Keystone weather by month

Check out Keystone weather averages by month. Compare detailed monthly climate statistics including temperature, rainfall and sunshine figures.

Temperature
Rainfall
Sunshine & UV index

Temperature in Keystone (°C)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	1	3	7	14	19	25	29	28	23	16	7	2
Min temperature (night-time)	-12	-10	-7	-1	5	10	13	12	6	1	-6	-11
Heat & Humidity	0	0	0	0	0	0	M	L	0	0	0	0

Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme

Sunshine & UV index in Keystone

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Daily hours of sunshine	5	6	8	8	9	10	11	10	9	7	5	5
Daily hours of daylight	9	11	12	13	15	15	15	14	12	11	10	9
UV Index (Maximum)	1	2	4	6	7	9	9	8	6	3	2	1

Rainfall in Keystone

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Number of days with some rain	7	8	9	10	12	12	10	8	8	6	6	7
Average monthly rainfall (mm)	9	13	23	46	77	77	61	44	32	25	13	11

More about Keystone

Keystone by month

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

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The climate guide for South Dakota (Keystone) shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

What's the climate like in Keystone?

Keystone has a cold climate with warm summers and some rainfall in all months.

Keystone weather in January

Expect daytime maximum temperatures of 1°C in Keystone, South Dakota in January based on long-term weather averages. There are 5 hours of sunshine per day on average, which might fall as snow.

1
1°C max day temperature
5
5 hours of sunshine per day
7
7 days with some rainfall
-12
-12°C min night temperature
9
9 hours of daylight per day
0
No heat & humidity
9
9 mm of monthly rainfall
1
1 (Low) UV index

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Keystone weather in February

Expect daytime maximum temperatures of 3°C in Keystone, South Dakota in February based on long-term weather averages. There are 6 hours of sunshine per day on average, which might fall as snow.

3
3°C max day temperature
6
6 hours of sunshine per day
8
8 days with some rainfall
-10
-10°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
13
13 mm of monthly rainfall
2
2 (Low) UV index

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Keystone weather in March

Expect daytime maximum temperatures of 7°C in Keystone, South Dakota in March based on long-term weather averages. There are 8 hours of sunshine per day on average, which might fall as snow.

7
7°C max day temperature
8
8 hours of sunshine per day
9
9 days with some rainfall
-7
-7°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
23
23 mm of monthly rainfall
4
4 (Moderate) UV index

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Keystone weather in April

Expect daytime maximum temperatures of 14°C in Keystone, South Dakota in April based on long-term weather averages. There are 8 hours of sunshine per day on average with 10 days with some rainfall and typically 46 mm of rainfall in the month.

14
14°C max day temperature
8
8 hours of sunshine per day
10
10 days with some rainfall
-1
-1°C min night temperature
13
13 hours of daylight per day
0
No heat & humidity
46
46 mm of monthly rainfall
6
6 (High) UV index

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Keystone weather in May

Expect daytime maximum temperatures of 19°C in Keystone, South Dakota in May based on long-term weather averages. There are 9 hours of sunshine per day on average with 12 days with some rainfall and typically 77 mm of rainfall in the month.

19
19°C max day temperature
9
9 hours of sunshine per day
12
12 days with some rainfall
5
5°C min night temperature
15
15 hours of daylight per day
0
No heat & humidity
77
77 mm of monthly rainfall
7
7 (High) UV index

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Keystone weather in June

Expect daytime maximum temperatures of 25°C in Keystone, South Dakota in June based on long-term weather averages. There are 10 hours of sunshine per day on average with 12 days with some rainfall and typically 77 mm of rainfall in the month.

25
25°C max day temperature
10
10 hours of sunshine per day
12
12 days with some rainfall
10
10°C min night temperature
15
15 hours of daylight per day
0
No heat & humidity
77
77 mm of monthly rainfall
9
9 (Very High) UV index

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Keystone weather in July

Expect daytime maximum temperatures of 29°C in Keystone, South Dakota in July based on long-term weather averages. There are 11 hours of sunshine per day on average with 10 days with some rainfall and typically 61 mm of rainfall in the month.

29
29°C max day temperature
11
11 hours of sunshine per day
10
10 days with some rainfall
13
13°C min night temperature
15
15 hours of daylight per day
M
Moderate heat & humidity
61
61 mm of monthly rainfall
9
9 (Very High) UV index

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Keystone weather in August

Expect daytime maximum temperatures of 28°C in Keystone, South Dakota in August based on long-term weather averages. There are 10 hours of sunshine per day on average with typically 44 mm of rainfall in the month.

28
28°C max day temperature
10
10 hours of sunshine per day
8
8 days with some rainfall
12
12°C min night temperature
14
14 hours of daylight per day
L
Low heat & humidity
44
44 mm of monthly rainfall
8
8 (Very High) UV index

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Keystone weather in September

Expect daytime maximum temperatures of 23°C in Keystone, South Dakota in September based on long-term weather averages. There are 9 hours of sunshine per day on average.

23
23°C max day temperature
9
9 hours of sunshine per day
8
8 days with some rainfall
6
6°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
32
32 mm of monthly rainfall
6
6 (High) UV index

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Keystone weather in October

Expect daytime maximum temperatures of 16°C in Keystone, South Dakota in October based on long-term weather averages. There are 7 hours of sunshine per day on average.

16
16°C max day temperature
7
7 hours of sunshine per day
6
6 days with some rainfall
1
1°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
25
25 mm of monthly rainfall
3
3 (Moderate) UV index

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Keystone weather in November

Expect daytime maximum temperatures of 7°C in Keystone, South Dakota in November based on long-term weather averages. There are 5 hours of sunshine per day on average, which might fall as snow.

7
7°C max day temperature
5
5 hours of sunshine per day
6
6 days with some rainfall
-6
-6°C min night temperature
10
10 hours of daylight per day
0
No heat & humidity
13
13 mm of monthly rainfall
2
2 (Low) UV index

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Keystone weather in December

Expect daytime maximum temperatures of 2°C in Keystone, South Dakota in December based on long-term weather averages. There are 5 hours of sunshine per day on average, which might fall as snow.