S
M
T
W
T
F
S
26
67°
26°
27
74°
29°
28
67°
30°
29
66°
30°
30
51°
41°
1
53°
28°
2
49°
28°
3
46°
27°
4
64°
27°
5
80°
32°
6
57°
43°
7
55°
30°
8
50°
27°
9
57°
25°
10
63°
36°
11
56°
28°
12
51°
26°
13
50°
28°
14
56°
44°
15
65°
50°
16
75°
50°
17
76°
47°
18
81°
40°
19
83°
49°
20
79°
48°
21
59°
32°
22
66°
26°
23
68°
30°
24
54°
46°
25
62°
44°
26
80°
38°
27
75°
45°
28
64°
48°
29
60°
44°
30
57°
34°
31
64°
47°
1
60°
43°
2
64°
41°
3
69°
44°
4
75°
48°
5
77°
53°
6
73°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Northumberland
Northumberland's May 2026 forecast shows daily high temperatures ranging from 57° to 77°, with overnight lows between 34° and 53°. The average high for May is 66° with an average low of 46°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how May weather will actually feel in Northumberland. See also: June | July | August.