S
M
T
W
T
F
S
30
90°
74°
31
90°
75°
1
93°
74°
2
91°
73°
3
93°
73°
4
86°
74°
5
87°
75°
6
92°
73°
7
92°
75°
8
91°
73°
9
90°
73°
10
80°
75°
11
89°
75°
12
91°
73°
13
91°
72°
14
92°
73°
15
94°
74°
16
88°
72°
17
90°
68°
18
91°
70°
19
92°
72°
20
91°
74°
21
91°
72°
22
88°
70°
23
87°
69°
24
88°
68°
25
87°
67°
26
85°
68°
27
87°
67°
28
84°
66°
29
84°
69°
30
83°
70°
1
83°
70°
2
84°
69°
3
86°
69°
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 83° to 94°, with overnight lows between 66° and 74°. The average high for September is 88° with an average low of 70°. 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.
