S
M
T
W
T
F
S
29
46°
37°
30
45°
36°
1
47°
34°
2
46°
37°
3
45°
39°
4
47°
38°
5
46°
37°
6
45°
36°
7
44°
33°
8
44°
33°
9
43°
39°
10
45°
42°
11
51°
40°
12
50°
37°
13
49°
34°
14
47°
39°
15
47°
39°
16
51°
40°
17
46°
42°
18
50°
42°
19
51°
40°
20
50°
36°
21
48°
32°
22
43°
38°
23
45°
35°
24
48°
33°
25
43°
34°
26
45°
38°
27
44°
35°
28
Hist. Avg.
46°
37°
29
Hist. Avg.
46°
37°
30
Hist. Avg.
47°
37°
31
Hist. Avg.
47°
37°
1
Hist. Avg.
47°
37°
2
Hist. Avg.
47°
37°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
December Weather in Seattle
Seattle's December 2026 forecast shows daily high temperatures ranging from 43° to 51°, with overnight lows between 32° and 42°. The average high for December is 47° with an average low of 37°. 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 Seattle. See also: January | February | March.
