S
M
T
W
T
F
S
26
79°
60°
27
83°
50°
28
85°
51°
29
87°
57°
30
89°
58°
1
88°
59°
2
92°
64°
3
96°
74°
4
80°
69°
5
77°
60°
6
82°
54°
7
93°
59°
8
99°
65°
9
104°
68°
10
105°
71°
11
109°
71°
12
104°
73°
13
100°
66°
14
99°
68°
15
98°
69°
16
100°
67°
17
96°
66°
18
98°
66°
19
100°
67°
20
102°
70°
21
103°
68°
22
98°
64°
23
97°
65°
24
99°
64°
25
101°
63°
26
96°
63°
27
94°
60°
28
94°
68°
29
95°
63°
30
97°
63°
31
94°
60°
1
95°
65°
2
99°
69°
3
103°
69°
4
105°
70°
5
106°
71°
6
107°
71°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Casa Grande
Casa Grande's May 2026 forecast shows daily high temperatures ranging from 94° to 107°, with overnight lows between 60° and 73°. The average high for May is 99° with an average low of 66°. 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 Casa Grande. See also: June | July | August.