S
M
T
W
T
F
S
30
92°
71°
31
92°
70°
1
91°
68°
2
90°
69°
3
90°
69°
4
88°
68°
5
91°
68°
6
90°
69°
7
91°
66°
8
89°
65°
9
86°
65°
10
87°
66°
11
89°
66°
12
89°
67°
13
90°
68°
14
87°
64°
15
86°
64°
16
Hist. Avg.
87°
67°
17
Hist. Avg.
87°
66°
18
Hist. Avg.
87°
66°
19
Hist. Avg.
87°
66°
20
Hist. Avg.
87°
66°
21
Hist. Avg.
87°
65°
22
Hist. Avg.
86°
65°
23
Hist. Avg.
86°
65°
24
Hist. Avg.
86°
64°
25
Hist. Avg.
86°
64°
26
Hist. Avg.
86°
64°
27
Hist. Avg.
86°
63°
28
Hist. Avg.
85°
63°
29
Hist. Avg.
85°
63°
30
Hist. Avg.
85°
62°
1
Hist. Avg.
85°
62°
2
Hist. Avg.
84°
62°
3
Hist. Avg.
84°
61°
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 86° to 92°, with overnight lows between 64° and 71°. The average high for September is 89° with an average low of 67°. 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.
