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