S
M
T
W
T
F
S
26
92°
77°
27
92°
77°
28
96°
80°
29
96°
76°
30
94°
78°
1
86°
67°
2
77°
62°
3
86°
62°
4
85°
66°
5
94°
77°
6
101°
81°
7
84°
73°
8
90°
72°
9
93°
71°
10
95°
75°
11
90°
70°
12
92°
70°
13
93°
70°
14
95°
68°
15
93°
72°
16
94°
76°
17
93°
81°
18
97°
79°
19
96°
81°
20
93°
70°
21
87°
71°
22
95°
75°
23
87°
73°
24
95°
78°
25
95°
75°
26
92°
73°
27
83°
69°
28
94°
73°
29
95°
75°
30
98°
76°
31
97°
77°
1
92°
77°
2
94°
78°
3
90°
75°
4
90°
77°
5
90°
78°
6
93°
77°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in McAllen
McAllen's May 2026 forecast shows daily high temperatures ranging from 90° to 98°, with overnight lows between 75° and 78°. The average high for May is 93° with an average low of 77°. 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 McAllen. See also: June | July | August.
