S
M
T
W
T
F
S
30
68°
49°
31
73°
54°
1
76°
57°
2
79°
57°
3
78°
56°
4
68°
46°
5
70°
47°
6
69°
49°
7
74°
50°
8
73°
55°
9
70°
47°
10
70°
46°
11
71°
50°
12
69°
55°
13
68°
46°
14
67°
45°
15
66°
45°
16
67°
46°
17
67°
47°
18
70°
47°
19
75°
49°
20
75°
47°
21
68°
47°
22
68°
48°
23
64°
45°
24
65°
44°
25
62°
41°
26
65°
42°
27
63°
43°
28
65°
50°
29
70°
49°
30
61°
43°
1
72°
53°
2
69°
51°
3
Hist. Avg.
62°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Lowell
Lowell's September 2026 forecast shows daily high temperatures ranging from 61° to 79°, with overnight lows between 41° and 57°. The average high for September is 69° with an average low of 48°. 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 Lowell. See also: October | November | December.
