S
M
T
W
T
F
S
26
84°
74°
27
83°
74°
28
83°
74°
29
83°
75°
30
83°
73°
1
83°
74°
2
87°
77°
3
81°
73°
4
82°
76°
5
82°
77°
6
86°
79°
7
87°
78°
8
85°
77°
9
86°
78°
10
87°
77°
11
87°
79°
12
84°
77°
13
85°
78°
14
86°
79°
15
85°
81°
16
84°
77°
17
85°
76°
18
85°
78°
19
86°
78°
20
86°
77°
21
87°
79°
22
86°
78°
23
86°
76°
24
87°
79°
25
86°
79°
26
86°
78°
27
88°
79°
28
87°
79°
29
86°
78°
30
87°
79°
31
86°
78°
1
86°
79°
2
87°
80°
3
87°
79°
4
88°
79°
5
88°
80°
6
87°
78°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Marathon
Marathon's May 2026 forecast shows daily high temperatures ranging from 81° to 88°, with overnight lows between 73° and 81°. The average high for May is 86° with an average low of 78°. 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 Marathon. See also: June | July | August.
