S
M
T
W
T
F
S
29
42°
30°
30
41°
30°
1
42°
37°
2
47°
39°
3
47°
34°
4
45°
32°
5
47°
30°
6
48°
30°
7
47°
32°
8
47°
37°
9
48°
35°
10
46°
29°
11
46°
29°
12
45°
30°
13
48°
36°
14
43°
35°
15
51°
34°
16
47°
39°
17
46°
38°
18
47°
36°
19
49°
37°
20
47°
36°
21
46°
38°
22
47°
37°
23
47°
34°
24
45°
30°
25
46°
28°
26
45°
28°
27
39°
27°
28
38°
30°
29
39°
27°
30
40°
32°
31
42°
38°
1
46°
33°
2
46°
31°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Rainier
Rainier's December 2026 forecast shows daily high temperatures ranging from 38° to 51°, with overnight lows between 27° and 39°. The average high for December is 45° with an average low of 33°. 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 Rainier. See also: January | February | March.
