S
M
T
W
T
F
S
30
74°
50°
31
73°
49°
1
73°
50°
2
74°
51°
3
72°
51°
4
70°
50°
5
74°
51°
6
73°
50°
7
71°
48°
8
70°
46°
9
70°
49°
10
71°
50°
11
69°
46°
12
69°
46°
13
71°
46°
14
72°
53°
15
72°
52°
16
74°
52°
17
74°
45°
18
70°
44°
19
72°
49°
20
73°
47°
21
67°
44°
22
68°
48°
23
69°
49°
24
70°
50°
25
71°
48°
26
70°
41°
27
69°
41°
28
62°
42°
29
61°
42°
30
61°
40°
1
Hist. Avg.
65°
43°
2
Hist. Avg.
65°
43°
3
Hist. Avg.
64°
43°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Northwest Ithaca
Northwest Ithaca's September 2026 forecast shows daily high temperatures ranging from 61° to 74°, with overnight lows between 40° and 53°. The average high for September is 70° with an average low of 48°. 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 Northwest Ithaca. See also: October | November | December.
