F (-10°C) | 26°F (-3°C) | 0.4" | 6.1" | 26.3 | 0.0 |
| March | 47°F (8°C) | 23°F (-5°C) | 35°F (1°C) | 0.9" | 6.2" | 26.7 | 0.0 |
| April | 54°F (12°C) | 31°F (-1°C) | 43°F (6°C) | 2.0" | 7.9" | 16.4 | 0.0 |
| May | 64°F (18°C) | 42°F (5°C) | 53°F (12°C) | 3.7" | 0.9" | 4.2 | 0.3 |
| June | 75°F (24°C) | 52°F (11°C) | 64°F (18°C) | 3.0" | 0.0" | 0.0 | 2.1 |
| July | 84°F (29°C) | 58°F (15°C) | 71°F (22°C) | 2.7" | 0.0" | 0.0 | 7.9 |
| August | 83°F (28°C) | 56°F (13°C) | 70°F (21°C) | 2.0" | 0.0" | 0.0 | 7.1 |
| September | 74°F (23°C) | 47°F (8°C) | 60°F (16°C) | 1.5" | 0.0" | 1.0 | 2.5 |
| October | 59°F (15°C) | 35°F (2°C) | 47°F (8°C) | 1.6" | 2.1" | 10.9 | 0.0 |
| November | 47°F (8°C) | 24°F (-5°C) | 35°F (2°C) | 0.5" | 4.0" | 24.8 | 0.0 |
| December | 39°F (4°C) | 15°F (-9°C) | 27°F (-3°C) | 0.3" | 5.0" | 30.0 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 85°F around July 25, short of 90°F on every date, while 181 dates carry a normal low at or below freezing, the coldest 13°F near January 20.
The freezing stretch
The normal low stays at or below 32°F into April 20, then returns to freezing around October 23, covering 181 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 3, when 36% of years recorded at least a hundredth of an inch. The driest is December 10 at 8%. Summed across the calendar, that is about 68 wet dates a year.
The widest day
September 4 carries the biggest normal gap between afternoon and dawn, 28°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Rapid City.
Where Rapid City Stands Nationally
Freezing is routine here by normals standards — the normal low reaches 32°F or colder on about 181 nights a year, more than most ranked stations.
Rapid City earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 3.9"
2.9 days with precipitation
Snow: 6.1"
3.5 days with precipitation
Snow: 6.2"
4.1 days with precipitation
Snow: 7.9"
7.4 days with precipitation
Snow: 0.9"
9.0 days with precipitation
10.4 days with precipitation
8.7 days with precipitation
5.9 days with precipitation
4.6 days with precipitation
Snow: 2.1"
5.2 days with precipitation
Snow: 4.0"
3.1 days with precipitation
Snow: 5.0"
2.4 days with precipitation
Rapid City runs a summer-peaked wet season
40% of Rapid City'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 wide 45.8°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: May, June, July, taking 50% of the annual total between them.
- Driest month: January at 0.2".
- Winter share: 5% 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 Rapid City's precipitation splits across the calendar
About 67 days a year record measurable precipitation here, carrying 18.8" between them, or roughly 0.28 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 Rapid City
Rapid City averages 36.1 inches of snowfall a year, with April the snowiest month on the normals, spread across roughly 17 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: 36.1 inches of depth.
- Days recording measurable snow: about 17 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 19% 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 5
50% probability date
Last Spring Freeze
May 10
50% probability date
Growing Season
148 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
7,285
Higher = more heating needed
Cooling Degree Days
495
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside SD closest to Rapid City 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 (46°F here).
- Binghamton, NY 46°F · 0.0°F off
- Chewelah, WA 46°F · 0.0°F off
- Delanson, NY 46°F · 0.0°F off
- Douglas, WY 46°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (18.8" here), excluding temperature-peer places.
- Kenai, AK 18.8" · 0.0" off
- Dayton, WA 18.8" · 0.0" off
- Upham, ND 18.8" · 0.0" off
- Lakin, KS 18.8" · 0.0" off
Snow and freeze rhythm
When cold and snow define Rapid City
heating led · dry · mid swing
Rapid City's energy balance leans toward cold weather: 7,285 annual heating degree days against 495 for cooling. Its 45.8°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 148 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. Rapid City coldest normal
January
Averaging 25°F (-4°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Rapid City typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Rapid City snow peak
April
Rapid City averages 36.1 inches of snow a year, with April the snowiest month on the normals.
Questions about Rapid City's climate
How much snow does Rapid City get? ▼
How cold does Rapid City get in winter? ▼
How much energy does heating and cooling require in Rapid City? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Rapid City's primary station: RAPID CITY 4NW (USC00396947). 2 NOAA stations are mapped to the Rapid City area; the primary station's record is used for consistency. 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 4652980). Match rule for Rapid City: 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 Rapid City 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.