Rapid City weather by month
What a typical year looks like in Rapid City, South Dakota: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Rapid City Regional Airport, 13 km from Rapid City; records cover 1942–2026.
The year at a glance
- Precipitation a year
- 17.4 in443 mm
- Snow a year
- 49 in123 cm
- Last spring freeze
- May 14
- First fall freeze
- Sep 24
- Heating degree days
- 7,252
- Cooling degree days
- 607
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −12°−24° (heating, 99%) and 100°38° (cooling, 1%).
Month by month
Rapid City in January
Highs average 36°2° and lows 13°−11°, with 0.31 in7.9 mm of precipitation and 5 in13 cm of snow in a typical January.
- Record high
- 76°24° (1987)
- Record low
- −27°−33° (1943)
- Heating degree days
- 1260
- Cooling degree days
- 0
Rapid City in February
Highs average 38°3° and lows 14°−10°, with 0.5 in13 mm of precipitation and 8 in20 cm of snow in a typical February.
- Record high
- 75°24° (1988)
- Record low
- −31°−35° (1996)
- Heating degree days
- 1090
- Cooling degree days
- 0
Rapid City in March
Highs average 48°9° and lows 23°−5°, with 0.91 in23 mm of precipitation and 8 in21 cm of snow in a typical March.
- Record high
- 87°31° (2026)
- Record low
- −21°−29° (1996)
- Heating degree days
- 918
- Cooling degree days
- 0
Rapid City in April
Highs average 57°14° and lows 31°0°, with 2.1 in53 mm of precipitation and 10 in26 cm of snow in a typical April.
- Record high
- 93°34° (1989)
- Record low
- −1°−18° (2020)
- Heating degree days
- 634
- Cooling degree days
- 1
Rapid City in May
Highs average 67°19° and lows 42°5°, with 3.5 in88 mm of precipitation and 1.5 in3.8 cm of snow in a typical May.
- Record high
- 98°37° (1969)
- Record low
- 18°−8° (1950)
- Heating degree days
- 349
- Cooling degree days
- 11
Rapid City in June
Highs average 78°25° and lows 52°11°, with 2.9 in73 mm of precipitation in a typical June.
- Record high
- 109°43° (2002)
- Record low
- 31°−1° (1951)
- Heating degree days
- 93
- Cooling degree days
- 81
Rapid City in July
Highs average 86°30° and lows 59°15°, with 2.3 in58 mm of precipitation in a typical July.
- Record high
- 112°44° (2026)
- Record low
- 39°4° (1959)
- Heating degree days
- 13
- Cooling degree days
- 244
Rapid City in August
Highs average 85°30° and lows 56°13°, with 1.6 in40 mm of precipitation in a typical August.
- Record high
- 107°42° (2007)
- Record low
- 37°3° (2020)
- Heating degree days
- 25
- Cooling degree days
- 205
Rapid City in September
Highs average 76°24° and lows 46°8°, with 1.2 in31 mm of precipitation and 0.1 in0.3 cm of snow in a typical September.
- Record high
- 104°40° (1960)
- Record low
- 18°−8° (1942)
- Heating degree days
- 175
- Cooling degree days
- 62
Rapid City in OctoberThis month
Highs average 60°16° and lows 34°1°, with 1.4 in36 mm of precipitation and 3 in8 cm of snow in a typical October.
- Record high
- 96°36° (2011)
- Record low
- −7°−22° (2020)
- Heating degree days
- 560
- Cooling degree days
- 3
Rapid City in November
Highs average 47°8° and lows 22°−6°, with 0.47 in12 mm of precipitation and 6 in14 cm of snow in a typical November.
- Record high
- 83°28° (1999)
- Record low
- −19°−28° (1959)
- Heating degree days
- 912
- Cooling degree days
- 0
Rapid City in December
Highs average 37°3° and lows 14°−10°, with 0.35 in8.9 mm of precipitation and 7 in17 cm of snow in a typical December.
- Record high
- 75°24° (1965)
- Record low
- −30°−34° (1990)
- Heating degree days
- 1223
- Cooling degree days
- 0