S
M
T
W
T
F
S
26
80°
65°
27
85°
67°
28
79°
66°
29
74°
65°
30
81°
62°
31
78°
63°
1
76°
67°
2
71°
61°
3
79°
61°
4
79°
62°
5
76°
65°
6
80°
69°
7
75°
71°
8
82°
70°
9
80°
65°
10
80°
71°
11
82°
69°
12
77°
67°
13
81°
70°
14
79°
68°
15
74°
67°
16
73°
64°
17
79°
66°
18
78°
66°
19
80°
66°
20
74°
64°
21
79°
62°
22
79°
65°
23
70°
63°
24
71°
61°
25
76°
65°
26
75°
63°
27
80°
67°
28
72°
62°
29
79°
61°
30
71°
67°
31
74°
67°
1
79°
71°
2
82°
69°
3
80°
68°
4
76°
67°
5
76°
67°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in St. Catharines
St. Catharines's August 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for August 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 August weather will actually feel in St. Catharines. See also: September | October | November.
