Climate averages 1991–2020
Rapid City weather
in October.
A cool, moderately wet month: the 6th warmest and the 7th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
October is a cool month in Rapid City: daytime highs average 14.9°C and nights cool to about 3.9°C. By daytime temperature it is the 6th warmest of the 12 months.
Expect about 50 mm of rain on roughly 7 days, which makes October a moderately wet month (the 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 11 h 03 min on an average October day.
The nearest other city in this atlas is Bismarck (358 km away). In October its highs average 12.7°C, 2.2°C cooler than Rapid City, with 45 mm of rain.
Among the 498 cities listed in the United States, Rapid City ranks joint 463rd of 498 for the warmest October highs and 166th of 498 for the driest October (rainfall, lowest first). The mean October high of those 498 cities is 21.4°C; Rapid City is 6.4°C cooler than that mean.
From October to November, average highs fall by 7.0°C to 7.9°C, and monthly rainfall falls from 50 mm to 20 mm.
The annual picture
October in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Rapid City climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 2.5°C-8.1°C | -8.1°C | 13 | 3.9 | 9.39 h |
| February | 3.5°C-7.6°C | -7.6°C | 20 | 5.1 | 10.410 h |
| March | 8.5°C-3.5°C | -3.5°C | 40 | 7.6 | 11.912 h |
| April | 12.8°C1.1°C | 1.1°C | 80 | 11.8 | 13.413 h |
| May | 18.4°C7.2°C | 7.2°C | 112 | 14.1 | 14.715 h |
| June | 24.4°C12.9°C | 12.9°C | 97 | 14.5 | 15.415 h |
| July | 28.9°C16.9°C | 16.9°C | 78 | 13.4 | 15.115 h |
| August | 28.2°C16.1°C | 16.1°C | 60 | 10.8 | 14.014 h |
| September | 23.3°C11.2°C | 11.2°C | 42 | 6.7 | 12.613 h |
| October, selected | 14.9°C3.9°C | 3.9°C | 50 | 7.3 | 11.011 h |
| November | 7.9°C-2.5°C | -2.5°C | 20 | 4.4 | 9.710 h |
| December | 2.8°C-6.9°C | -6.9°C | 15 | 3.6 | 9.09 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
October in nearby cities
- Bismarck in OctoberUnited States · 358 kmHigh 12.7°C · Low 3.3°C · 45 mm rain
- Fort Collins in OctoberUnited States · 417 kmHigh 16.3°C · Low 2.9°C · 40 mm rain
- Greeley in OctoberUnited States · 424 kmHigh 17.9°C · Low 3.9°C · 30 mm rain
- Loveland in OctoberUnited States · 437 kmHigh 16.5°C · Low 2.9°C · 40 mm rain
- Billings in OctoberUnited States · 456 kmHigh 15.1°C · Low 3.3°C · 46 mm rain
- Longmont in OctoberUnited States · 462 kmHigh 16.8°C · Low 3.2°C · 41 mm rain
- Boulder in OctoberUnited States · 482 kmHigh 16.5°C · Low 3.1°C · 48 mm rain
- Thornton in OctoberUnited States · 490 kmHigh 16.6°C · Low 2.3°C · 40 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Rapid City) is explained once on the Rapid City year overview and on the Sources, method and limits page.