S
M
T
W
T
F
S
30
80°
56°
31
79°
56°
1
69°
60°
2
74°
61°
3
76°
61°
4
81°
63°
5
73°
58°
6
73°
51°
7
80°
54°
8
80°
55°
9
79°
55°
10
85°
64°
11
77°
51°
12
77°
46°
13
69°
62°
14
72°
47°
15
71°
43°
16
80°
49°
17
79°
61°
18
78°
57°
19
66°
43°
20
57°
49°
21
67°
49°
22
63°
43°
23
62°
42°
24
63°
47°
25
62°
51°
26
65°
50°
27
71°
46°
28
69°
47°
29
70°
47°
30
72°
49°
1
70°
47°
2
69°
43°
3
65°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Harvard
Harvard's September 2026 forecast shows daily high temperatures ranging from 62° to 72°, with overnight lows between 42° and 51°. The average high for September is 67° with an average low of 47°. 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 Harvard. See also: October | November | December.
