S
M
T
W
T
F
S
30
83°
55°
31
82°
60°
1
82°
60°
2
83°
61°
3
83°
61°
4
82°
60°
5
80°
55°
6
79°
59°
7
80°
59°
8
80°
58°
9
81°
58°
10
80°
57°
11
81°
58°
12
81°
58°
13
80°
60°
14
81°
60°
15
79°
58°
16
79°
57°
17
76°
58°
18
77°
50°
19
76°
45°
20
67°
52°
21
69°
50°
22
70°
45°
23
66°
46°
24
67°
52°
25
72°
55°
26
69°
55°
27
66°
52°
28
67°
52°
29
67°
54°
30
66°
54°
1
64°
51°
2
64°
44°
3
63°
43°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Niagara-on-the-Lake
Niagara-on-the-Lake's September 2026 forecast shows daily high temperatures ranging from 63° to 83°, with overnight lows between 43° and 61°. The average high for September is 75° with an average low of 55°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Niagara-on-the-Lake. See also: October | November | December.
