S
M
T
W
T
F
S
30
77°
57°
31
74°
50°
1
73°
51°
2
73°
48°
3
71°
47°
4
72°
48°
5
74°
51°
6
74°
55°
7
72°
54°
8
73°
54°
9
74°
52°
10
76°
50°
11
76°
55°
12
75°
54°
13
76°
55°
14
77°
53°
15
75°
45°
16
72°
45°
17
68°
51°
18
67°
54°
19
76°
53°
20
73°
47°
21
74°
43°
22
72°
41°
23
72°
49°
24
Hist. Avg.
69°
52°
25
Hist. Avg.
69°
51°
26
Hist. Avg.
68°
51°
27
Hist. Avg.
68°
50°
28
Hist. Avg.
67°
50°
29
Hist. Avg.
67°
50°
30
Hist. Avg.
66°
49°
1
Hist. Avg.
66°
49°
2
Hist. Avg.
66°
49°
3
Hist. Avg.
65°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Boston
Boston's September 2026 forecast shows daily high temperatures ranging from 67° to 77°, with overnight lows between 41° and 57°. The average high for September is 73° 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 Boston. See also: October | November | December.
