S
M
T
W
T
F
S
30
80°
48°
31
69°
51°
1
73°
51°
2
70°
52°
3
71°
46°
4
66°
48°
5
70°
52°
6
76°
43°
7
77°
41°
8
66°
41°
9
62°
43°
10
63°
40°
11
62°
41°
12
64°
41°
13
65°
47°
14
69°
50°
15
69°
49°
16
73°
45°
17
64°
44°
18
61°
47°
19
64°
47°
20
69°
46°
21
65°
40°
22
66°
37°
23
58°
39°
24
60°
43°
25
68°
45°
26
68°
45°
27
Hist. Avg.
64°
34°
28
Hist. Avg.
64°
34°
29
Hist. Avg.
63°
33°
30
Hist. Avg.
63°
33°
1
Hist. Avg.
62°
33°
2
Hist. Avg.
62°
32°
3
Hist. Avg.
62°
32°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Rainier
Rainier's September 2026 forecast shows daily high temperatures ranging from 58° to 80°, with overnight lows between 37° and 52°. The average high for September is 67° with an average low of 45°. 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 Rainier. See also: October | November | December.
