The temperatures in South Dakota in May are usually low and can range between 10°C and 20°C.
You can expect rain for roughly half of the month of May in South Dakota. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in South Dakota in May 2025.
If you’re planning to visit South Dakota in the near future, we highly recommend that you review the 14 day weather forecast for South Dakota before you arrive.
Temperatures
20° / 10°
Rainy Days
9
Snowy Days
0
Dry Days
22
Rainfall
135
mm
Sun Hours
8.9
Hrs
