S
M
T
W
T
F
S
30
69°
38°
31
73°
43°
1
74°
41°
2
71°
38°
3
70°
39°
4
71°
36°
5
70°
46°
6
75°
45°
7
81°
47°
8
81°
46°
9
Hist. Avg.
73°
40°
10
Hist. Avg.
73°
40°
11
Hist. Avg.
72°
40°
12
Hist. Avg.
72°
39°
13
Hist. Avg.
72°
39°
14
Hist. Avg.
71°
39°
15
Hist. Avg.
71°
39°
16
Hist. Avg.
70°
38°
17
Hist. Avg.
70°
38°
18
Hist. Avg.
70°
38°
19
Hist. Avg.
69°
38°
20
Hist. Avg.
69°
37°
21
Hist. Avg.
68°
37°
22
Hist. Avg.
68°
37°
23
Hist. Avg.
67°
36°
24
Hist. Avg.
67°
36°
25
Hist. Avg.
66°
36°
26
Hist. Avg.
66°
35°
27
Hist. Avg.
65°
35°
28
Hist. Avg.
65°
35°
29
Hist. Avg.
64°
34°
30
Hist. Avg.
64°
34°
1
Hist. Avg.
63°
34°
2
Hist. Avg.
62°
33°
3
Hist. Avg.
62°
33°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Columbia Falls
Columbia Falls's September 2026 forecast shows daily high temperatures ranging from 69° to 81°, with overnight lows between 36° and 47°. The average high for September is 74° with an average low of 42°. 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 Columbia Falls. See also: October | November | December.
