Climate averages 1991–2020
Rapid City weather
in July.
A hot, moderately wet month: the warmest and the 9th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
July is a hot month in Rapid City: daytime highs average 28.9°C and nights cool to about 16.9°C. By daytime temperature it is the warmest month of the year.
Expect about 78 mm of rain on roughly 13 days, which makes July a moderately wet month (the 9th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 15 h 08 min on an average July day.
The nearest other city in this atlas is Bismarck (358 km away). In July its highs average 27.3°C, 1.6°C cooler than Rapid City, with 77 mm of rain.
Among the 498 cities listed in the United States, Rapid City ranks joint 311th of 498 for the warmest July highs and joint 242nd of 498 for the driest July (rainfall, lowest first). The mean July high of those 498 cities is 30.3°C; Rapid City is 1.4°C cooler than that mean.
From July to August, average highs fall by 0.7°C to 28.2°C, and monthly rainfall falls from 78 mm to 60 mm.
The annual picture
July 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, selected | 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 | 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
July in nearby cities
- Bismarck in JulyUnited States · 358 kmHigh 27.3°C · Low 16.7°C · 77 mm rain
- Fort Collins in JulyUnited States · 417 kmHigh 29.3°C · Low 14.7°C · 44 mm rain
- Greeley in JulyUnited States · 424 kmHigh 31.9°C · Low 17.1°C · 36 mm rain
- Loveland in JulyUnited States · 437 kmHigh 29.2°C · Low 14.7°C · 44 mm rain
- Billings in JulyUnited States · 456 kmHigh 30.7°C · Low 16.6°C · 24 mm rain
- Longmont in JulyUnited States · 462 kmHigh 29.5°C · Low 15.0°C · 42 mm rain
- Boulder in JulyUnited States · 482 kmHigh 28.7°C · Low 14.4°C · 75 mm rain
- Thornton in JulyUnited States · 490 kmHigh 29.2°C · Low 14.5°C · 41 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.