S
M
T
W
T
F
S
29
47°
39°
30
47°
40°
1
48°
40°
2
49°
42°
3
48°
43°
4
50°
43°
5
51°
42°
6
52°
44°
7
52°
44°
8
51°
42°
9
50°
42°
10
51°
43°
11
52°
44°
12
52°
43°
13
51°
44°
14
52°
44°
15
52°
43°
16
51°
43°
17
51°
42°
18
46°
40°
19
46°
41°
20
49°
41°
21
51°
39°
22
48°
39°
23
46°
38°
24
46°
38°
25
47°
39°
26
47°
39°
27
50°
41°
28
49°
41°
29
52°
40°
30
48°
37°
31
47°
39°
1
46°
43°
2
51°
39°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
December Weather in Newcastle
Newcastle's December 2026 forecast shows daily high temperatures ranging from 46° to 52°, with overnight lows between 37° and 44°. The average high for December is 49° with an average low of 41°. 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 Newcastle. See also: January | February | March.
