S
M
T
W
T
F
S
29
47°
34°
30
49°
35°
1
51°
36°
2
50°
34°
3
51°
33°
4
46°
29°
5
49°
29°
6
49°
32°
7
48°
31°
8
41°
27°
9
39°
24°
10
38°
23°
11
36°
30°
12
39°
28°
13
40°
27°
14
36°
22°
15
39°
22°
16
39°
26°
17
40°
27°
18
38°
28°
19
45°
26°
20
42°
16°
21
37°
18°
22
34°
20°
23
32°
23°
24
36°
22°
25
41°
21°
26
40°
16°
27
34°
13°
28
31°
12°
29
32°
9°
30
33°
25°
31
40°
23°
1
47°
17°
2
39°
16°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Lehigh Valley
Lehigh Valley's December 2026 forecast shows daily high temperatures ranging from 31° to 51°, with overnight lows between 9° and 36°. The average high for December is 41° with an average low of 24°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how December weather will actually feel in Lehigh Valley. See also: January | February | March.
