S
M
T
W
T
F
S
30
81°
51°
31
79°
46°
1
73°
46°
2
72°
48°
3
72°
46°
4
73°
46°
5
72°
45°
6
71°
45°
7
72°
46°
8
75°
49°
9
73°
50°
10
70°
46°
11
70°
48°
12
73°
46°
13
74°
50°
14
75°
49°
15
69°
44°
16
69°
45°
17
66°
44°
18
68°
47°
19
73°
49°
20
Hist. Avg.
68°
42°
21
Hist. Avg.
68°
42°
22
Hist. Avg.
68°
41°
23
Hist. Avg.
67°
41°
24
Hist. Avg.
67°
40°
25
Hist. Avg.
66°
40°
26
Hist. Avg.
66°
40°
27
Hist. Avg.
66°
39°
28
Hist. Avg.
65°
39°
29
Hist. Avg.
65°
38°
30
Hist. Avg.
64°
38°
1
Hist. Avg.
64°
38°
2
Hist. Avg.
64°
37°
3
Hist. Avg.
63°
37°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Lost River
Lost River's September 2026 forecast shows daily high temperatures ranging from 66° to 81°, with overnight lows between 44° and 51°. The average high for September is 72° with an average low of 47°. 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 Lost River. See also: October | November | December.
