S
M
T
W
T
F
S
26
81°
62°
27
82°
61°
28
81°
62°
29
82°
60°
30
81°
61°
31
77°
58°
1
76°
54°
2
76°
56°
3
77°
59°
4
77°
58°
5
79°
60°
6
82°
61°
7
83°
61°
8
82°
60°
9
83°
60°
10
82°
59°
11
83°
60°
12
84°
60°
13
83°
61°
14
85°
51°
15
76°
54°
16
77°
53°
17
76°
52°
18
81°
52°
19
80°
50°
20
75°
49°
21
75°
50°
22
76°
51°
23
74°
49°
24
75°
53°
25
78°
56°
26
75°
56°
27
81°
50°
28
83°
48°
29
74°
48°
30
72°
49°
31
73°
48°
1
72°
46°
2
71°
47°
3
73°
47°
4
72°
48°
5
73°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Black River Falls
Black River Falls's August 2026 forecast shows daily high temperatures ranging from 71° to 85°, with overnight lows between 46° and 62°. The average high for August is 78° with an average low of 55°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how August weather will actually feel in Black River Falls. See also: September | October | November.