S
M
T
W
T
F
S
29
50°
32°
30
50°
26°
1
46°
28°
2
44°
33°
3
46°
28°
4
45°
27°
5
47°
31°
6
47°
29°
7
46°
25°
8
44°
27°
9
43°
25°
10
41°
24°
11
37°
23°
12
36°
18°
13
39°
13°
14
29°
18°
15
28°
21°
16
38°
13°
17
39°
7°
18
37°
13°
19
24°
22°
20
35°
17°
21
37°
19°
22
29°
22°
23
34°
21°
24
35°
19°
25
33°
21°
26
35°
23°
27
24°
13°
28
27°
6°
29
Hist. Avg.
30°
13°
30
Hist. Avg.
30°
13°
31
Hist. Avg.
29°
13°
1
Hist. Avg.
29°
13°
2
Hist. Avg.
29°
12°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
December Weather in Waterloo
Waterloo's December 2026 forecast shows daily high temperatures ranging from 24° to 50°, with overnight lows between 6° and 33°. The average high for December is 38° with an average low of 21°. 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 Waterloo. See also: January | February | March.
