S
M
T
W
T
F
S
30
77°
55°
31
78°
54°
1
79°
55°
2
77°
54°
3
76°
53°
4
77°
54°
5
78°
58°
6
76°
57°
7
76°
56°
8
80°
52°
9
76°
57°
10
79°
61°
11
81°
59°
12
82°
58°
13
82°
50°
14
76°
57°
15
75°
52°
16
75°
54°
17
73°
56°
18
79°
51°
19
76°
54°
20
74°
47°
21
79°
46°
22
70°
44°
23
73°
54°
24
78°
55°
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 70° to 82°, with overnight lows between 44° and 61°. 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.
