S
M
T
W
T
F
S
30
90°
74°
31
90°
75°
1
93°
73°
2
91°
74°
3
90°
75°
4
87°
74°
5
89°
76°
6
90°
74°
7
92°
76°
8
91°
74°
9
90°
73°
10
92°
75°
11
89°
73°
12
88°
74°
13
89°
73°
14
87°
70°
15
82°
73°
16
83°
72°
17
83°
72°
18
84°
71°
19
82°
72°
20
81°
72°
21
82°
71°
22
82°
71°
23
83°
70°
24
83°
71°
25
85°
71°
26
85°
69°
27
87°
70°
28
87°
69°
29
86°
68°
30
86°
70°
1
82°
69°
2
81°
69°
3
82°
68°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Slidell
Slidell's September 2026 forecast shows daily high temperatures ranging from 81° to 93°, with overnight lows between 68° and 76°. The average high for September is 86° with an average low of 72°. 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 Slidell. See also: October | November | December.
