S
M
T
W
T
F
S
26
65°
40°
27
67°
52°
28
63°
50°
29
56°
36°
30
56°
33°
1
49°
33°
2
55°
28°
3
64°
41°
4
80°
45°
5
56°
45°
6
58°
38°
7
59°
33°
8
65°
42°
9
74°
44°
10
62°
40°
11
55°
40°
12
76°
39°
13
60°
41°
14
64°
35°
15
73°
46°
16
82°
60°
17
86°
63°
18
80°
64°
19
78°
51°
20
56°
44°
21
62°
49°
22
65°
57°
23
67°
55°
24
73°
56°
25
74°
59°
26
75°
60°
27
77°
59°
28
79°
61°
29
76°
60°
30
79°
62°
31
80°
61°
1
76°
55°
2
78°
58°
3
72°
54°
4
71°
52°
5
72°
58°
6
78°
61°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in St. John
St. John's May 2026 forecast shows daily high temperatures ranging from 56° to 80°, with overnight lows between 44° and 62°. The average high for May is 73° with an average low of 56°. 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 St. John. See also: June | July | August.
