S
M
T
W
T
F
S
26
85°
70°
27
88°
74°
28
85°
71°
29
73°
60°
30
64°
58°
1
63°
53°
2
76°
49°
3
82°
49°
4
81°
55°
5
87°
68°
6
68°
54°
7
71°
50°
8
80°
53°
9
85°
64°
10
80°
64°
11
79°
61°
12
82°
50°
13
87°
51°
14
88°
61°
15
89°
64°
16
88°
69°
17
89°
73°
18
89°
78°
19
86°
64°
20
79°
62°
21
76°
66°
22
85°
67°
23
83°
65°
24
86°
64°
25
88°
64°
26
88°
64°
27
83°
66°
28
87°
68°
29
90°
68°
30
90°
69°
31
93°
73°
1
94°
71°
2
94°
68°
3
90°
67°
4
88°
69°
5
85°
72°
6
85°
73°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Marietta
Marietta's May 2026 forecast shows daily high temperatures ranging from 85° to 94°, with overnight lows between 67° and 73°. The average high for May is 90° with an average low of 70°. 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 Marietta. See also: June | July | August.