S
M
T
W
T
F
S
30
80°
54°
31
80°
53°
1
72°
54°
2
70°
61°
3
69°
61°
4
85°
62°
5
75°
59°
6
75°
53°
7
83°
49°
8
81°
55°
9
69°
53°
10
85°
64°
11
74°
50°
12
75°
42°
13
67°
53°
14
70°
47°
15
71°
42°
16
82°
50°
17
77°
58°
18
77°
53°
19
68°
44°
20
60°
38°
21
69°
47°
22
65°
42°
23
64°
41°
24
68°
39°
25
69°
43°
26
66°
54°
27
58°
53°
28
55°
53°
29
64°
53°
30
70°
52°
1
75°
57°
2
75°
49°
3
66°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Barrington
Barrington's September 2026 forecast shows daily high temperatures ranging from 55° to 75°, with overnight lows between 46° and 57°. The average high for September is 66° with an average low of 52°. 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 Barrington. See also: October | November | December.