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.

Saturday
15th Aug
20

15

4

5
Sunday
16th Aug
22

13

6

5
Monday
17th Aug
26

15

8

7
Tuesday
18th Aug
25

15

3

6
Wednesday
19th Aug
22

13

6

7

5-day weather forecast updated at 04:03 on Saturday 15th 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 Saturday 15th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 20°C, maximum UV of 5 (Moderate) and 4 hours of bright sunshine. There are 10-20 mm of rainfall expected with 97% chance of some rain and a light breeze of 7 kph from the north-west.

20
°C maximum temperature
15
°C minimum temperature
isolated thunderstorms
4
hours of sunshine
5
UV index (Moderate)
97
% chance of some rain
<20
mm of rainfall expected
0
no heat & humidity
7
kph wind from NW

Keystone weather for Sunday 16th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 22°C, maximum UV of 5 (Moderate) and 6 hours of bright sunshine. There are 5-10 mm of rainfall expected with 71% chance of some rain and a light breeze of 10 kph from the south.

22
°C maximum temperature
13
°C minimum temperature
isolated thunderstorms
6
hours of sunshine
5
UV index (Moderate)
71
% chance of some rain
<10
mm of rainfall expected
0
no heat & humidity
10
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 7 (High) and 8 hours of bright sunshine. There are 2-5 mm of rainfall expected with 71% chance of some rain and a light breeze of 7 kph from the west.

26
°C maximum temperature
15
°C minimum temperature
isolated thunderstorms
8
hours of sunshine
7
UV index (High)
71
% chance of some rain
<5
mm of rainfall expected
L
low heat & humidity
7
kph wind from W

Keystone weather for Tuesday 18th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 25°C, maximum UV of 6 (High) and 3 hours of bright sunshine. There are 2-5 mm of rainfall expected with 62% chance of some rain and little or no wind of 6 kph from the north.

25
°C maximum temperature
15
°C minimum temperature
isolated thunderstorms
3
hours of sunshine
6
UV index (High)
62
% chance of some rain
<5
mm of rainfall expected
25
°C wind chill
6
kph wind from N

Keystone weather for Wednesday 19th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 22°C, maximum UV of 7 (High) and 6 hours of bright sunshine. There are 2-5 mm of rainfall expected with 57% chance of some rain and a light breeze of 7 kph from the east.