S
M
T
W
T
F
S
30
83°
58°
31
86°
65°
1
89°
72°
2
92°
70°
3
87°
67°
4
80°
64°
5
79°
59°
6
77°
55°
7
81°
54°
8
84°
67°
9
87°
70°
10
74°
57°
11
79°
54°
12
83°
65°
13
82°
59°
14
78°
64°
15
80°
61°
16
74°
56°
17
72°
57°
18
69°
50°
19
66°
48°
20
71°
50°
21
67°
49°
22
72°
54°
23
71°
53°
24
76°
53°
25
77°
54°
26
77°
53°
27
75°
52°
28
76°
53°
29
77°
54°
30
77°
53°
1
76°
52°
2
74°
47°
3
72°
44°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Prospect
Prospect's September 2026 forecast shows daily high temperatures ranging from 66° to 87°, with overnight lows between 44° and 70°. The average high for September is 76° 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 September weather will actually feel in Prospect. See also: October | November | December.
