S
M
T
W
T
F
S
26
55°
43°
27
58°
44°
28
52°
43°
29
50°
45°
30
56°
46°
1
65°
47°
2
55°
48°
3
55°
44°
4
73°
46°
5
79°
50°
6
70°
57°
7
65°
50°
8
62°
47°
9
55°
42°
10
75°
51°
11
62°
49°
12
64°
48°
13
64°
46°
14
63°
51°
15
55°
50°
16
80°
49°
17
90°
59°
18
71°
59°
19
96°
68°
20
91°
65°
21
73°
57°
22
59°
50°
23
61°
52°
24
55°
52°
25
74°
56°
26
82°
63°
27
84°
60°
28
71°
54°
29
62°
47°
30
56°
50°
31
65°
53°
1
69°
50°
2
68°
56°
3
75°
59°
4
76°
61°
5
79°
60°
6
78°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Downtown Boston
Downtown Boston's May 2026 forecast shows daily high temperatures ranging from 56° to 84°, with overnight lows between 47° and 63°. The average high for May is 72° with an average low of 56°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how May weather will actually feel in Downtown Boston. See also: June | July | August.
