S
M
T
W
T
F
S
26
81°
60°
27
82°
62°
28
72°
56°
29
74°
51°
30
81°
56°
31
84°
60°
1
80°
58°
2
79°
56°
3
81°
55°
4
84°
59°
5
79°
58°
6
77°
56°
7
79°
56°
8
80°
53°
9
74°
57°
10
79°
58°
11
77°
57°
12
78°
59°
13
79°
57°
14
74°
57°
15
76°
56°
16
78°
57°
17
78°
56°
18
73°
55°
19
72°
56°
20
76°
55°
21
71°
55°
22
73°
56°
23
76°
51°
24
74°
48°
25
68°
53°
26
73°
56°
27
77°
55°
28
75°
56°
29
75°
53°
30
67°
50°
31
66°
47°
1
66°
50°
2
65°
47°
3
68°
50°
4
72°
53°
5
74°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Mattawa
Mattawa's August 2026 forecast shows daily high temperatures ranging from 65° to 84°, with overnight lows between 47° and 62°. The average high for August is 75° with an average low of 55°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how August weather will actually feel in Mattawa. See also: September | October | November.