S
M
T
W
T
F
S
30
90°
71°
31
90°
70°
1
92°
71°
2
95°
72°
3
97°
74°
4
93°
73°
5
94°
69°
6
88°
71°
7
96°
69°
8
90°
72°
9
83°
62°
10
85°
57°
11
90°
68°
12
76°
57°
13
63°
59°
14
89°
59°
15
73°
57°
16
68°
58°
17
81°
65°
18
99°
70°
19
74°
65°
20
65°
61°
21
74°
59°
22
71°
56°
23
72°
57°
24
64°
59°
25
65°
61°
26
79°
63°
27
81°
62°
28
75°
63°
29
74°
66°
30
71°
67°
1
69°
48°
2
70°
45°
3
77°
49°
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 ° to °, with overnight lows between ° and °. The average high for September is ° with an average low of °. 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.
