S
M
T
W
T
F
S
30
91°
66°
31
94°
71°
1
97°
73°
2
99°
79°
3
100°
75°
4
99°
72°
5
98°
71°
6
92°
63°
7
90°
63°
8
94°
72°
9
96°
70°
10
90°
67°
11
84°
64°
12
90°
66°
13
93°
68°
14
85°
62°
15
86°
62°
16
87°
61°
17
83°
60°
18
80°
60°
19
76°
61°
20
79°
60°
21
82°
60°
22
82°
59°
23
81°
57°
24
80°
58°
25
79°
59°
26
78°
54°
27
71°
49°
28
70°
46°
29
68°
46°
30
71°
48°
1
70°
50°
2
72°
54°
3
68°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Herrin
Herrin's September 2026 forecast shows daily high temperatures ranging from 68° to 99°, with overnight lows between 46° and 72°. The average high for September is 82° with an average low of 60°. 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 Herrin. See also: October | November | December.
