S
M
T
W
T
F
S
30
89°
74°
31
89°
73°
1
90°
72°
2
90°
74°
3
87°
75°
4
91°
74°
5
94°
72°
6
91°
74°
7
87°
73°
8
91°
72°
9
92°
73°
10
94°
70°
11
91°
72°
12
87°
70°
13
90°
70°
14
88°
71°
15
88°
74°
16
87°
73°
17
87°
73°
18
84°
72°
19
84°
73°
20
82°
72°
21
82°
72°
22
83°
71°
23
82°
72°
24
81°
71°
25
80°
71°
26
82°
70°
27
81°
71°
28
83°
71°
29
84°
70°
30
80°
70°
1
80°
69°
2
81°
70°
3
80°
69°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Darien
Darien's September 2026 forecast shows daily high temperatures ranging from 80° to 94°, with overnight lows between 69° and 75°. The average high for September is 86° with an average low of 72°. 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 Darien. See also: October | November | December.
