S
M
T
W
T
F
S
30
96°
75°
31
97°
74°
1
99°
68°
2
99°
71°
3
97°
72°
4
97°
73°
5
100°
70°
6
96°
73°
7
87°
71°
8
97°
73°
9
88°
69°
10
86°
61°
11
86°
67°
12
85°
64°
13
85°
68°
14
86°
61°
15
76°
56°
16
75°
55°
17
74°
53°
18
72°
52°
19
73°
53°
20
72°
52°
21
77°
54°
22
81°
60°
23
81°
61°
24
82°
61°
25
82°
60°
26
81°
61°
27
81°
60°
28
80°
60°
29
79°
59°
30
77°
57°
1
77°
52°
2
66°
47°
3
66°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Sumner
Sumner's September 2026 forecast shows daily high temperatures ranging from 66° to 97°, with overnight lows between 45° and 73°. The average high for September is 79° with an average low of 59°. 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 Sumner. See also: October | November | December.
