S
M
T
W
T
F
S
27
75°
58°
28
82°
55°
29
86°
50°
30
95°
64°
1
93°
71°
2
74°
56°
3
78°
50°
4
83°
48°
5
79°
50°
6
80°
45°
7
89°
48°
8
86°
51°
9
89°
49°
10
83°
51°
11
87°
50°
12
94°
59°
13
95°
62°
14
81°
66°
15
83°
60°
16
61°
50°
17
60°
40°
18
67°
37°
19
73°
38°
20
74°
47°
21
76°
43°
22
79°
46°
23
77°
47°
24
76°
44°
25
80°
46°
26
78°
49°
27
74°
46°
28
80°
46°
29
83°
53°
30
79°
57°
31
75°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
October Weather in O'Fallon
O'Fallon's October 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for October is ° with an average low of °. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how October weather will actually feel in O'Fallon. See also: November | December | January.
