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Current
Hourly
7 Days
14 Days
Weekend
Monthly
Precipitation
Temperature
Wind
Temperature Unit Selection
°Celsius
°Fahrenheit
Monthly Historical Averages
Sarnia, ON
Exceptional El Niño dominates this fall
Content continues below
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
11
12
13
14
15
16
17
18
20°
19
21°
20
19°
21
16°
22
18°
23
16°
24
17°
25
17°
26
19°
27
20°
28
19°
29
20°
30
20°
Forecast
Friday, September 18, 2026
Day
20°
Feels 21
Wind
29 km/h N
Gust
44 km/h
Humidity
60%
P.O.P
20%
Night
14°
Feels 12
Wind
28 km/h N
Gust
42 km/h
Humidity
68%
P.O.P
30%
Historical Averages
Sep 18
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.
September
Average Temperature
High
22°
Feels 23
Low
13°
Feels 12
Average Precipitation
9 Days
Rain amount
36.6mm
Snow amount
0.1cm