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 (°F)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	55	61	63	68	73	79	82	82	81	75	63	55
Min temperature (night-time)	37	41	41	43	46	52	54	54	52	48	43	37
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 (inches)	6.2	4.5	3.8	1.9	0.6	0.2	0.0	0.1	0.4	1.6	3.9	5.0

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 55°F 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 6.2 inches of rainfall in the month.

55
55°F max day temperature
6
6 hours of sunshine per day
10
10 days with some rainfall
37
37°F min night temperature
10
10 hours of daylight per day
0
No heat & humidity
6.2
6.2 inches of monthly rainfall
2
2 (Low) UV index

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Napa weather in February

Expect daytime maximum temperatures of 61°F in Napa, California in February based on long-term weather averages. There are 7 hours of sunshine per day on average with typically 4.5 inches of rainfall in the month.

61
61°F max day temperature
7
7 hours of sunshine per day
9
9 days with some rainfall
41
41°F min night temperature
11
11 hours of daylight per day
0
No heat & humidity
4.5
4.5 inches of monthly rainfall
3
3 (Moderate) UV index

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Napa weather in March

Expect daytime maximum temperatures of 63°F 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 3.8 inches of rainfall in the month.

63
63°F max day temperature
9
9 hours of sunshine per day
10
10 days with some rainfall
41
41°F min night temperature
12
12 hours of daylight per day
0
No heat & humidity
3.8
3.8 inches of monthly rainfall
5
5 (Moderate) UV index

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Napa weather in April

Expect daytime maximum temperatures of 68°F in Napa, California in April based on long-term weather averages. There are 11 hours of sunshine per day on average with typically 1.9 inches of rainfall in the month.

68
68°F max day temperature
11
11 hours of sunshine per day
6
6 days with some rainfall
43
43°F min night temperature
13
13 hours of daylight per day
0
No heat & humidity
1.9
1.9 inches of monthly rainfall
7
7 (High) UV index

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Napa weather in May

Expect daytime maximum temperatures of 73°F in Napa, California in May based on long-term weather averages. There are 11 hours of sunshine per day on average.

73
73°F max day temperature
11
11 hours of sunshine per day
3
3 days with some rainfall
46
46°F min night temperature
14
14 hours of daylight per day
0
No heat & humidity
0.6
0.6 inches of monthly rainfall
8
8 (Very High) UV index

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Napa weather in June

Expect daytime maximum temperatures of 79°F in Napa, California in June based on long-term weather averages. There are 12 hours of sunshine per day on average.

79
79°F max day temperature
12
12 hours of sunshine per day
1
1 day with some rainfall
52
52°F min night temperature
15
15 hours of daylight per day
L
Low heat & humidity
0.2
0.2 inches of monthly rainfall
9
9 (Very High) UV index

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Napa weather in July

Expect daytime maximum temperatures of 82°F in Napa, California in July based on long-term weather averages. There are 12 hours of sunshine per day on average.

82
82°F max day temperature
12
12 hours of sunshine per day
1
1 day with some rainfall
54
54°F min night temperature
15
15 hours of daylight per day
M
Moderate heat & humidity
0.0
0.0 inches of monthly rainfall
9
9 (Very High) UV index

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Napa weather in August

Expect daytime maximum temperatures of 82°F in Napa, California in August based on long-term weather averages. There are 11 hours of sunshine per day on average.

82
82°F max day temperature
11
11 hours of sunshine per day
1
1 day with some rainfall
54
54°F min night temperature
14
14 hours of daylight per day
M
Moderate heat & humidity
0.1
0.1 inches of monthly rainfall
9
9 (Very High) UV index

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Napa weather in September

Expect daytime maximum temperatures of 81°F in Napa, California in September based on long-term weather averages. There are 10 hours of sunshine per day on average.

81
81°F max day temperature
10
10 hours of sunshine per day
2
2 days with some rainfall
52
52°F min night temperature
12
12 hours of daylight per day
M
Moderate heat & humidity
0.4
0.4 inches of monthly rainfall
7
7 (High) UV index

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Napa weather in October

Expect daytime maximum temperatures of 75°F in Napa, California in October based on long-term weather averages. There are 8 hours of sunshine per day on average with typically 1.6 inches of rainfall in the month.

75
75°F max day temperature
8
8 hours of sunshine per day
4
4 days with some rainfall
48
48°F min night temperature
11
11 hours of daylight per day
0
No heat & humidity
1.6
1.6 inches of monthly rainfall
5
5 (Moderate) UV index

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Napa weather in November

Expect daytime maximum temperatures of 63°F in Napa, California in November based on long-term weather averages. There are 6 hours of sunshine per day on average with typically 3.9 inches of rainfall in the month.

63
63°F max day temperature
6
6 hours of sunshine per day
9
9 days with some rainfall
43
43°F min night temperature
10
10 hours of daylight per day
0
No heat & humidity
3.9
3.9 inches of monthly rainfall
3
3 (Moderate) UV index

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Napa weather in December

Expect daytime maximum temperatures of 55°F 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 5.0 inches of rainfall in the month.