S
M
T
W
T
F
S
26
91°
74°
27
94°
73°
28
98°
71°
29
98°
74°
30
93°
69°
31
97°
67°
1
91°
74°
2
83°
73°
3
87°
71°
4
86°
70°
5
89°
70°
6
89°
71°
7
91°
70°
8
90°
71°
9
92°
69°
10
92°
71°
11
91°
70°
12
92°
69°
13
90°
71°
14
91°
70°
15
88°
71°
16
87°
69°
17
92°
72°
18
93°
73°
19
94°
73°
20
94°
72°
21
93°
72°
22
91°
71°
23
91°
72°
24
92°
72°
25
92°
71°
26
91°
72°
27
91°
72°
28
90°
71°
29
90°
70°
30
91°
71°
31
91°
71°
1
90°
72°
2
91°
71°
3
88°
70°
4
84°
67°
5
84°
66°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Johnston
Johnston's August 2026 forecast shows daily high temperatures ranging from 83° to 94°, with overnight lows between 66° and 74°. The average high for August is 90° with an average low of 71°. 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 Johnston. See also: September | October | November.
