S
M
T
W
T
F
S
30
88°
74°
31
91°
75°
1
91°
73°
2
92°
75°
3
90°
73°
4
86°
74°
5
89°
73°
6
93°
73°
7
91°
75°
8
92°
74°
9
91°
72°
10
92°
71°
11
90°
69°
12
89°
70°
13
90°
69°
14
94°
75°
15
86°
72°
16
84°
72°
17
84°
71°
18
85°
72°
19
83°
72°
20
83°
71°
21
84°
71°
22
83°
70°
23
86°
70°
24
85°
69°
25
88°
70°
26
87°
69°
27
88°
70°
28
88°
69°
29
87°
68°
30
87°
69°
1
83°
69°
2
82°
68°
3
84°
68°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Winthrop Square
Winthrop Square's September 2026 forecast shows daily high temperatures ranging from 82° to 94°, with overnight lows between 68° and 75°. The average high for September is 87° with an average low of 71°. 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 Winthrop Square. See also: October | November | December.
