S
M
T
W
T
F
S
29
48°
32°
30
44°
27°
1
35°
24°
2
32°
16°
3
35°
29°
4
37°
28°
5
36°
27°
6
34°
21°
7
31°
17°
8
29°
18°
9
33°
18°
10
36°
27°
11
38°
27°
12
41°
25°
13
38°
27°
14
34°
26°
15
37°
23°
16
38°
23°
17
35°
19°
18
33°
17°
19
34°
12°
20
28°
9°
21
25°
23°
22
35°
21°
23
36°
19°
24
36°
10°
25
31°
14°
26
28°
23°
27
35°
22°
28
36°
20°
29
33°
10°
30
31°
17°
31
29°
6°
1
31°
2°
2
23°
9°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Johnston
Johnston's December 2026 forecast shows daily high temperatures ranging from 23° to 48°, with overnight lows between 2° and 32°. The average high for December is 34° with an average low of 20°. 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 Johnston. See also: January | February | March.
