Keystone town, South Dakota

Official LSAD Designation: Keystone town • Census GEOID: 4633820 • Pennington County

Climate Normals & Weather Observations

30-year climate normals (1991–2020) and weather observations for Keystone town.

Reference Weather Station: MT RUSHMORE NMEM, SD US (ID: USC00395870) • Located 2.0 miles from community center • Elevation: 1,618.8 m

Month	Average High (°F)	Average Low (°F)	Mean Temp (°F)	Precipitation (in)
January	36.8°	18.8°	27.8°	0.48"
February	36.3°	18.4°	27.3°	0.76"
March	44.2°	25.4°	34.8°	1.35"
April	50.2°	31.8°	41.0°	2.62"
May	59.6°	41.5°	50.6°	4.80"
June	71.1°	51.9°	61.5°	3.58"
July	78.7°	59.1°	68.9°	3.59"
August	77.5°	58.0°	67.8°	2.29"
September	69.1°	49.6°	59.4°	1.76"
October	55.0°	36.8°	45.9°	1.80"
November	44.4°	27.0°	35.7°	0.59"
December	36.6°	19.8°	28.2°	0.50"

2010–2025, completed calendar years only.

NOAA station MT RUSHMORE NMEM, SD US (ID: USC00395870) • 2.0 miles from community center .

This is the same reference station used for monthly normals.

Show annual mean of daily highs and lows

Annual mean Annual mean of daily highs Annual mean of daily lows

Annual temperature data table (°F)

Annual station temperatures, 2010–2025. Unavailable means no reported value.
Year	Annual mean (°F)	Annual mean of daily highs (°F)	Annual mean of daily lows (°F)
2010	46.0	55.2	36.9
2011	45.1	54.1	36.1
2012	49.2	59.2	39.2
2013	Unavailable	Unavailable	35.7
2014	44.3	53.5	35.2
2015	47.6	56.7	38.6
2016	48.6	57.6	39.6
2017	46.9	56.2	37.5
2018	Unavailable	Unavailable	Unavailable
2019	42.7	51.6	33.8
2020	Unavailable	Unavailable	Unavailable
2021	47.0	56.7	37.4
2022	45.5	55.9	35.2
2023	45.7	54.7	36.6
2024	48.0	57.5	38.5
2025	46.6	56.0	37.2

Source: NOAA NCEI 1991–2020 U.S. Climate Normals, National Weather Service.