S
M
T
W
T
F
S
29
46°
19°
30
44°
18°
1
48°
18°
2
50°
19°
3
48°
20°
4
50°
21°
5
51°
23°
6
52°
24°
7
52°
25°
8
51°
24°
9
50°
21°
10
44°
22°
11
41°
18°
12
47°
21°
13
39°
22°
14
Hist. Avg.
43°
17°
15
Hist. Avg.
42°
16°
16
Hist. Avg.
42°
16°
17
Hist. Avg.
42°
16°
18
Hist. Avg.
42°
16°
19
Hist. Avg.
42°
16°
20
Hist. Avg.
42°
16°
21
Hist. Avg.
42°
16°
22
Hist. Avg.
42°
16°
23
Hist. Avg.
42°
16°
24
Hist. Avg.
42°
16°
25
Hist. Avg.
42°
16°
26
Hist. Avg.
42°
16°
27
Hist. Avg.
42°
16°
28
Hist. Avg.
42°
16°
29
Hist. Avg.
42°
16°
30
Hist. Avg.
42°
17°
31
Hist. Avg.
42°
17°
1
Hist. Avg.
42°
17°
2
Hist. Avg.
42°
17°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
December Weather in Flagstaff
Flagstaff's December 2026 forecast shows daily high temperatures ranging from 39° to 52°, with overnight lows between 18° and 25°. The average high for December is 48° 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 Flagstaff. See also: January | February | March.
