S
M
T
W
T
F
S
30
71°
49°
31
64°
48°
1
69°
49°
2
69°
47°
3
68°
48°
4
69°
49°
5
70°
43°
6
64°
37°
7
58°
36°
8
58°
36°
9
59°
37°
10
58°
37°
11
61°
38°
12
65°
39°
13
66°
41°
14
65°
42°
15
63°
36°
16
58°
34°
17
57°
34°
18
56°
40°
19
62°
40°
20
65°
43°
21
64°
42°
22
59°
33°
23
54°
39°
24
52°
36°
25
53°
41°
26
56°
40°
27
58°
40°
28
51°
37°
29
51°
36°
30
52°
39°
1
50°
38°
2
54°
28°
3
49°
27°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Triangle
Triangle's September 2026 forecast shows daily high temperatures ranging from 49° to 71°, with overnight lows between 27° and 49°. The average high for September is 60° with an average low of 39°. 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 Triangle. See also: October | November | December.
