S
M
T
W
T
F
S
29
52°
41°
30
52°
40°
1
51°
40°
2
52°
39°
3
51°
40°
4
50°
38°
5
51°
39°
6
50°
40°
7
49°
37°
8
48°
39°
9
48°
39°
10
49°
38°
11
52°
40°
12
51°
41°
13
Hist. Avg.
48°
39°
14
Hist. Avg.
48°
39°
15
Hist. Avg.
48°
39°
16
Hist. Avg.
48°
39°
17
Hist. Avg.
48°
39°
18
Hist. Avg.
48°
39°
19
Hist. Avg.
48°
39°
20
Hist. Avg.
48°
39°
21
Hist. Avg.
48°
39°
22
Hist. Avg.
48°
39°
23
Hist. Avg.
47°
39°
24
Hist. Avg.
47°
38°
25
Hist. Avg.
47°
38°
26
Hist. Avg.
47°
38°
27
Hist. Avg.
47°
38°
28
Hist. Avg.
47°
38°
29
Hist. Avg.
47°
38°
30
Hist. Avg.
47°
38°
31
Hist. Avg.
47°
38°
1
Hist. Avg.
46°
38°
2
Hist. Avg.
46°
37°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
December Weather in Glastonbury
Glastonbury's December 2026 forecast shows daily high temperatures ranging from 48° to 52°, with overnight lows between 37° and 41°. The average high for December is 50° with an average low of 39°. 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 Glastonbury. See also: January | February | March.
