Keystone weather live forecast

Today's maximum temperature in Keystone is expected to be 25°C. Select a day from the live weather forecast for Keystone, South Dakota, USA for more weather parameters.

Tuesday
25th Aug
25

16

7

7
Wednesday
26th Aug
25

14

8

7
Thursday
27th Aug
27

15

10

7
Friday
28th Aug
31

18

9

7
Saturday
29th Aug
30

19

7

6

5-day weather forecast updated at 04:03 on Tuesday 25th 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 25th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 25°C, maximum UV of 7 (High) and 7 hours of bright sunshine. There are 2-5 mm of rainfall expected with 52% chance of some rain and little or no wind of 6 kph from the north-west.

25
°C maximum temperature
16
°C minimum temperature
isolated thunderstorms
7
hours of sunshine
7
UV index (High)
52
% chance of some rain
<5
mm of rainfall expected
25
°C wind chill
6
kph wind from NW

Keystone weather for Wednesday 26th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 25°C, maximum UV of 7 (High) and 8 hours of bright sunshine. There are 0-2 mm of rainfall expected with 35% chance of some rain and a light breeze of 7 kph from the south-east.

25
°C maximum temperature
14
°C minimum temperature
isolated thunderstorms
8
hours of sunshine
7
UV index (High)
35
% chance of some rain
<2
mm of rainfall expected
25
°C wind chill
7
kph wind from SE

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 10 hours of bright sunshine. There are 0-2 mm of rainfall expected with 55% chance of some rain and a light breeze of 9 kph from the south-east.

27
°C maximum temperature
15
°C minimum temperature
isolated thunderstorms
10
hours of sunshine
7
UV index (High)
55
% chance of some rain
<2
mm of rainfall expected
L
low heat & humidity
9
kph wind from SE

Keystone weather for Friday 28th August 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 31°C, moderate levels of heat & humidity, maximum UV of 7 (High) and 9 hours of bright sunshine. There are 0-2 mm of rainfall expected with 55% chance of some rain and a light breeze of 7 kph from the south-west.

31
°C maximum temperature
18
°C minimum temperature
isolated thunderstorms
9
hours of sunshine
7
UV index (High)
55
% chance of some rain
<2
mm of rainfall expected
M
moderate heat & humidity
7
kph wind from SW

Keystone weather for Saturday 29th 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 7 hours of bright sunshine. There are 0-2 mm of rainfall expected with 27% chance of some rain and a light breeze of 12 kph from the west.