S
M
T
W
T
F
S
30
74°
57°
31
76°
55°
1
76°
60°
2
76°
59°
3
80°
65°
4
76°
64°
5
69°
57°
6
73°
56°
7
80°
63°
8
73°
60°
9
71°
59°
10
72°
55°
11
66°
51°
12
75°
53°
13
78°
63°
14
66°
49°
15
65°
48°
16
77°
61°
17
70°
58°
18
67°
51°
19
62°
47°
20
64°
51°
21
61°
43°
22
63°
44°
23
66°
45°
24
67°
48°
25
71°
53°
26
71°
51°
27
66°
51°
28
68°
53°
29
70°
55°
30
67°
53°
1
64°
52°
2
67°
49°
3
58°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in LaSalle
LaSalle's September 2026 forecast shows daily high temperatures ranging from 58° to 71°, with overnight lows between 43° and 55°. The average high for September is 66° with an average low of 50°. 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 LaSalle. See also: October | November | December.
