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.

Sunday
23rd Aug
30

18

7

7
Monday
24th Aug
30

18

8

6
Tuesday
25th Aug
26

16

8

7
Wednesday
26th Aug
26

14

8

7
Thursday
27th Aug
27

15

9

7

5-day weather forecast updated at 04:03 on Sunday 23rd 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 Sunday 23rd 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 7 hours of bright sunshine. There are 2-5 mm of rainfall expected with 60% chance of some rain and a light breeze of 8 kph from the south.

30
°C maximum temperature
18
°C minimum temperature
isolated thunderstorms
7
hours of sunshine
7
UV index (High)
60
% chance of some rain
<5
mm of rainfall expected
M
moderate heat & humidity
8
kph wind from S

Keystone weather for Monday 24th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 30°C, moderate levels of heat & humidity, maximum UV of 6 (High) and 8 hours of bright sunshine. There are 2-5 mm of rainfall expected with 44% chance of some rain and a light breeze of 8 kph from the west.

30
°C maximum temperature
18
°C minimum temperature
isolated thunderstorms
8
hours of sunshine
6
UV index (High)
44
% chance of some rain
<5
mm of rainfall expected
M
moderate heat & humidity
8
kph wind from W

Keystone weather for Tuesday 25th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 26°C, maximum UV of 7 (High) and 8 hours of bright sunshine. There are 2-5 mm of rainfall expected with 66% chance of some rain and little or no wind of 6 kph from the north-west.

26
°C maximum temperature
16
°C minimum temperature
isolated thunderstorms
8
hours of sunshine
7
UV index (High)
66
% chance of some rain
<5
mm of rainfall expected
26
°C wind chill
6
kph wind from NW

Keystone weather for Wednesday 26th August 2026

Expect scattered clouds in Keystone, South Dakota with a maximum temperature of 26°C, maximum UV of 7 (High) and 8 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 8 kph from the east.

26
°C maximum temperature
14
°C minimum temperature
scattered clouds
8
hours of sunshine
7
UV index (High)
0
mm of rainfall expected
26
°C wind chill
8
kph wind from E

Keystone weather for Thursday 27th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 27°C, low levels of heat & humidity, maximum UV of 7 (High) and 9 hours of bright sunshine. There are 2-5 mm of rainfall expected with 46% chance of some rain and a light breeze of 10 kph from the south-east.