S
M
T
W
T
F
S
29
43°
27°
30
44°
26°
1
44°
28°
2
42°
22°
3
41°
21°
4
40°
25°
5
40°
30°
6
45°
36°
7
52°
31°
8
57°
28°
9
55°
26°
10
39°
23°
11
40°
24°
12
44°
24°
13
41°
26°
14
40°
24°
15
37°
21°
16
37°
21°
17
38°
22°
18
37°
27°
19
38°
30°
20
40°
33°
21
51°
26°
22
52°
26°
23
42°
32°
24
48°
30°
25
52°
29°
26
47°
29°
27
43°
20°
28
46°
17°
29
35°
16°
30
36°
12°
31
35°
11°
1
29°
13°
2
32°
15°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Lowell
Lowell's December 2026 forecast shows daily high temperatures ranging from 29° to 57°, with overnight lows between 11° and 36°. The average high for December is 42° 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 Lowell. See also: January | February | March.