S
M
T
W
T
F
S
26
59°
33°
27
72°
32°
28
66°
53°
29
60°
44°
30
49°
36°
1
53°
32°
2
47°
37°
3
55°
34°
4
74°
45°
5
72°
46°
6
47°
41°
7
53°
33°
8
54°
35°
9
65°
35°
10
55°
35°
11
53°
31°
12
57°
29°
13
69°
43°
14
51°
41°
15
62°
42°
16
77°
38°
17
77°
56°
18
89°
60°
19
88°
60°
20
66°
42°
21
57°
38°
22
65°
52°
23
55°
48°
24
61°
49°
25
65°
55°
26
74°
54°
27
70°
53°
28
72°
53°
29
73°
52°
30
76°
55°
31
77°
59°
1
72°
51°
2
69°
55°
3
69°
55°
4
71°
54°
5
69°
55°
6
72°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Port Byron
Port Byron's May 2026 forecast shows daily high temperatures ranging from 55° to 88°, with overnight lows between 38° and 60°. The average high for May is 70° with an average low of 52°. 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 Port Byron. See also: June | July | August.
