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Rapid City September Weather

Averages and records for weather in Rapid City, South Dakota in the month of September.
Typical Rapid City September Weather
1991–2020
Average daily high 76.6 °F
Average daily low 46.7 °F
Average monthly precipitation 1.2 inches
Average monthly snow 0.1 inches
Rapid City September Weather Records
1948–2022
Highest temperature 104 °F September 5, 2020
Lowest temperature 18 °F September 24, 1985
Highest daily low 73 °F September 3, 1960
Lowest daily high 34 °F September 28, 1985
Hottest average temperature 5.8 °F
above average
1952
Coldest average temperature -11.6 °F
below average
1965
Most daily precipitation 2.1 inches September 13, 1966
Most monthly precipitation 3.2 inches 2014
Most daily snow 2.0 inches September 13, 1970
Most monthly snow 2.0 inches 1970
Note: Daily averages are a moving average which includes 14 days before and after
Day Average (°F) Record (°F)
High Low High Low
September 1 82.9 52.5 101 40
September 2 82.7 52.2 104 38
September 3 82.5 51.9 100 36
September 4 82.0 51.5 104 34
September 5 81.5 51.1 104 37
September 6 81.0 50.7 104 37
September 7 80.4 50.2 99 32
September 8 79.8 49.7 103 30
September 9 79.3 49.3 102 24
September 10 78.8 48.8 100 27
September 11 78.3 48.4 94 29
September 12 78.0 47.9 97 28
September 13 77.5 47.5 93 29
September 14 77.0 47.1 100 24
September 15 76.7 46.7 103 32
September 16 76.4 46.4 95 30
September 17 75.9 46.0 101 26
September 18 75.3 45.6 97 24
September 19 74.6 45.0 93 22
September 20 73.8 44.5 93 29
September 21 73.2 44.1 92 23
September 22 72.7 43.6 95 19
September 23 72.3 43.2 97 24
September 24 71.8 42.9 94 18
September 25 71.2 42.5 93 24
September 26 70.7 42.0 95 22
September 27 70.3 41.6 94 26
September 28 69.8 41.2 94 25
September 29 69.3 40.7 90 21
September 30 68.7 40.3 93 25
Weather Station Details
Years Station Coordinates
1948–2022 Rapid City Regional Airport location