S
M
T
W
T
F
S
30
77°
54°
31
80°
58°
1
82°
59°
2
82°
57°
3
81°
54°
4
81°
59°
5
80°
57°
6
78°
57°
7
75°
56°
8
73°
57°
9
77°
51°
10
74°
50°
11
73°
57°
12
78°
53°
13
79°
56°
14
75°
55°
15
77°
55°
16
77°
56°
17
Hist. Avg.
77°
55°
18
Hist. Avg.
77°
54°
19
Hist. Avg.
76°
54°
20
Hist. Avg.
76°
54°
21
Hist. Avg.
76°
53°
22
Hist. Avg.
75°
53°
23
Hist. Avg.
75°
52°
24
Hist. Avg.
74°
52°
25
Hist. Avg.
74°
52°
26
Hist. Avg.
74°
51°
27
Hist. Avg.
73°
51°
28
Hist. Avg.
73°
51°
29
Hist. Avg.
72°
50°
30
Hist. Avg.
72°
50°
1
Hist. Avg.
71°
49°
2
Hist. Avg.
71°
49°
3
Hist. Avg.
71°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Lehigh Valley
Lehigh Valley's September 2026 forecast shows daily high temperatures ranging from 73° to 82°, with overnight lows between 50° and 59°. The average high for September is 78° with an average low of 56°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Lehigh Valley. See also: October | November | December.
