S
M
T
W
T
F
S
30
81°
64°
31
80°
61°
1
81°
60°
2
79°
59°
3
77°
64°
4
84°
66°
5
82°
61°
6
76°
59°
7
77°
59°
8
77°
60°
9
82°
63°
10
81°
59°
11
76°
63°
12
75°
62°
13
77°
63°
14
80°
62°
15
82°
64°
16
82°
64°
17
79°
63°
18
82°
63°
19
81°
64°
20
82°
64°
21
78°
63°
22
77°
63°
23
76°
62°
24
73°
62°
25
74°
61°
26
79°
62°
27
80°
53°
28
69°
50°
29
68°
50°
30
69°
58°
1
78°
53°
2
70°
48°
3
72°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in McLean
McLean's September 2026 forecast shows daily high temperatures ranging from 68° to 84°, with overnight lows between 44° and 66°. The average high for September is 78° with an average low of 60°. 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 McLean. See also: October | November | December.
