S
M
T
W
T
F
S
29
44°
32°
30
47°
32°
1
46°
34°
2
45°
35°
3
43°
39°
4
49°
38°
5
49°
35°
6
48°
38°
7
49°
38°
8
48°
37°
9
49°
38°
10
49°
37°
11
47°
40°
12
50°
36°
13
51°
37°
14
48°
38°
15
47°
39°
16
49°
40°
17
50°
38°
18
50°
37°
19
49°
34°
20
50°
31°
21
43°
36°
22
45°
32°
23
47°
31°
24
42°
32°
25
42°
31°
26
43°
34°
27
42°
36°
28
45°
37°
29
48°
29°
30
47°
30°
31
42°
30°
1
42°
31°
2
43°
30°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Chelmsford
Chelmsford's December 2026 forecast shows daily high temperatures ranging from 42° to 51°, with overnight lows between 29° and 40°. The average high for December is 47° with an average low of 35°. 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 Chelmsford. See also: January | February | March.
