S
M
T
W
T
F
S
26
82°
66°
27
86°
63°
28
85°
68°
29
85°
65°
30
77°
66°
1
64°
52°
2
73°
45°
3
75°
45°
4
79°
52°
5
80°
65°
6
83°
67°
7
80°
56°
8
77°
58°
9
75°
61°
10
82°
66°
11
84°
65°
12
86°
63°
13
84°
63°
14
83°
62°
15
84°
66°
16
85°
65°
17
86°
66°
18
85°
66°
19
84°
67°
20
85°
67°
21
86°
66°
22
85°
67°
23
82°
67°
24
83°
66°
25
84°
68°
26
81°
68°
27
82°
67°
28
84°
68°
29
85°
68°
30
86°
67°
31
87°
68°
1
87°
69°
2
88°
69°
3
89°
70°
4
90°
70°
5
86°
67°
6
85°
69°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Smithtown
Smithtown's May 2026 forecast shows daily high temperatures ranging from 64° to 90°, with overnight lows between 45° and 70°. The average high for May is 83° with an average low of 64°. 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 Smithtown. See also: June | July | August.
