S
M
T
W
T
F
S
30
81°
66°
31
77°
64°
1
77°
57°
2
79°
55°
3
81°
57°
4
90°
68°
5
81°
63°
6
81°
60°
7
90°
64°
8
88°
62°
9
71°
51°
10
71°
51°
11
72°
53°
12
72°
57°
13
73°
56°
14
75°
57°
15
77°
59°
16
69°
54°
17
67°
53°
18
66°
52°
19
65°
48°
20
69°
49°
21
70°
54°
22
71°
53°
23
72°
53°
24
72°
52°
25
71°
53°
26
71°
48°
27
66°
45°
28
68°
46°
29
68°
46°
30
67°
52°
1
66°
46°
2
63°
44°
3
67°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Lachen
Lachen's September 2026 forecast shows daily high temperatures ranging from 63° to 90°, with overnight lows between 44° and 64°. The average high for September is 71° 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 Lachen. See also: October | November | December.
