Lewiston weather by month

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

Temperature
Rainfall
Sunshine & UV index

Temperature in Lewiston (°C)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	3	7	11	16	21	26	31	31	25	17	8	4
Min temperature (night-time)	-3	-1	1	3	7	11	13	13	9	4	0	-3
Heat & Humidity	0	0	0	0	0	0	M	M	0	0	0	0

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

Sunshine & UV index in Lewiston

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

Rainfall in Lewiston

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Number of days with some rain	11	10	11	10	9	8	5	5	6	7	11	12
Average monthly rainfall (mm)	41	29	34	33	37	35	17	21	21	29	39	40

More about Lewiston

Lewiston by month

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

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The climate guide for Idaho (Lewiston) 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 Lewiston?

Lewiston has a cool semi arid climate with hot summers.

Lewiston weather in January

Expect daytime maximum temperatures of 3°C in Lewiston, Idaho in January based on long-term weather averages. There are 3 hours of sunshine per day on average with 11 days with some rainfall and typically 41 mm of rainfall in the month, which might fall as snow.

3
3°C max day temperature
3
3 hours of sunshine per day
11
11 days with some rainfall
-3
-3°C min night temperature
9
9 hours of daylight per day
0
No heat & humidity
41
41 mm of monthly rainfall
1
1 (Low) UV index

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Lewiston weather in February

Expect daytime maximum temperatures of 7°C in Lewiston, Idaho in February based on long-term weather averages. There are 4 hours of sunshine per day on average with 10 days with some rainfall.

7
7°C max day temperature
4
4 hours of sunshine per day
10
10 days with some rainfall
-1
-1°C min night temperature
10
10 hours of daylight per day
0
No heat & humidity
29
29 mm of monthly rainfall
2
2 (Low) UV index

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Lewiston weather in March

Expect daytime maximum temperatures of 11°C in Lewiston, Idaho in March based on long-term weather averages. There are 6 hours of sunshine per day on average with 11 days with some rainfall.

11
11°C max day temperature
6
6 hours of sunshine per day
11
11 days with some rainfall
1
1°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
34
34 mm of monthly rainfall
3
3 (Moderate) UV index

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Lewiston weather in April

Expect daytime maximum temperatures of 16°C in Lewiston, Idaho in April based on long-term weather averages. There are 8 hours of sunshine per day on average with 10 days with some rainfall.

16
16°C max day temperature
8
8 hours of sunshine per day
10
10 days with some rainfall
3
3°C min night temperature
14
14 hours of daylight per day
0
No heat & humidity
33
33 mm of monthly rainfall
5
5 (Moderate) UV index

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Lewiston weather in May

Expect daytime maximum temperatures of 21°C in Lewiston, Idaho in May based on long-term weather averages. There are 9 hours of sunshine per day on average.

21
21°C max day temperature
9
9 hours of sunshine per day
9
9 days with some rainfall
7
7°C min night temperature
15
15 hours of daylight per day
0
No heat & humidity
37
37 mm of monthly rainfall
7
7 (High) UV index

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Lewiston weather in June

Expect daytime maximum temperatures of 26°C in Lewiston, Idaho in June based on long-term weather averages. There are 10 hours of sunshine per day on average.

26
26°C max day temperature
10
10 hours of sunshine per day
8
8 days with some rainfall
11
11°C min night temperature
16
16 hours of daylight per day
0
No heat & humidity
35
35 mm of monthly rainfall
8
8 (Very High) UV index

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Lewiston weather in July

Expect daytime maximum temperatures of 31°C in Lewiston, Idaho in July based on long-term weather averages. There are 14 hours of sunshine per day on average.

31
31°C max day temperature
14
14 hours of sunshine per day
5
5 days with some rainfall
13
13°C min night temperature
15
15 hours of daylight per day
M
Moderate heat & humidity
17
17 mm of monthly rainfall
8
8 (Very High) UV index

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Lewiston weather in August

Expect daytime maximum temperatures of 31°C in Lewiston, Idaho in August based on long-term weather averages. There are 12 hours of sunshine per day on average.

31
31°C max day temperature
12
12 hours of sunshine per day
5
5 days with some rainfall
13
13°C min night temperature
14
14 hours of daylight per day
M
Moderate heat & humidity
21
21 mm of monthly rainfall
7
7 (High) UV index

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Lewiston weather in September

Expect daytime maximum temperatures of 25°C in Lewiston, Idaho in September based on long-term weather averages. There are 9 hours of sunshine per day on average.

25
25°C max day temperature
9
9 hours of sunshine per day
6
6 days with some rainfall
9
9°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
21
21 mm of monthly rainfall
5
5 (Moderate) UV index

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Lewiston weather in October

Expect daytime maximum temperatures of 17°C in Lewiston, Idaho in October based on long-term weather averages. There are 6 hours of sunshine per day on average.

17
17°C max day temperature
6
6 hours of sunshine per day
7
7 days with some rainfall
4
4°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
29
29 mm of monthly rainfall
3
3 (Moderate) UV index

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Lewiston weather in November

Expect daytime maximum temperatures of 8°C in Lewiston, Idaho in November based on long-term weather averages. There are 3 hours of sunshine per day on average with 11 days with some rainfall.

8
8°C max day temperature
3
3 hours of sunshine per day
11
11 days with some rainfall
0
0°C min night temperature
9
9 hours of daylight per day
0
No heat & humidity
39
39 mm of monthly rainfall
1
1 (Low) UV index

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Lewiston weather in December

Expect daytime maximum temperatures of 4°C in Lewiston, Idaho in December based on long-term weather averages. There are 2 hours of sunshine per day on average with 12 days with some rainfall and typically 40 mm of rainfall in the month, which might fall as snow.