S
M
T
W
T
F
S
30
77°
67°
31
88°
68°
1
89°
69°
2
78°
65°
3
76°
64°
4
76°
64°
5
77°
63°
6
75°
61°
7
75°
59°
8
73°
63°
9
75°
61°
10
71°
58°
11
68°
52°
12
66°
52°
13
67°
54°
14
69°
51°
15
73°
58°
16
73°
57°
17
72°
56°
18
71°
57°
19
72°
57°
20
72°
56°
21
71°
58°
22
73°
57°
23
73°
56°
24
71°
56°
25
72°
55°
26
71°
54°
27
72°
55°
28
72°
54°
29
69°
53°
30
68°
53°
1
69°
54°
2
69°
53°
3
68°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Luxemburg
Luxemburg's September 2026 forecast shows daily high temperatures ranging from 66° to 89°, with overnight lows between 51° and 69°. The average high for September is 72° with an average low of 57°. 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 Luxemburg. See also: October | November | December.