Keystone weather live forecast

Today's maximum temperature in Keystone is expected to be 36°C. Select a day from the live weather forecast for Keystone, South Dakota, USA for more weather parameters.

Friday
24th Jul
36

16

15

10
Saturday
25th Jul
37

25

8

9
Sunday
26th Jul
37

25

11

10
Monday
27th Jul
34

23

8

9
Tuesday
28th Jul
32

22

6

9

5-day weather forecast updated at 04:03 on Saturday 25th July 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 Friday 24th July 2026

Expect clear skies in Keystone, South Dakota with a maximum temperature of 36°C, high levels of heat & humidity, maximum UV of 10 (Very High) and 15 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 7 kph from the west.

36
°C maximum temperature
16
°C minimum temperature
clear skies
15
hours of sunshine
10
UV index (Very High)
0
mm of rainfall expected
H
high heat & humidity
7
kph wind from W

Keystone weather for Saturday 25th July 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 37°C, high levels of heat & humidity, maximum UV of 9 (Very High) and 8 hours of bright sunshine. There are 0-2 mm of rainfall expected with 35% chance of some rain and a gentle breeze of 13 kph from the south-west.

37
°C maximum temperature
25
°C minimum temperature
isolated thunderstorms
8
hours of sunshine
9
UV index (Very High)
35
% chance of some rain
<2
mm of rainfall expected
H
high heat & humidity
13
kph wind from SW

Keystone weather for Sunday 26th July 2026

Expect scattered clouds in Keystone, South Dakota with a maximum temperature of 37°C, high levels of heat & humidity, maximum UV of 10 (Very High) and 11 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 12 kph from the north.

37
°C maximum temperature
25
°C minimum temperature
scattered clouds
11
hours of sunshine
10
UV index (Very High)
0
mm of rainfall expected
H
high heat & humidity
12
kph wind from N

Keystone weather for Monday 27th July 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 34°C, high levels of heat & humidity, maximum UV of 9 (Very High) and 8 hours of bright sunshine. There are 2-5 mm of rainfall expected with 47% chance of some rain and a light breeze of 11 kph from the south-east.

34
°C maximum temperature
23
°C minimum temperature
isolated thunderstorms
8
hours of sunshine
9
UV index (Very High)
47
% chance of some rain
<5
mm of rainfall expected
H
high heat & humidity
11
kph wind from SE

Keystone weather for Tuesday 28th July 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 32°C, moderate levels of heat & humidity, maximum UV of 9 (Very High) and 6 hours of bright sunshine. There are 2-5 mm of rainfall expected with 32% chance of some rain and a light breeze of 10 kph from the east.