S
M
T
W
T
F
S
30
72°
49°
31
73°
48°
1
72°
46°
2
71°
47°
3
73°
47°
4
72°
48°
5
73°
49°
6
70°
47°
7
70°
47°
8
72°
51°
9
72°
44°
10
70°
43°
11
71°
47°
12
73°
50°
13
70°
43°
14
68°
51°
15
72°
52°
16
77°
52°
17
74°
49°
18
75°
41°
19
67°
40°
20
65°
40°
21
64°
41°
22
67°
47°
23
70°
47°
24
66°
43°
25
66°
38°
26
65°
37°
27
63°
38°
28
61°
37°
29
61°
37°
30
61°
35°
1
Hist. Avg.
65°
39°
2
Hist. Avg.
64°
39°
3
Hist. Avg.
64°
38°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Black River Falls
Black River Falls's September 2026 forecast shows daily high temperatures ranging from 61° to 77°, with overnight lows between 35° and 52°. The average high for September is 69° with an average low of 45°. 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 Black River Falls. See also: October | November | December.
