S
M
T
W
T
F
S
26
62°
49°
27
62°
51°
28
73°
46°
29
75°
51°
30
74°
52°
1
77°
54°
2
80°
55°
3
65°
55°
4
63°
52°
5
60°
50°
6
74°
49°
7
81°
55°
8
82°
56°
9
84°
59°
10
86°
58°
11
94°
61°
12
73°
58°
13
80°
55°
14
83°
57°
15
82°
59°
16
80°
58°
17
81°
56°
18
83°
58°
19
83°
57°
20
82°
60°
21
87°
60°
22
79°
57°
23
82°
58°
24
81°
59°
25
82°
56°
26
76°
52°
27
76°
53°
28
78°
52°
29
78°
53°
30
77°
52°
31
77°
53°
1
81°
58°
2
86°
60°
3
86°
60°
4
87°
61°
5
86°
60°
6
87°
61°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Fontana
Fontana's May 2026 forecast shows daily high temperatures ranging from 73° to 87°, with overnight lows between 52° and 61°. The average high for May is 81° with an average low of 57°. 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 Fontana. See also: June | July | August.
