Keystone weather live forecast

Today's maximum temperature in Keystone is expected to be 26°C. Select a day from the live weather forecast for Keystone, South Dakota, USA for more weather parameters.

Wednesday
16th Sep
26

12

7

6
Thursday
17th Sep
17

13

1

5
Friday
18th Sep
22

13

5

6
Saturday
19th Sep
19

12

1

2
Sunday
20th Sep
19

11

5

6

5-day weather forecast updated at 04:03 on Wednesday 16th September 2026 GMT

More about Keystone

Keystone by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for South Dakota

GO Airport Shuttle discount code: 5% off airport transfers

Discount Code

Save EXTRA 5% on airport transfers worldwide
Book private taxis & shuttle buses with discount code
Enter in coupon box on 'Reservations' page

Show discount code

******WEB

Redeem GO Airport Shuttle discount code >>

Expires at 23:59 on Thursday 31st Dec 2026

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 Wednesday 16th September 2026

Expect sunshine and showers in Keystone, South Dakota with a maximum temperature of 26°C, maximum UV of 6 (High) and 7 hours of bright sunshine. There are 0-2 mm of rainfall expected with 4% chance of some rain and a gentle breeze of 16 kph from the south.

26
°C maximum temperature
12
°C minimum temperature
sunshine and showers
7
hours of sunshine
6
UV index (High)
4
% chance of some rain
<2
mm of rainfall expected
26
°C wind chill
16
kph wind from S

Keystone weather for Thursday 17th September 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 17°C, maximum UV of 5 (Moderate) and 1 hour of bright sunshine. There are 10-20 mm of rainfall expected with 66% chance of some rain and a light breeze of 8 kph from the east.

17
°C maximum temperature
13
°C minimum temperature
isolated thunderstorms
1
hour of sunshine
5
UV index (Moderate)
66
% chance of some rain
<20
mm of rainfall expected
17
°C wind chill
8
kph wind from E

Keystone weather for Friday 18th September 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 22°C, maximum UV of 6 (High) and 5 hours of bright sunshine. There are 2-5 mm of rainfall expected with 45% chance of some rain and a light breeze of 9 kph from the east.

22
°C maximum temperature
13
°C minimum temperature
isolated thunderstorms
5
hours of sunshine
6
UV index (High)
45
% chance of some rain
<5
mm of rainfall expected
22
°C wind chill
9
kph wind from E

Keystone weather for Saturday 19th September 2026

Expect isolated thunderstorms in Keystone, South Dakota with a maximum temperature of 19°C, maximum UV of 2 (Low) and 1 hour of bright sunshine. There are 5-10 mm of rainfall expected with 73% chance of some rain and a light breeze of 8 kph from the south-east.

19
°C maximum temperature
12
°C minimum temperature
isolated thunderstorms
1
hour of sunshine
2
UV index (Low)
73
% chance of some rain
<10
mm of rainfall expected
0
no heat & humidity
8
kph wind from SE

Keystone weather for Sunday 20th September 2026

Expect broken clouds in Keystone, South Dakota with a maximum temperature of 19°C, maximum UV of 6 (High) and 5 hours of bright sunshine. There are 0 mm of rainfall expected and little or no wind of 6 kph from the north.