S
M
T
W
T
F
S
29
42°
29°
30
40°
34°
1
41°
32°
2
42°
33°
3
43°
31°
4
32°
26°
5
35°
29°
6
49°
27°
7
40°
23°
8
39°
19°
9
33°
20°
10
31°
17°
11
30°
17°
12
31°
19°
13
30°
21°
14
32°
27°
15
36°
25°
16
39°
26°
17
43°
20°
18
44°
20°
19
30°
17°
20
31°
15°
21
30°
16°
22
28°
15°
23
29°
18°
24
30°
23°
25
34°
27°
26
40°
31°
27
44°
27°
28
45°
26°
29
41°
25°
30
39°
24°
31
37°
23°
1
39°
19°
2
34°
21°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Boylston
Boylston's December 2026 forecast shows daily high temperatures ranging from 28° to 49°, with overnight lows between 15° and 34°. The average high for December is 37° with an average low of 23°. 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 Boylston. See also: January | February | March.