S
M
T
W
T
F
S
30
50°
41°
1
54°
41°
2
65°
35°
3
71°
38°
4
55°
37°
5
52°
35°
6
46°
40°
7
50°
42°
8
49°
41°
9
49°
41°
10
48°
42°
11
52°
41°
12
49°
40°
13
48°
39°
14
43°
38°
15
50°
39°
16
58°
40°
17
64°
49°
18
57°
41°
19
59°
53°
20
59°
56°
21
60°
58°
22
58°
55°
23
58°
55°
24
60°
52°
25
59°
49°
26
57°
50°
27
58°
38°
28
59°
36°
29
58°
30°
30
48°
33°
31
49°
41°
1
55°
49°
2
59°
53°
3
62°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Petaluma
Petaluma's December 2025 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for December is ° with an average low of °. 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 Petaluma. See also: January | February | March.
