S
M
T
W
T
F
S
26
71°
50°
27
74°
49°
28
75°
51°
29
79°
52°
30
82°
55°
1
80°
53°
2
78°
53°
3
77°
50°
4
78°
52°
5
75°
47°
6
72°
48°
7
72°
48°
8
73°
49°
9
74°
48°
10
74°
48°
11
76°
49°
12
75°
49°
13
79°
52°
14
77°
50°
15
75°
48°
16
74°
50°
17
76°
49°
18
81°
53°
19
80°
52°
20
82°
54°
21
83°
55°
22
78°
53°
23
76°
51°
24
81°
53°
25
79°
52°
26
77°
51°
27
76°
51°
28
77°
52°
29
77°
53°
30
79°
56°
31
83°
56°
1
81°
58°
2
87°
58°
3
88°
57°
4
87°
56°
5
88°
57°
6
87°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Simi Valley
Simi Valley's May 2026 forecast shows daily high temperatures ranging from 71° to 88°, with overnight lows between 47° and 58°. The average high for May is 78° with an average low of 52°. 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 Simi Valley. See also: June | July | August.
