S
M
T
W
T
F
S
29
80°
64°
30
80°
62°
1
81°
61°
2
79°
63°
3
80°
54°
4
81°
54°
5
77°
60°
6
73°
61°
7
76°
57°
8
79°
53°
9
78°
54°
10
70°
53°
11
70°
52°
12
71°
52°
13
69°
53°
14
70°
55°
15
70°
59°
16
74°
59°
17
77°
58°
18
76°
53°
19
78°
53°
20
71°
50°
21
70°
49°
22
69°
50°
23
69°
57°
24
73°
51°
25
76°
49°
26
71°
51°
27
69°
58°
28
75°
57°
29
77°
56°
30
75°
56°
31
Hist. Avg.
74°
54°
1
Hist. Avg.
74°
54°
2
Hist. Avg.
74°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
December Weather in Sebastian
Sebastian's December 2026 forecast shows daily high temperatures ranging from 69° to 81°, with overnight lows between 49° and 64°. The average high for December is 75° with an average low of 55°. 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 Sebastian. See also: January | February | March.