S
M
T
W
T
F
S
29
69°
52°
30
64°
51°
1
65°
50°
2
64°
51°
3
63°
50°
4
65°
51°
5
64°
50°
6
68°
50°
7
69°
49°
8
67°
51°
9
62°
50°
10
63°
49°
11
62°
41°
12
61°
42°
13
62°
46°
14
65°
45°
15
68°
47°
16
67°
45°
17
63°
49°
18
65°
49°
19
65°
52°
20
66°
51°
21
68°
42°
22
66°
41°
23
63°
40°
24
61°
42°
25
62°
46°
26
64°
46°
27
67°
45°
28
63°
45°
29
63°
43°
30
62°
42°
31
61°
42°
1
62°
43°
2
62°
43°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in National City
National City's December 2026 forecast shows daily high temperatures ranging from 61° to 69°, with overnight lows between 40° and 52°. The average high for December is 64° with an average low of 47°. 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 National City. See also: January | February | March.