S
M
T
W
T
F
S
30
76°
60°
31
77°
59°
1
71°
64°
2
70°
64°
3
83°
64°
4
83°
60°
5
76°
59°
6
73°
52°
7
80°
49°
8
79°
52°
9
76°
69°
10
80°
58°
11
74°
48°
12
77°
63°
13
79°
59°
14
77°
57°
15
78°
66°
16
77°
56°
17
72°
57°
18
73°
57°
19
67°
49°
20
68°
51°
21
70°
50°
22
69°
50°
23
68°
54°
24
69°
54°
25
64°
44°
26
65°
47°
27
66°
53°
28
68°
49°
29
63°
44°
30
64°
51°
1
65°
50°
2
62°
46°
3
67°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Rensselaer
Rensselaer's September 2026 forecast shows daily high temperatures ranging from 62° to 80°, with overnight lows between 44° and 69°. The average high for September is 70° with an average low of 53°. 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 Rensselaer. See also: October | November | December.
