S
M
T
W
T
F
S
30
82°
54°
31
78°
53°
1
76°
56°
2
76°
55°
3
77°
55°
4
76°
53°
5
76°
53°
6
74°
57°
7
75°
53°
8
76°
53°
9
76°
52°
10
75°
52°
11
75°
51°
12
74°
51°
13
75°
52°
14
74°
56°
15
77°
57°
16
79°
56°
17
81°
55°
18
80°
52°
19
79°
55°
20
Hist. Avg.
76°
51°
21
Hist. Avg.
75°
50°
22
Hist. Avg.
75°
50°
23
Hist. Avg.
75°
50°
24
Hist. Avg.
74°
49°
25
Hist. Avg.
74°
49°
26
Hist. Avg.
73°
48°
27
Hist. Avg.
73°
48°
28
Hist. Avg.
73°
48°
29
Hist. Avg.
72°
47°
30
Hist. Avg.
72°
47°
1
Hist. Avg.
71°
46°
2
Hist. Avg.
71°
46°
3
Hist. Avg.
70°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in LaSalle
LaSalle's September 2026 forecast shows daily high temperatures ranging from 74° to 82°, with overnight lows between 51° and 57°. The average high for September is 77° with an average low of 54°. 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.
