Keystone weather live forecast

Today's maximum temperature in Keystone is expected to be 19°C. Select a day from the live weather forecast for Keystone, South Dakota, USA for more weather parameters.

Thursday
13th Aug
19

14

2

5
Friday
14th Aug
25

15

4

6
Saturday
15th Aug
21

15

2

3
Sunday
16th Aug
22

14

5

3
Monday
17th Aug
26

14

9

6

5-day weather forecast updated at 04:03 on Thursday 13th 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 Thursday 13th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 19°C, maximum UV of 5 (Moderate) and 2 hours of bright sunshine. There are 5-10 mm of rainfall expected with 56% chance of some rain and a light breeze of 10 kph from the east.

19
°C maximum temperature
14
°C minimum temperature
isolated thunderstorms
2
hours of sunshine
5
UV index (Moderate)
56
% chance of some rain
<10
mm of rainfall expected
0
no heat & humidity
10
kph wind from E

Keystone weather for Friday 14th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 25°C, maximum UV of 6 (High) and 4 hours of bright sunshine. There are 2-5 mm of rainfall expected with 58% chance of some rain and a light breeze of 8 kph from the south.

25
°C maximum temperature
15
°C minimum temperature
isolated thunderstorms
4
hours of sunshine
6
UV index (High)
58
% chance of some rain
<5
mm of rainfall expected
25
°C wind chill
8
kph wind from S

Keystone weather for Saturday 15th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 21°C, maximum UV of 3 (Moderate) and 2 hours of bright sunshine. There are 5-10 mm of rainfall expected with 84% chance of some rain and a light breeze of 7 kph from the north-east.

21
°C maximum temperature
15
°C minimum temperature
isolated thunderstorms
2
hours of sunshine
3
UV index (Moderate)
84
% chance of some rain
<10
mm of rainfall expected
21
°C wind chill
7
kph wind from NE

Keystone weather for Sunday 16th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 22°C, maximum UV of 3 (Moderate) and 5 hours of bright sunshine. There are 2-5 mm of rainfall expected with 72% chance of some rain and a light breeze of 9 kph from the south.

22
°C maximum temperature
14
°C minimum temperature
isolated thunderstorms
5
hours of sunshine
3
UV index (Moderate)
72
% chance of some rain
<5
mm of rainfall expected
0
no heat & humidity
9
kph wind from S

Keystone weather for Monday 17th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 26°C, low levels of heat & humidity, maximum UV of 6 (High) and 9 hours of bright sunshine. There are 2-5 mm of rainfall expected with 49% chance of some rain and a light breeze of 7 kph from the west.