S
M
T
W
T
F
S
30
88°
66°
31
93°
66°
1
88°
66°
2
93°
66°
3
91°
72°
4
90°
68°
5
91°
66°
6
91°
73°
7
88°
72°
8
82°
68°
9
76°
61°
10
81°
62°
11
81°
64°
12
83°
68°
13
82°
68°
14
84°
69°
15
83°
70°
16
82°
67°
17
79°
67°
18
78°
65°
19
77°
66°
20
75°
55°
21
77°
57°
22
78°
57°
23
78°
60°
24
77°
60°
25
78°
59°
26
78°
60°
27
77°
59°
28
77°
60°
29
76°
60°
30
77°
59°
1
76°
57°
2
75°
58°
3
74°
60°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Castries
Castries's September 2026 forecast shows daily high temperatures ranging from 74° to 88°, with overnight lows between 55° and 72°. The average high for September is 79° with an average low of 63°. 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 Castries. See also: October | November | December.
