S
M
T
W
T
F
S
30
82°
66°
31
81°
59°
1
79°
58°
2
74°
59°
3
73°
59°
4
74°
58°
5
73°
58°
6
73°
57°
7
74°
57°
8
73°
58°
9
73°
61°
10
72°
57°
11
74°
59°
12
74°
59°
13
77°
58°
14
75°
59°
15
72°
56°
16
71°
56°
17
68°
55°
18
70°
57°
19
69°
55°
20
73°
61°
21
73°
53°
22
68°
52°
23
Hist. Avg.
70°
56°
24
Hist. Avg.
70°
55°
25
Hist. Avg.
70°
55°
26
Hist. Avg.
69°
55°
27
Hist. Avg.
69°
54°
28
Hist. Avg.
69°
54°
29
Hist. Avg.
68°
53°
30
Hist. Avg.
68°
53°
1
Hist. Avg.
67°
53°
2
Hist. Avg.
67°
52°
3
Hist. Avg.
67°
52°
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 68° to 82°, with overnight lows between 52° and 66°. The average high for September is 74° with an average low of 58°. 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.
