S
M
T
W
T
F
S
30
69°
64°
31
76°
65°
1
84°
69°
2
81°
66°
3
74°
61°
4
71°
61°
5
75°
57°
6
74°
54°
7
73°
54°
8
76°
53°
9
73°
67°
10
73°
51°
11
71°
47°
12
80°
54°
13
71°
60°
14
65°
48°
15
71°
48°
16
70°
55°
17
70°
50°
18
69°
49°
19
65°
49°
20
69°
52°
21
64°
45°
22
66°
42°
23
70°
43°
24
69°
35°
25
69°
39°
26
71°
41°
27
72°
45°
28
72°
47°
29
70°
55°
30
68°
56°
1
69°
54°
2
67°
52°
3
66°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Brussels
Brussels's September 2026 forecast shows daily high temperatures ranging from 66° to 72°, with overnight lows between 35° and 56°. The average high for September is 69° with an average low of 47°. 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 Brussels. See also: October | November | December.
