Keystone weather live forecast

Today's maximum temperature in Keystone is expected to be 28°C. Select a day from the live weather forecast for Keystone, South Dakota, USA for more weather parameters.

Friday
31st Jul
28

16

13

8
Saturday
1st Aug
33

18

12

9
Sunday
2nd Aug
37

23

12

9
Monday
3rd Aug
28

17

9

9
Tuesday
4th Aug
22

13

6

7

5-day weather forecast updated at 04:03 on Friday 31st July 2026 GMT

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The 5-day weather forecast for South Dakota (Keystone) is provided by the Swiss meteorological agency, meteoblue. Find out more about our data sources.

Keystone weather forecast by day

Below are the detailed weather forecasts for Keystone for the next 5 days.

Keystone weather for Friday 31st July 2026

Expect scattered clouds in Keystone, South Dakota with a maximum temperature of 28°C, low levels of heat & humidity, maximum UV of 8 (Very High) and 13 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 10 kph from the north-west.

28
°C maximum temperature
16
°C minimum temperature
scattered clouds
13
hours of sunshine
8
UV index (Very High)
0
mm of rainfall expected
L
low heat & humidity
10
kph wind from NW

Keystone weather for Saturday 1st August 2026

Expect clear skies in Keystone, South Dakota with a maximum temperature of 33°C, moderate levels of heat & humidity, maximum UV of 9 (Very High) and 12 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 13 kph from the south.

33
°C maximum temperature
18
°C minimum temperature
clear skies
12
hours of sunshine
9
UV index (Very High)
0
mm of rainfall expected
M
moderate heat & humidity
13
kph wind from S

Keystone weather for Sunday 2nd August 2026

Expect scattered clouds in Keystone, South Dakota with a maximum temperature of 37°C, high levels of heat & humidity, maximum UV of 9 (Very High) and 12 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 16 kph from the south-west.

37
°C maximum temperature
23
°C minimum temperature
scattered clouds
12
hours of sunshine
9
UV index (Very High)
0
mm of rainfall expected
H
high heat & humidity
16
kph wind from SW

Keystone weather for Monday 3rd August 2026

Expect broken clouds in Keystone, South Dakota with a maximum temperature of 28°C, low levels of heat & humidity, maximum UV of 9 (Very High) and 9 hours of bright sunshine. There are 0 mm of rainfall expected and a moderate breeze of 21 kph from the north.

28
°C maximum temperature
17
°C minimum temperature
broken clouds
9
hours of sunshine
9
UV index (Very High)
0
mm of rainfall expected
L
low heat & humidity
21
kph wind from N

Keystone weather for Tuesday 4th August 2026

Expect broken clouds in Keystone, South Dakota with a maximum temperature of 22°C, maximum UV of 7 (High) and 6 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 16 kph from the north.