S
M
T
W
T
F
S
29
46°
33°
30
48°
35°
1
50°
34°
2
49°
34°
3
51°
32°
4
48°
31°
5
48°
31°
6
46°
32°
7
49°
31°
8
42°
28°
9
39°
28°
10
39°
26°
11
38°
29°
12
38°
26°
13
40°
25°
14
40°
18°
15
35°
19°
16
34°
22°
17
35°
21°
18
34°
27°
19
42°
26°
20
44°
22°
21
38°
20°
22
34°
19°
23
33°
17°
24
35°
23°
25
37°
18°
26
42°
12°
27
33°
13°
28
28°
14°
29
32°
13°
30
31°
18°
31
33°
24°
1
45°
18°
2
42°
13°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Grafton
Grafton's December 2026 forecast shows daily high temperatures ranging from 28° to 51°, with overnight lows between 12° and 35°. The average high for December is 40° 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 Grafton. See also: January | February | March.