S
M
T
W
T
F
S
30
90°
71°
31
90°
71°
1
94°
68°
2
94°
70°
3
95°
69°
4
94°
71°
5
94°
69°
6
93°
69°
7
88°
68°
8
88°
66°
9
89°
67°
10
90°
66°
11
87°
66°
12
89°
65°
13
88°
64°
14
88°
65°
15
82°
60°
16
79°
63°
17
80°
62°
18
76°
63°
19
77°
63°
20
79°
62°
21
80°
63°
22
80°
62°
23
83°
61°
24
82°
62°
25
77°
62°
26
80°
61°
27
80°
54°
28
74°
51°
29
73°
50°
30
75°
50°
1
74°
53°
2
75°
57°
3
73°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Cornwall Furnace
Cornwall Furnace's September 2026 forecast shows daily high temperatures ranging from 73° to 95°, with overnight lows between 50° and 71°. The average high for September is 83° with an average low of 62°. 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 Cornwall Furnace. See also: October | November | December.
