S
M
T
W
T
F
S
29
38°
24°
30
36°
23°
1
36°
22°
2
35°
22°
3
36°
25°
4
40°
23°
5
40°
24°
6
39°
28°
7
35°
30°
8
36°
30°
9
37°
24°
10
33°
22°
11
45°
27°
12
44°
28°
13
34°
25°
14
40°
23°
15
38°
15°
16
35°
18°
17
31°
23°
18
34°
23°
19
38°
20°
20
35°
27°
21
35°
27°
22
41°
26°
23
41°
28°
24
40°
29°
25
43°
21°
26
43°
20°
27
42°
17°
28
29°
19°
29
29°
24°
30
39°
24°
31
40°
26°
1
40°
27°
2
42°
25°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Williamstown
Williamstown's December 2026 forecast shows daily high temperatures ranging from 29° to 45°, with overnight lows between 15° and 30°. The average high for December is 38° 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 Williamstown. See also: January | February | March.
