S
M
T
W
T
F
S
28
66°
54°
29
63°
55°
30
63°
54°
1
68°
52°
2
67°
56°
3
71°
53°
4
69°
48°
5
74°
48°
6
71°
52°
7
71°
53°
8
70°
52°
9
71°
53°
10
69°
52°
11
70°
52°
12
73°
54°
13
74°
54°
14
73°
53°
15
70°
58°
16
70°
58°
17
68°
54°
18
72°
55°
19
77°
58°
20
76°
57°
21
76°
58°
22
74°
57°
23
76°
58°
24
70°
58°
25
72°
57°
26
77°
59°
27
77°
58°
28
79°
58°
29
77°
56°
30
78°
58°
31
80°
59°
1
79°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
July Weather in Mount Vernon
Mount Vernon's July 2026 forecast shows daily high temperatures ranging from 67° to 80°, with overnight lows between 48° and 59°. The average high for July is 73° 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 July weather will actually feel in Mount Vernon. See also: August | September | October.