S
M
T
W
T
F
S
26
67°
43°
27
69°
47°
28
71°
48°
29
72°
48°
30
74°
49°
1
75°
49°
2
75°
50°
3
72°
49°
4
73°
50°
5
75°
48°
6
71°
47°
7
74°
49°
8
70°
48°
9
69°
49°
10
69°
48°
11
70°
48°
12
71°
49°
13
70°
46°
14
71°
46°
15
73°
50°
16
71°
51°
17
70°
50°
18
71°
51°
19
72°
50°
20
73°
50°
21
78°
52°
22
79°
53°
23
80°
54°
24
80°
55°
25
81°
55°
26
82°
54°
27
81°
55°
28
81°
55°
29
80°
54°
30
78°
51°
31
75°
49°
1
73°
49°
2
75°
50°
3
74°
51°
4
76°
54°
5
80°
53°
6
82°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Napa
Napa's May 2026 forecast shows daily high temperatures ranging from 67° to 82°, with overnight lows between 43° and 55°. The average high for May is 74° with an average low of 50°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how May weather will actually feel in Napa. See also: June | July | August.
