May weather in Castlewood, SD
The average temperature in Castlewood in May is 55.5°F (43.6°F–67.3°F). Average precipitation: 3.18 inches.
May is a spring month in Castlewood, and is warmer than the annual average of 42.7°F. Daily temperatures swing about 23.7°F between overnight low and afternoon high. Daylight averages about 14h 38m. For travel, May is a comfortable month to visit.
Avg High
67.3°F
Avg Low
43.6°F
Precipitation
3.18 in
Daylight
14h 38m
May records in Castlewood
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| May 1 | 80.1°F (2018) | 24.1°F (2013) | 0.31 in (2024) |
| May 2 | 86.0°F (2021) | 25.0°F (2013) | 0.20 in (2024) |
| May 3 | 82.0°F (2015) | 18.0°F (2013) | 0.06 in (2024) |
| May 4 | 75.9°F (2012) | 19.9°F (2013) | 0.71 in (2024) |
| May 5 | 78.1°F (2018) | 25.0°F (2013) | 1.07 in (2012) |
| May 6 | 82.0°F (2016) | 28.0°F (2013) | 0.85 in (2012) |
| May 7 | 91.0°F (2016) | 28.0°F (2021) | 0.81 in (2024) |
| May 8 | 82.9°F (2017) | 28.0°F (2021) | 0.80 in (2022) |
| May 9 | 79.0°F (2017) | 28.9°F (2020) | 0.81 in (2019) |
| May 10 | 84.0°F (2025) | 27.0°F (2019) | 0.19 in (2016) |
| May 11 | 84.0°F (2025) | 27.0°F (2021) | 0.89 in (2016) |
| May 12 | 89.1°F (2025) | 21.9°F (2013) | 2.04 in (2022) |
| May 13 | 88.0°F (2025) | 28.9°F (2020) | 0.62 in (2014) |
| May 14 | 88.0°F (2013) | 28.0°F (2016) | 0.21 in (2021) |
| May 15 | 91.0°F (2013) | 28.0°F (2014) | 0.55 in (2025) |
| May 16 | 84.0°F (2012) | 23.0°F (2014) | 0.46 in (2025) |
| May 17 | 84.0°F (2018) | 33.1°F (2014) | 0.58 in (2015) |
| May 18 | 88.0°F (2012) | 32.0°F (2015) | 0.91 in (2017) |
| May 19 | 91.0°F (2012) | 33.1°F (2015) | 0.28 in (2013) |
| May 20 | 78.1°F (2012) | 30.0°F (2023) | 0.70 in (2025) |
| May 21 | 80.1°F (2014) | 35.1°F (2017) | 0.72 in (2017) |
| May 22 | 82.9°F (2016) | 32.0°F (2022) | 1.73 in (2024) |
| May 23 | 86.0°F (2012) | 34.0°F (2017) | 0.30 in (2016) |
| May 24 | 84.9°F (2018) | 37.9°F (2017) | 0.47 in (2020) |
| May 25 | 89.1°F (2018) | 39.9°F (2017) | 0.96 in (2015) |
| May 26 | 90.0°F (2018) | 39.0°F (2019) | 0.45 in (2016) |
| May 27 | 91.9°F (2018) | 41.0°F (2022) | 0.21 in (2013) |
| May 28 | 98.1°F (2018) | 39.0°F (2021) | 0.60 in (2021) |
| May 29 | 89.1°F (2018) | 37.9°F (2021) | 0.75 in (2016) |
| May 30 | 88.0°F (2014) | 37.0°F (2012) | 0.51 in (2013) |
| May 31 | 91.0°F (2014) | 37.0°F (2015) | 0.88 in (2022) |