S
M
T
W
T
F
S
30
69°
36°
31
72°
39°
1
73°
39°
2
76°
41°
3
77°
43°
4
79°
46°
5
80°
44°
6
79°
37°
7
76°
43°
8
77°
41°
9
66°
35°
10
64°
36°
11
66°
42°
12
71°
41°
13
67°
44°
14
65°
33°
15
63°
36°
16
71°
31°
17
70°
36°
18
71°
34°
19
Hist. Avg.
68°
34°
20
Hist. Avg.
68°
34°
21
Hist. Avg.
68°
34°
22
Hist. Avg.
67°
33°
23
Hist. Avg.
67°
33°
24
Hist. Avg.
66°
33°
25
Hist. Avg.
66°
33°
26
Hist. Avg.
66°
32°
27
Hist. Avg.
65°
32°
28
Hist. Avg.
65°
32°
29
Hist. Avg.
64°
32°
30
Hist. Avg.
64°
31°
1
Hist. Avg.
64°
31°
2
Hist. Avg.
63°
31°
3
Hist. Avg.
63°
31°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Ketchum
Ketchum's September 2026 forecast shows daily high temperatures ranging from 63° to 80°, with overnight lows between 31° and 46°. The average high for September is 72° with an average low of 39°. 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 Ketchum. See also: October | November | December.
