S
M
T
W
T
F
S
30
68°
55°
31
71°
54°
1
71°
54°
2
70°
51°
3
68°
52°
4
70°
53°
5
69°
49°
6
69°
52°
7
67°
51°
8
69°
52°
9
66°
51°
10
65°
50°
11
65°
48°
12
64°
50°
13
64°
48°
14
65°
52°
15
65°
52°
16
67°
51°
17
65°
52°
18
66°
48°
19
67°
47°
20
62°
49°
21
64°
50°
22
64°
46°
23
62°
46°
24
61°
50°
25
63°
51°
26
64°
50°
27
65°
45°
28
63°
45°
29
61°
44°
30
61°
44°
1
60°
43°
2
61°
45°
3
62°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Mark
Mark's September 2026 forecast shows daily high temperatures ranging from 60° to 71°, with overnight lows between 43° and 55°. The average high for September is 65° with an average low of 49°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Mark. See also: October | November | December.