S
M
T
W
T
F
S
30
90°
80°
31
89°
80°
1
88°
79°
2
88°
79°
3
89°
80°
4
90°
79°
5
89°
78°
6
88°
79°
7
88°
80°
8
89°
80°
9
89°
79°
10
88°
79°
11
89°
80°
12
89°
79°
13
88°
80°
14
89°
79°
15
89°
80°
16
88°
79°
17
89°
80°
18
90°
79°
19
89°
80°
20
90°
79°
21
89°
79°
22
89°
78°
23
88°
79°
24
89°
78°
25
89°
78°
26
88°
79°
27
88°
78°
28
89°
78°
29
88°
79°
30
89°
78°
1
88°
79°
2
89°
78°
3
88°
77°
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 88° to 90°, with overnight lows between 77° and 80°. The average high for September is 89° with an average low of 79°. 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.
