See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
18°
Clear
Feels Like: 19°
Min: 10°
Max: 22°
The next few hours will be clear, with today reaching 22°C and dropping to 10°C. The coming days will be mostly cloudy throughout the day.
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:38
Sunrise
18:56
Sunset
Moon
Waxing Crescent
11:45
Moonrise
20:20
Moonset
Daily Forecast
Today
Wednesday
Thursday
Friday
Saturday
Sunday
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Wednesday
Thursday
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Weather in Rapid City today, September 15, 2026
Conditions in Rapid City on September 15, 2026 favour clear skies, so the day opens with a fine, sunny outlook. Any interruptions to the blue should be brief rather than lasting. Expect a brighter morning, with limited cloud around 0% by 11:00. Conditions start on a settled note.
The day peaks near 22°C and cools toward 10°C. The air stays humid, with relative humidity between 27% and 47% and the peak around 23:00. A lighter breeze peaks around 16:00 near 5.9 km/h.
The afternoon keeps an overcast feel, as cloud reaches about 100% around 15:00. Outdoor plans may still want a flexible backup. Expect visibility around 16.1 km. The sun rises at 06:38 and sets at 18:56, for a total of 12 hours 17 minutes of sunlight today.
In short, September 15, 2026 looks like a fine day in Rapid City for being outside, peaking around 22°C.
Frequently asked questions about weather in Rapid City
How warm does it get in Rapid City?
The warmest month in Rapid City is July, with average high temperatures of 29°C. The average temperature during this period is around 22°C.
How cold does it get in Rapid City?
The coldest month in Rapid City is February, with average low temperatures of -9°C. The average temperature during this period is around -4°C.
What is the wettest time of year in Rapid City?
The wettest month in Rapid City is May, with an average of 102mm of precipitation.
What is the driest time of year in Rapid City?
The driest month in Rapid City is January, with an average of 14mm of precipitation.
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