S
M
T
W
T
F
S
30
87°
81°
31
84°
84°
1
88°
79°
2
91°
84°
3
90°
86°
4
90°
84°
5
90°
82°
6
88°
82°
7
88°
86°
8
90°
84°
9
91°
84°
10
91°
84°
11
93°
90°
12
91°
82°
13
91°
84°
14
90°
82°
15
90°
84°
16
91°
86°
17
86°
82°
18
90°
81°
19
90°
80°
20
90°
80°
21
89°
80°
22
90°
80°
23
90°
80°
24
89°
81°
25
90°
79°
26
89°
78°
27
90°
79°
28
90°
80°
29
86°
81°
30
87°
80°
1
87°
80°
2
86°
81°
3
86°
81°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in St Thomas
St Thomas's September 2026 forecast shows daily high temperatures ranging from 86° to 90°, with overnight lows between 78° and 81°. The average high for September is 89° with an average low of 80°. 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 St Thomas. See also: October | November | December.
