Keystone weather live forecast

Today's maximum temperature in Keystone is expected to be 59°F. Select a day from the live weather forecast for Keystone, South Dakota, USA for more weather parameters.

Thursday
7th May
59

39

3

4
Friday
8th May
66

45

7

6
Saturday
9th May
59

45

2

3
Sunday
10th May
64

43

8

6
Monday
11th May
79

48

10

7

5-day weather forecast updated at 04:03 on Thursday 7th May 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 7th May 2026

Expect mostly cloudy with light rain in Keystone, South Dakota with a maximum temperature of 59°F, maximum UV of 4 (Moderate) and 3 hours of bright sunshine. There are 2-5 mm of rainfall expected with 74% chance of some rain and a light breeze of 6 mph from the west.

59
°F maximum temperature
39
°F minimum temperature
mostly cloudy with light rain
3
hours of sunshine
4
UV index (Moderate)
74
% chance of some rain
<5
mm of rainfall expected
59
°F wind chill
6
mph wind from W

Keystone weather for Friday 8th May 2026

Expect sunshine and showers in Keystone, South Dakota with a maximum temperature of 66°F, maximum UV of 6 (High) and 7 hours of bright sunshine. There are 0-2 mm of rainfall expected with 8% chance of some rain and a gentle breeze of 9 mph from the north-west.

66
°F maximum temperature
45
°F minimum temperature
sunshine and showers
7
hours of sunshine
6
UV index (High)
8
% chance of some rain
<2
mm of rainfall expected
66
°F wind chill
9
mph wind from NW

Keystone weather for Saturday 9th May 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 59°F, maximum UV of 3 (Moderate) and 2 hours of bright sunshine. There are 5-10 mm of rainfall expected with 88% chance of some rain and a light breeze of 7 mph from the north.

59
°F maximum temperature
45
°F minimum temperature
isolated thunderstorms
2
hours of sunshine
3
UV index (Moderate)
88
% chance of some rain
<10
mm of rainfall expected
59
°F wind chill
7
mph wind from N

Keystone weather for Sunday 10th May 2026

Expect broken clouds in Keystone, South Dakota with a maximum temperature of 64°F, maximum UV of 6 (High) and 8 hours of bright sunshine. There are 0 mm of rainfall expected and little or no wind of 4 mph from the east.

64
°F maximum temperature
43
°F minimum temperature
broken clouds
8
hours of sunshine
6
UV index (High)
0
mm of rainfall expected
0
no heat & humidity
4
mph wind from E

Keystone weather for Monday 11th May 2026

Expect broken clouds in Keystone, South Dakota with a maximum temperature of 79°F, maximum UV of 7 (High) and 10 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 7 mph from the north-west.