S
M
T
W
T
F
S
26
83°
65°
27
87°
68°
28
87°
69°
29
82°
68°
30
88°
65°
31
83°
61°
1
82°
62°
2
83°
62°
3
84°
66°
4
88°
68°
5
88°
68°
6
89°
66°
7
85°
66°
8
88°
66°
9
88°
66°
10
87°
59°
11
82°
60°
12
83°
61°
13
82°
60°
14
85°
60°
15
82°
62°
16
81°
66°
17
81°
65°
18
82°
62°
19
81°
60°
20
81°
59°
21
82°
64°
22
83°
65°
23
82°
63°
24
86°
64°
25
86°
57°
26
85°
57°
27
80°
58°
28
79°
59°
29
78°
61°
30
79°
62°
31
80°
63°
1
84°
57°
2
79°
57°
3
79°
58°
4
78°
56°
5
78°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Lehigh Valley
Lehigh Valley's August 2026 forecast shows daily high temperatures ranging from 78° to 89°, with overnight lows between 55° and 69°. The average high for August is 83° with an average low of 62°. 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 Lehigh Valley. See also: September | October | November.