S
M
T
W
T
F
S
29
43°
33°
30
41°
32°
1
41°
32°
2
40°
31°
3
41°
33°
4
42°
36°
5
43°
34°
6
42°
38°
7
43°
38°
8
45°
37°
9
43°
31°
10
38°
32°
11
49°
34°
12
48°
34°
13
41°
33°
14
49°
32°
15
45°
28°
16
39°
25°
17
36°
31°
18
37°
32°
19
42°
32°
20
42°
33°
21
41°
34°
22
46°
33°
23
47°
34°
24
46°
37°
25
49°
27°
26
50°
25°
27
48°
23°
28
34°
26°
29
33°
31°
30
42°
31°
31
44°
32°
1
45°
34°
2
47°
31°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Boston
Boston's December 2026 forecast shows daily high temperatures ranging from 33° to 50°, with overnight lows between 23° and 38°. The average high for December is 43° with an average low of 32°. 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 Boston. See also: January | February | March.
