S
M
T
W
T
F
S
26
61°
39°
27
72°
36°
28
64°
36°
29
63°
48°
30
61°
46°
1
64°
39°
2
59°
45°
3
61°
43°
4
73°
37°
5
82°
45°
6
68°
54°
7
64°
45°
8
63°
39°
9
63°
46°
10
73°
48°
11
63°
45°
12
68°
39°
13
73°
46°
14
66°
48°
15
69°
49°
16
82°
64°
17
88°
62°
18
83°
64°
19
98°
69°
20
88°
59°
21
69°
53°
22
67°
55°
23
71°
54°
24
72°
58°
25
73°
61°
26
78°
62°
27
80°
63°
28
79°
56°
29
69°
55°
30
70°
61°
31
78°
58°
1
71°
56°
2
72°
55°
3
71°
55°
4
72°
56°
5
73°
61°
6
78°
63°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Mountainside
Mountainside's May 2026 forecast shows daily high temperatures ranging from 67° to 98°, with overnight lows between 49° and 69°. The average high for May is 76° with an average low of 59°. 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 Mountainside. See also: June | July | August.
