S
M
T
W
T
F
S
30
90°
60°
31
90°
66°
1
89°
66°
2
90°
65°
3
90°
65°
4
89°
66°
5
90°
66°
6
88°
65°
7
88°
63°
8
82°
64°
9
81°
63°
10
84°
64°
11
87°
63°
12
87°
64°
13
88°
63°
14
87°
62°
15
86°
62°
16
79°
54°
17
78°
54°
18
79°
59°
19
83°
53°
20
77°
52°
21
75°
55°
22
76°
54°
23
77°
58°
24
82°
59°
25
83°
59°
26
83°
58°
27
82°
57°
28
81°
54°
29
80°
53°
30
80°
53°
1
78°
52°
2
81°
56°
3
73°
47°
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 73° to 90°, with overnight lows between 47° and 66°. The average high for September is 83° with an average low of 59°. 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.
