S
M
T
W
T
F
S
26
60°
44°
27
74°
44°
28
71°
54°
29
58°
45°
30
54°
39°
1
49°
37°
2
45°
32°
3
59°
32°
4
72°
46°
5
68°
50°
6
58°
41°
7
57°
38°
8
64°
41°
9
69°
50°
10
65°
46°
11
67°
36°
12
69°
40°
13
65°
45°
14
62°
42°
15
68°
37°
16
73°
59°
17
87°
62°
18
89°
66°
19
85°
62°
20
69°
45°
21
63°
45°
22
68°
52°
23
74°
54°
24
73°
57°
25
75°
56°
26
75°
54°
27
78°
55°
28
75°
55°
29
76°
51°
30
77°
57°
31
76°
56°
1
75°
56°
2
76°
57°
3
76°
55°
4
70°
54°
5
70°
53°
6
73°
57°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Mount Vernon
Mount Vernon's May 2026 forecast shows daily high temperatures ranging from 63° to 89°, with overnight lows between 45° and 66°. The average high for May is 75° with an average low of 55°. 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 Mount Vernon. See also: June | July | August.
