Lewistown weather by month

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

Temperature
Rainfall
Sunshine & daylight
UV levels & humidity

Temperature in Lewistown (°C)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	-1	2	5	12	17	22	27	27	20	15	6	0
Min temperature (night-time)	-13	-10	-7	-2	3	7	10	10	5	0	-7	-12
Heat & Humidity	0	0	0	0	0	0	L	L	0	0	0	0

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

Sunshine & Daylight in Lewistown

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Daily hours of sunshine	4	6	8	9	10	11	12	11	9	7	4	4
Daily hours of daylight	9	10	12	14	15	16	15	14	13	11	9	9
UV Index (Maximum)	1	2	3	5	7	8	8	7	5	3	1	1

Rainfall in Lewistown

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Number of days with some rain	8	7	8	9	11	10	7	7	7	5	6	7
Average monthly rainfall (mm)	21	16	23	31	82	78	43	45	37	26	18	19

More about Lewistown

Lewistown by month

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

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The climate guide for Montana (Lewistown) 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 Lewistown?

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

Lewistown weather in January

Expect daytime maximum temperatures of -1°C in Lewistown, Montana in January based on long-term weather averages. There are 4 hours of sunshine per day on average, which might fall as snow.

-1
-1°C max day temperature
4
4 hours of sunshine per day
8
8 days with some rainfall
-13
-13°C min night temperature
9
9 hours of daylight per day
0
No heat & humidity
21
21 mm of monthly rainfall
1
1 (Low) UV index

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Lewistown weather in February

Expect daytime maximum temperatures of 2°C in Lewistown, Montana in February based on long-term weather averages. There are 6 hours of sunshine per day on average, which might fall as snow.

2
2°C max day temperature
6
6 hours of sunshine per day
7
7 days with some rainfall
-10
-10°C min night temperature
10
10 hours of daylight per day
0
No heat & humidity
16
16 mm of monthly rainfall
2
2 (Low) UV index

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Lewistown weather in March

Expect daytime maximum temperatures of 5°C in Lewistown, Montana in March based on long-term weather averages. There are 8 hours of sunshine per day on average, which might fall as snow.

5
5°C max day temperature
8
8 hours of sunshine per day
8
8 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
3
3 (Moderate) UV index

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Lewistown weather in April

Expect daytime maximum temperatures of 12°C in Lewistown, Montana in April based on long-term weather averages. There are 9 hours of sunshine per day on average.

12
12°C max day temperature
9
9 hours of sunshine per day
9
9 days with some rainfall
-2
-2°C min night temperature
14
14 hours of daylight per day
0
No heat & humidity
31
31 mm of monthly rainfall
5
5 (Moderate) UV index

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Lewistown weather in May

Expect daytime maximum temperatures of 17°C in Lewistown, Montana in May based on long-term weather averages. There are 10 hours of sunshine per day on average with 11 days with some rainfall and typically 82 mm of rainfall in the month.

17
17°C max day temperature
10
10 hours of sunshine per day
11
11 days with some rainfall
3
3°C min night temperature
15
15 hours of daylight per day
0
No heat & humidity
82
82 mm of monthly rainfall
7
7 (High) UV index

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Lewistown weather in June

Expect daytime maximum temperatures of 22°C in Lewistown, Montana in June based on long-term weather averages. There are 11 hours of sunshine per day on average with 10 days with some rainfall and typically 78 mm of rainfall in the month.

22
22°C max day temperature
11
11 hours of sunshine per day
10
10 days with some rainfall
7
7°C min night temperature
16
16 hours of daylight per day
0
No heat & humidity
78
78 mm of monthly rainfall
8
8 (Very High) UV index

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Lewistown weather in July

Expect daytime maximum temperatures of 27°C in Lewistown, Montana in July based on long-term weather averages. There are 12 hours of sunshine per day on average with typically 43 mm of rainfall in the month.

27
27°C max day temperature
12
12 hours of sunshine per day
7
7 days with some rainfall
10
10°C min night temperature
15
15 hours of daylight per day
L
Low heat & humidity
43
43 mm of monthly rainfall
8
8 (Very High) UV index

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Lewistown weather in August

Expect daytime maximum temperatures of 27°C in Lewistown, Montana in August based on long-term weather averages. There are 11 hours of sunshine per day on average with typically 45 mm of rainfall in the month.

27
27°C max day temperature
11
11 hours of sunshine per day
7
7 days with some rainfall
10
10°C min night temperature
14
14 hours of daylight per day
L
Low heat & humidity
45
45 mm of monthly rainfall
7
7 (High) UV index

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Lewistown weather in September

Expect daytime maximum temperatures of 20°C in Lewistown, Montana in September based on long-term weather averages. There are 9 hours of sunshine per day on average.

20
20°C max day temperature
9
9 hours of sunshine per day
7
7 days with some rainfall
5
5°C min night temperature
13
13 hours of daylight per day
0
No heat & humidity
37
37 mm of monthly rainfall
5
5 (Moderate) UV index

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Lewistown weather in October

Expect daytime maximum temperatures of 15°C in Lewistown, Montana in October based on long-term weather averages. There are 7 hours of sunshine per day on average.

15
15°C max day temperature
7
7 hours of sunshine per day
5
5 days with some rainfall
0
0°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
26
26 mm of monthly rainfall
3
3 (Moderate) UV index

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Lewistown weather in November

Expect daytime maximum temperatures of 6°C in Lewistown, Montana in November based on long-term weather averages. There are 4 hours of sunshine per day on average, which might fall as snow.

6
6°C max day temperature
4
4 hours of sunshine per day
6
6 days with some rainfall
-7
-7°C min night temperature
9
9 hours of daylight per day
0
No heat & humidity
18
18 mm of monthly rainfall
1
1 (Low) UV index

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Lewistown weather in December

Expect daytime maximum temperatures of 0°C in Lewistown, Montana in December based on long-term weather averages. There are 4 hours of sunshine per day on average, which might fall as snow.

0
0°C max day temperature
4
4 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
19
19 mm of monthly rainfall
1
1 (Low) UV index

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