Napa weather by month

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

Temperature
Rainfall
Sunshine & UV index

Temperature in Napa (°C)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	13	16	17	20	23	26	28	28	27	24	17	13
Min temperature (night-time)	3	5	5	6	8	11	12	12	11	9	6	3
Heat & Humidity	0	0	0	0	0	L	M	M	M	0	0	0

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

Sunshine & UV index in Napa

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

Rainfall in Napa

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Number of days with some rain	10	9	10	6	3	1	1	1	2	4	9	10
Average monthly rainfall (mm)	157	115	97	47	14	5	1	3	10	41	100	127

More about Napa

Napa by month

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

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The climate guide for California (Napa) 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 Napa?

Napa has a temperate climate with hot dry summers.

Napa weather in January

Expect daytime maximum temperatures of 13°C in Napa, California in January based on long-term weather averages. There are 6 hours of sunshine per day on average with 10 days with some rainfall and typically 157 mm of rainfall in the month.

13
13°C max day temperature
6
6 hours of sunshine per day
10
10 days with some rainfall
3
3°C min night temperature
10
10 hours of daylight per day
0
No heat & humidity
157
157 mm of monthly rainfall
2
2 (Low) UV index

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Napa weather in February

Expect daytime maximum temperatures of 16°C in Napa, California in February based on long-term weather averages. There are 7 hours of sunshine per day on average with typically 115 mm of rainfall in the month.

16
16°C max day temperature
7
7 hours of sunshine per day
9
9 days with some rainfall
5
5°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
115
115 mm of monthly rainfall
3
3 (Moderate) UV index

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Napa weather in March

Expect daytime maximum temperatures of 17°C in Napa, California in March based on long-term weather averages. There are 9 hours of sunshine per day on average with 10 days with some rainfall and typically 97 mm of rainfall in the month.

17
17°C max day temperature
9
9 hours of sunshine per day
10
10 days with some rainfall
5
5°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
97
97 mm of monthly rainfall
5
5 (Moderate) UV index

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Napa weather in April

Expect daytime maximum temperatures of 20°C in Napa, California in April based on long-term weather averages. There are 11 hours of sunshine per day on average with typically 47 mm of rainfall in the month.

20
20°C max day temperature
11
11 hours of sunshine per day
6
6 days with some rainfall
6
6°C min night temperature
13
13 hours of daylight per day
0
No heat & humidity
47
47 mm of monthly rainfall
7
7 (High) UV index

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Napa weather in May

Expect daytime maximum temperatures of 23°C in Napa, California in May based on long-term weather averages. There are 11 hours of sunshine per day on average.

23
23°C max day temperature
11
11 hours of sunshine per day
3
3 days with some rainfall
8
8°C min night temperature
14
14 hours of daylight per day
0
No heat & humidity
14
14 mm of monthly rainfall
8
8 (Very High) UV index

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Napa weather in June

Expect daytime maximum temperatures of 26°C in Napa, California in June based on long-term weather averages. There are 12 hours of sunshine per day on average.

26
26°C max day temperature
12
12 hours of sunshine per day
1
1 day with some rainfall
11
11°C min night temperature
15
15 hours of daylight per day
L
Low heat & humidity
5
5 mm of monthly rainfall
9
9 (Very High) UV index

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Napa weather in July

Expect daytime maximum temperatures of 28°C in Napa, California in July based on long-term weather averages. There are 12 hours of sunshine per day on average.

28
28°C max day temperature
12
12 hours of sunshine per day
1
1 day with some rainfall
12
12°C min night temperature
15
15 hours of daylight per day
M
Moderate heat & humidity
1
1 mm of monthly rainfall
9
9 (Very High) UV index

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Napa weather in August

Expect daytime maximum temperatures of 28°C in Napa, California in August based on long-term weather averages. There are 11 hours of sunshine per day on average.

28
28°C max day temperature
11
11 hours of sunshine per day
1
1 day with some rainfall
12
12°C min night temperature
14
14 hours of daylight per day
M
Moderate heat & humidity
3
3 mm of monthly rainfall
9
9 (Very High) UV index

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Napa weather in September

Expect daytime maximum temperatures of 27°C in Napa, California in September based on long-term weather averages. There are 10 hours of sunshine per day on average.

27
27°C max day temperature
10
10 hours of sunshine per day
2
2 days with some rainfall
11
11°C min night temperature
12
12 hours of daylight per day
M
Moderate heat & humidity
10
10 mm of monthly rainfall
7
7 (High) UV index

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Napa weather in October

Expect daytime maximum temperatures of 24°C in Napa, California in October based on long-term weather averages. There are 8 hours of sunshine per day on average with typically 41 mm of rainfall in the month.

24
24°C max day temperature
8
8 hours of sunshine per day
4
4 days with some rainfall
9
9°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
41
41 mm of monthly rainfall
5
5 (Moderate) UV index

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Napa weather in November

Expect daytime maximum temperatures of 17°C in Napa, California in November based on long-term weather averages. There are 6 hours of sunshine per day on average with typically 100 mm of rainfall in the month.

17
17°C max day temperature
6
6 hours of sunshine per day
9
9 days with some rainfall
6
6°C min night temperature
10
10 hours of daylight per day
0
No heat & humidity
100
100 mm of monthly rainfall
3
3 (Moderate) UV index

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Napa weather in December

Expect daytime maximum temperatures of 13°C in Napa, California in December based on long-term weather averages. There are 5 hours of sunshine per day on average with 10 days with some rainfall and typically 127 mm of rainfall in the month.