S
M
T
W
T
F
S
30
76°
58°
31
75°
58°
1
71°
66°
2
75°
61°
3
75°
60°
4
72°
58°
5
70°
57°
6
73°
52°
7
78°
51°
8
75°
62°
9
72°
62°
10
63°
46°
11
72°
42°
12
75°
52°
13
70°
50°
14
63°
46°
15
64°
45°
16
69°
49°
17
73°
49°
18
59°
41°
19
63°
39°
20
60°
44°
21
54°
39°
22
N/A
23
67°
39°
24
70°
33°
25
69°
36°
26
71°
43°
27
72°
44°
28
69°
41°
29
73°
47°
30
69°
49°
1
66°
48°
2
65°
46°
3
64°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Mattawa
Mattawa's September 2026 forecast shows daily high temperatures ranging from 64° to 73°, with overnight lows between 33° and 49°. 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 Mattawa. See also: October | November | December.
