S
M
T
W
T
F
S
30
72°
50°
31
83°
45°
1
82°
50°
2
71°
54°
3
67°
53°
4
66°
46°
5
74°
42°
6
75°
45°
7
66°
53°
8
72°
53°
9
80°
48°
10
80°
54°
11
72°
49°
12
75°
50°
13
61°
48°
14
64°
46°
15
65°
49°
16
75°
46°
17
77°
46°
18
78°
51°
19
79°
46°
20
81°
46°
21
84°
47°
22
78°
50°
23
71°
48°
24
78°
45°
25
62°
49°
26
61°
40°
27
64°
34°
28
69°
45°
29
66°
47°
30
71°
41°
1
73°
45°
2
71°
46°
3
72°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Liberty Lake
Liberty Lake's September 2026 forecast shows daily high temperatures ranging from 64° to 73°, with overnight lows between 34° and 47°. The average high for September is 69° with an average low of 43°. 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 Liberty Lake. See also: October | November | December.
