S
M
T
W
T
F
S
26
59°
50°
27
64°
49°
28
71°
46°
29
75°
47°
30
74°
46°
1
75°
46°
2
59°
50°
3
65°
53°
4
62°
46°
5
63°
50°
6
72°
53°
7
72°
50°
8
71°
48°
9
75°
47°
10
72°
51°
11
79°
47°
12
79°
50°
13
69°
54°
14
78°
47°
15
77°
48°
16
76°
48°
17
74°
64°
18
81°
51°
19
77°
53°
20
71°
53°
21
80°
52°
22
73°
51°
23
72°
52°
24
70°
50°
25
74°
53°
26
76°
52°
27
75°
51°
28
76°
52°
29
75°
51°
30
70°
48°
31
74°
51°
1
78°
54°
2
78°
55°
3
77°
55°
4
80°
54°
5
79°
55°
6
78°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Mill Valley
Mill Valley's May 2026 forecast shows daily high temperatures ranging from 70° to 81°, with overnight lows between 48° and 64°. The average high for May is 76° with an average low of 53°. 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 Mill Valley. See also: June | July | August.
