S
M
T
W
T
F
S
26
85°
56°
27
84°
64°
28
82°
67°
29
81°
67°
30
81°
68°
31
89°
65°
1
87°
65°
2
86°
73°
3
87°
72°
4
88°
62°
5
84°
68°
6
91°
74°
7
90°
71°
8
87°
69°
9
90°
70°
10
85°
64°
11
86°
69°
12
87°
70°
13
87°
70°
14
87°
69°
15
89°
67°
16
78°
68°
17
88°
66°
18
86°
60°
19
88°
67°
20
82°
60°
21
81°
58°
22
77°
58°
23
79°
57°
24
81°
60°
25
88°
61°
26
86°
62°
27
84°
60°
28
81°
59°
29
80°
56°
30
85°
62°
31
77°
55°
1
78°
55°
2
78°
56°
3
79°
60°
4
78°
57°
5
79°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Collegeville
Collegeville's August 2026 forecast shows daily high temperatures ranging from 77° to 89°, with overnight lows between 55° and 68°. The average high for August is 82° with an average low of 60°. 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 Collegeville. See also: September | October | November.