S
M
T
W
T
F
S
31
77°
65°
1
85°
66°
2
81°
56°
3
82°
52°
4
85°
55°
5
86°
68°
6
86°
71°
7
87°
71°
8
86°
69°
9
93°
75°
10
92°
74°
11
91°
70°
12
84°
64°
13
78°
63°
14
78°
58°
15
78°
55°
16
81°
55°
17
92°
58°
18
78°
60°
19
84°
57°
20
85°
65°
21
84°
66°
22
71°
60°
23
82°
57°
24
84°
61°
25
87°
70°
26
79°
70°
27
85°
71°
28
95°
75°
29
96°
73°
30
97°
73°
1
96°
76°
2
93°
72°
3
95°
72°
4
92°
71°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
June Weather in O'Fallon
O'Fallon's June 2026 forecast shows daily high temperatures ranging from 92° to 97°, with overnight lows between 71° and 76°. The average high for June is 95° with an average low of 73°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how June weather will actually feel in O'Fallon. See also: July | August | September.
