S
M
T
W
T
F
S
30
77°
56°
31
82°
61°
1
82°
61°
2
80°
59°
3
75°
54°
4
74°
52°
5
73°
51°
6
73°
51°
7
75°
58°
8
80°
52°
9
72°
50°
10
72°
51°
11
73°
46°
12
70°
49°
13
70°
48°
14
68°
47°
15
70°
48°
16
71°
49°
17
70°
50°
18
72°
47°
19
70°
46°
20
69°
45°
21
67°
44°
22
68°
45°
23
71°
49°
24
75°
44°
25
74°
50°
26
75°
51°
27
66°
50°
28
68°
46°
29
71°
43°
30
70°
42°
1
65°
46°
2
71°
51°
3
71°
40°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Lehigh Valley
Lehigh Valley's September 2026 forecast shows daily high temperatures ranging from 65° to 82°, with overnight lows between 40° and 61°. The average high for September is 72° with an average low of 49°. 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.
