S
M
T
W
T
F
S
29
44°
36°
30
47°
40°
1
49°
39°
2
49°
36°
3
43°
34°
4
43°
32°
5
42°
33°
6
42°
32°
7
43°
36°
8
48°
37°
9
46°
38°
10
48°
38°
11
48°
40°
12
47°
38°
13
48°
37°
14
46°
36°
15
48°
32°
16
45°
32°
17
42°
33°
18
42°
32°
19
43°
33°
20
42°
36°
21
45°
39°
22
49°
38°
23
49°
38°
24
48°
37°
25
48°
37°
26
47°
38°
27
46°
36°
28
47°
37°
29
46°
36°
30
47°
39°
31
48°
38°
1
49°
36°
2
47°
35°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Arnside
Arnside's December 2026 forecast shows daily high temperatures ranging from 42° to 49°, with overnight lows between 32° and 40°. The average high for December is 46° with an average low of 36°. 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 Arnside. See also: January | February | March.