S
M
T
W
T
F
S
26
79°
59°
27
78°
58°
28
75°
57°
29
70°
56°
30
71°
56°
31
74°
56°
1
78°
58°
2
79°
57°
3
72°
50°
4
72°
50°
5
75°
51°
6
78°
53°
7
72°
52°
8
73°
50°
9
72°
58°
10
79°
60°
11
81°
59°
12
82°
61°
13
82°
59°
14
81°
60°
15
81°
55°
16
80°
50°
17
79°
53°
18
75°
56°
19
71°
52°
20
70°
54°
21
70°
47°
22
69°
46°
23
70°
48°
24
71°
51°
25
75°
55°
26
77°
56°
27
78°
56°
28
79°
58°
29
79°
58°
30
78°
56°
31
78°
55°
1
77°
54°
2
76°
51°
3
74°
51°
4
72°
53°
5
69°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Mount Vernon
Mount Vernon's August 2026 forecast shows daily high temperatures ranging from 69° to 82°, with overnight lows between 45° and 61°. The average high for August is 76° with an average low of 54°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how August weather will actually feel in Mount Vernon. See also: September | October | November.
