S
M
T
W
T
F
S
30
73°
49°
31
84°
45°
1
86°
59°
2
74°
51°
3
73°
49°
4
74°
48°
5
80°
51°
6
79°
54°
7
73°
52°
8
72°
52°
9
78°
53°
10
78°
50°
11
80°
52°
12
80°
51°
13
79°
54°
14
65°
41°
15
83°
55°
16
84°
54°
17
72°
49°
18
74°
49°
19
79°
52°
20
80°
53°
21
75°
51°
22
79°
52°
23
80°
53°
24
79°
47°
25
65°
42°
26
74°
51°
27
75°
50°
28
66°
46°
29
70°
47°
30
75°
49°
1
75°
49°
2
68°
46°
3
62°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Twin Falls
Twin Falls's September 2026 forecast shows daily high temperatures ranging from 62° to 86°, with overnight lows between 41° and 59°. The average high for September is 75° with an average low of 50°. 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 Twin Falls. See also: October | November | December.
