Keystone weather live forecast

Today's maximum temperature in Keystone is expected to be 20°C. Select a day from the live weather forecast for Keystone, South Dakota, USA for more weather parameters.

Tuesday
4th Aug
20

10

5

6
Wednesday
5th Aug
25

12

7

6
Thursday
6th Aug
30

15

11

7
Friday
7th Aug
32

17

14

8
Saturday
8th Aug
35

21

11

7

5-day weather forecast updated at 04:03 on Tuesday 4th August 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 Tuesday 4th August 2026

Expect broken clouds in Keystone, South Dakota with a maximum temperature of 20°C, maximum UV of 6 (High) and 5 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 9 kph from the south-east.

20
°C maximum temperature
10
°C minimum temperature
broken clouds
5
hours of sunshine
6
UV index (High)
0
mm of rainfall expected
0
no heat & humidity
9
kph wind from SE

Keystone weather for Wednesday 5th August 2026

Expect broken clouds in Keystone, South Dakota with a maximum temperature of 25°C, maximum UV of 6 (High) and 7 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 8 kph from the south.

25
°C maximum temperature
12
°C minimum temperature
broken clouds
7
hours of sunshine
6
UV index (High)
0
mm of rainfall expected
25
°C wind chill
8
kph wind from S

Keystone weather for Thursday 6th August 2026

Expect scattered clouds in Keystone, South Dakota with a maximum temperature of 30°C, low levels of heat & humidity, maximum UV of 7 (High) and 11 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 8 kph from the west.

30
°C maximum temperature
15
°C minimum temperature
scattered clouds
11
hours of sunshine
7
UV index (High)
0
mm of rainfall expected
L
low heat & humidity
8
kph wind from W

Keystone weather for Friday 7th August 2026

Expect clear skies in Keystone, South Dakota with a maximum temperature of 32°C, moderate levels of heat & humidity, maximum UV of 8 (Very High) and 14 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 9 kph from the south-east.

32
°C maximum temperature
17
°C minimum temperature
clear skies
14
hours of sunshine
8
UV index (Very High)
0
mm of rainfall expected
M
moderate heat & humidity
9
kph wind from SE

Keystone weather for Saturday 8th August 2026

Expect scattered clouds in Keystone, South Dakota with a maximum temperature of 35°C, high levels of heat & humidity, maximum UV of 7 (High) and 11 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 12 kph from the north-east.