S
M
T
W
T
F
S
28
81°
58°
29
86°
59°
30
92°
69°
1
94°
71°
2
91°
71°
3
91°
72°
4
79°
69°
5
79°
66°
6
79°
65°
7
77°
65°
8
81°
70°
9
86°
70°
10
78°
67°
11
78°
59°
12
78°
60°
13
79°
60°
14
81°
61°
15
77°
62°
16
78°
61°
17
77°
62°
18
80°
61°
19
79°
60°
20
75°
56°
21
73°
56°
22
74°
57°
23
74°
56°
24
75°
59°
25
78°
63°
26
77°
63°
27
77°
62°
28
78°
64°
29
80°
64°
30
75°
63°
31
77°
64°
1
78°
63°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
July Weather in Ontario on the Lake
Ontario on the Lake's July 2026 forecast shows daily high temperatures ranging from 73° to 86°, with overnight lows between 56° and 70°. The average high for July is 78° with an average low of 62°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how July weather will actually feel in Ontario on the Lake. See also: August | September | October.
