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7 Days
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Monthly
Precipitation
Temperature
Wind
Temperature Unit Selection
°Celsius
°Fahrenheit
Monthly Historical Averages
Sullivan, IL
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Daily Historical Averages
October 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
19
20
21
23°
22
23°
23
22°
24
22°
25
24°
26
23°
27
21°
28
21°
29
17°
30
14°
31
15°
Forecast
Wednesday, October 21, 2026
Day
23°
Feels 23
Wind
3 km/h NE
Gust
5 km/h
Humidity
31%
P.O.P
0%
Night
10°
Feels 10
Wind
4 km/h S
Gust
7 km/h
Humidity
75%
P.O.P
0%
Historical Averages
Oct 21
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.
October
Average Temperature
High
19°
Feels 19
Low
8°
Feels 6
Average Precipitation
9 Days
Rain amount
64.9mm
Snow amount
0.1cm