S
M
T
W
T
F
S
30
70°
63°
31
75°
61°
1
68°
55°
2
73°
52°
3
72°
63°
4
75°
61°
5
68°
57°
6
70°
50°
7
82°
59°
8
77°
63°
9
66°
55°
10
64°
50°
11
70°
48°
12
70°
57°
13
66°
59°
14
68°
55°
15
81°
60°
16
68°
53°
17
67°
56°
18
66°
54°
19
66°
60°
20
66°
52°
21
66°
55°
22
68°
54°
23
69°
53°
24
67°
51°
25
67°
51°
26
66°
50°
27
65°
52°
28
66°
51°
29
67°
51°
30
65°
50°
1
64°
50°
2
64°
50°
3
65°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Letter
Letter's September 2026 forecast shows daily high temperatures ranging from 64° to 81°, with overnight lows between 50° and 60°. The average high for September is 67° 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 Letter. See also: October | November | December.
