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°Fahrenheit
Monthly Historical Averages
Thornbury, ON
Your 2026 Fall Forecast is here!
Content continues below
September
Average Temperature
High
20°
Feels 21
Low
12°
Feels 11
Average Precipitation
8 Days
Rain amount
34.7mm
Snow amount
0cm
Content continues below
Daily Historical Averages
September 2026
S
M
T
W
T
F
S
1
2
3
4
5
6
7
8
9
10
21°
11
21°
12
25°
13
21°
14
18°
15
20°
16
20°
17
19°
18
17°
19
16°
20
17°
21
17°
22
18°
23
18°
24
19°
25
26
27
28
29
30
Forecast
Thursday, September 10, 2026
Day
21°
Feels 22
Wind
35 km/h W
Gust
53 km/h
Humidity
60%
P.O.P
30%
Night
12°
Feels 10
Wind
32 km/h W
Gust
48 km/h
Humidity
88%
P.O.P
30%
Historical Averages
Sep 10
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.