Keystone weather live forecast

Today's maximum temperature in Keystone is expected to be 22°C. Select a day from the live weather forecast for Keystone, South Dakota, USA for more weather parameters.

Thursday
23rd Jul
22

18

3

7
Friday
24th Jul
33

17

11

10
Saturday
25th Jul
37

23

10

9
Sunday
26th Jul
37

26

11

9
Monday
27th Jul
34

24

14

9

5-day weather forecast updated at 04:03 on Thursday 23rd 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 Thursday 23rd July 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 22°C, maximum UV of 7 (High) and 3 hours of bright sunshine. There are 5-10 mm of rainfall expected with 85% chance of some rain and little or no wind of 6 kph from the south-west.

22
°C maximum temperature
18
°C minimum temperature
isolated thunderstorms
3
hours of sunshine
7
UV index (High)
85
% chance of some rain
<10
mm of rainfall expected
0
no heat & humidity
6
kph wind from SW

Keystone weather for Friday 24th July 2026

Expect scattered clouds in Keystone, South Dakota with a maximum temperature of 33°C, moderate levels of heat & humidity, maximum UV of 10 (Very High) and 11 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 8 kph from the west.

33
°C maximum temperature
17
°C minimum temperature
scattered clouds
11
hours of sunshine
10
UV index (Very High)
0
mm of rainfall expected
M
moderate heat & humidity
8
kph wind from W

Keystone weather for Saturday 25th July 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 10 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 13 kph from the south-west.

37
°C maximum temperature
23
°C minimum temperature
scattered clouds
10
hours of sunshine
9
UV index (Very High)
0
mm of rainfall expected
H
high heat & humidity
13
kph wind from SW

Keystone weather for Sunday 26th July 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 11 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 12 kph from the west.

37
°C maximum temperature
26
°C minimum temperature
scattered clouds
11
hours of sunshine
9
UV index (Very High)
0
mm of rainfall expected
H
high heat & humidity
12
kph wind from W

Keystone weather for Monday 27th July 2026

Expect scattered clouds in Keystone, South Dakota with a maximum temperature of 34°C, high levels of heat & humidity, maximum UV of 9 (Very High) and 14 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 8 kph from the west.