S
M
T
W
T
F
S
26
86°
65°
27
86°
65°
28
86°
64°
29
83°
65°
30
83°
64°
31
86°
66°
1
86°
66°
2
84°
65°
3
87°
65°
4
87°
65°
5
86°
62°
6
80°
63°
7
84°
59°
8
79°
58°
9
78°
58°
10
78°
57°
11
80°
63°
12
86°
64°
13
86°
63°
14
85°
57°
15
79°
57°
16
79°
63°
17
81°
63°
18
79°
57°
19
78°
57°
20
80°
56°
21
81°
57°
22
84°
57°
23
83°
56°
24
83°
58°
25
82°
61°
26
83°
62°
27
84°
61°
28
83°
60°
29
84°
62°
30
84°
55°
31
78°
52°
1
76°
52°
2
75°
53°
3
75°
52°
4
76°
52°
5
74°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Herndon
Herndon's August 2026 forecast shows daily high temperatures ranging from 74° to 87°, with overnight lows between 52° and 66°. The average high for August is 82° with an average low of 60°. 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 Herndon. See also: September | October | November.
