S
M
T
W
T
F
S
30
78°
57°
31
82°
60°
1
85°
55°
2
81°
54°
3
78°
53°
4
79°
55°
5
79°
61°
6
83°
60°
7
85°
59°
8
78°
59°
9
76°
60°
10
79°
59°
11
79°
56°
12
78°
58°
13
77°
57°
14
75°
51°
15
74°
51°
16
74°
50°
17
73°
51°
18
73°
55°
19
78°
56°
20
77°
57°
21
78°
53°
22
72°
48°
23
72°
54°
24
71°
55°
25
77°
48°
26
68°
52°
27
74°
53°
28
75°
51°
29
69°
53°
30
Hist. Avg.
71°
47°
1
Hist. Avg.
70°
46°
2
Hist. Avg.
70°
46°
3
Hist. Avg.
70°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Hillsborough
Hillsborough's September 2026 forecast shows daily high temperatures ranging from 68° to 85°, with overnight lows between 48° and 61°. The average high for September is 77° with an average low of 55°. 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 Hillsborough. See also: October | November | December.
