Keystone weather live forecast

Today's maximum temperature in Keystone is expected to be 30°C. Select a day from the live weather forecast for Keystone, South Dakota, USA for more weather parameters.

Tuesday
11th Aug
30

17

9

7
Wednesday
12th Aug
26

16

6

4
Thursday
13th Aug
19

15

3

6
Friday
14th Aug
22

15

4

8
Saturday
15th Aug
22

15

4

7

5-day weather forecast updated at 04:03 on Tuesday 11th 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 11th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 30°C, moderate levels of heat & humidity, maximum UV of 7 (High) and 9 hours of bright sunshine. There are 2-5 mm of rainfall expected with 43% chance of some rain and a light breeze of 10 kph from the south-east.

30
°C maximum temperature
17
°C minimum temperature
isolated thunderstorms
9
hours of sunshine
7
UV index (High)
43
% chance of some rain
<5
mm of rainfall expected
M
moderate heat & humidity
10
kph wind from SE

Keystone weather for Wednesday 12th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 26°C, maximum UV of 4 (Moderate) and 6 hours of bright sunshine. There are 5-10 mm of rainfall expected with 67% chance of some rain and a light breeze of 9 kph from the east.

26
°C maximum temperature
16
°C minimum temperature
isolated thunderstorms
6
hours of sunshine
4
UV index (Moderate)
67
% chance of some rain
<10
mm of rainfall expected
26
°C wind chill
9
kph wind from E

Keystone weather for Thursday 13th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 19°C, maximum UV of 6 (High) and 3 hours of bright sunshine. There are 10-20 mm of rainfall expected with 74% chance of some rain and a light breeze of 11 kph from the south-east.

19
°C maximum temperature
15
°C minimum temperature
isolated thunderstorms
3
hours of sunshine
6
UV index (High)
74
% chance of some rain
<20
mm of rainfall expected
0
no heat & humidity
11
kph wind from SE

Keystone weather for Friday 14th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 22°C, maximum UV of 8 (Very High) and 4 hours of bright sunshine. There are 5-10 mm of rainfall expected with 70% chance of some rain and a light breeze of 9 kph from the south.

22
°C maximum temperature
15
°C minimum temperature
isolated thunderstorms
4
hours of sunshine
8
UV index (Very High)
70
% chance of some rain
<10
mm of rainfall expected
0
no heat & humidity
9
kph wind from S

Keystone weather for Saturday 15th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 22°C, maximum UV of 7 (High) and 4 hours of bright sunshine. There are 5-10 mm of rainfall expected with 70% chance of some rain and a light breeze of 7 kph from the east.