S
M
T
W
T
F
S
31
75°
56°
1
74°
55°
2
70°
54°
3
73°
55°
4
76°
58°
5
77°
59°
6
76°
58°
7
73°
57°
8
69°
56°
9
70°
59°
10
76°
61°
11
78°
60°
12
77°
58°
13
71°
55°
14
70°
57°
15
71°
56°
16
71°
54°
17
72°
61°
18
75°
60°
19
75°
54°
20
76°
56°
21
80°
56°
22
82°
62°
23
83°
55°
24
79°
56°
25
75°
57°
26
75°
58°
27
76°
63°
28
80°
56°
29
80°
64°
30
82°
57°
1
77°
56°
2
77°
55°
3
78°
57°
4
78°
57°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
June Weather in St. Catharines
St. Catharines's June 2026 forecast shows daily high temperatures ranging from 69° to 83°, with overnight lows between 54° and 64°. The average high for June is 76° with an average low of 57°. 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 St. Catharines. See also: July | August | September.