S
M
T
W
T
F
S
26
79°
54°
27
82°
55°
28
59°
47°
29
65°
43°
30
67°
40°
1
68°
42°
2
66°
40°
3
82°
42°
4
82°
55°
5
58°
47°
6
57°
39°
7
67°
45°
8
79°
50°
9
80°
58°
10
72°
49°
11
76°
56°
12
80°
57°
13
81°
60°
14
81°
59°
15
83°
61°
16
82°
63°
17
83°
57°
18
78°
61°
19
78°
59°
20
74°
56°
21
79°
53°
22
72°
53°
23
72°
55°
24
70°
56°
25
72°
55°
26
73°
54°
27
75°
59°
28
76°
60°
29
76°
61°
30
77°
65°
31
78°
62°
1
77°
58°
2
78°
61°
3
78°
66°
4
80°
66°
5
79°
66°
6
79°
67°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Dennis
Dennis's May 2026 forecast shows daily high temperatures ranging from 57° to 83°, with overnight lows between 39° and 67°. The average high for May is 76° with an average low of 57°. 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 Dennis. See also: June | July | August.