S
M
T
W
T
F
S
30
78°
51°
31
88°
46°
1
85°
57°
2
78°
56°
3
68°
50°
4
68°
48°
5
74°
52°
6
75°
56°
7
72°
47°
8
75°
51°
9
77°
56°
10
81°
56°
11
79°
55°
12
77°
53°
13
80°
53°
14
79°
54°
15
83°
57°
16
80°
48°
17
73°
48°
18
73°
44°
19
71°
44°
20
71°
48°
21
77°
52°
22
82°
53°
23
82°
51°
24
70°
42°
25
68°
41°
26
69°
45°
27
75°
49°
28
80°
51°
29
80°
50°
30
79°
51°
1
80°
50°
2
79°
50°
3
80°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Caldwell
Caldwell's September 2026 forecast shows daily high temperatures ranging from 68° to 83°, with overnight lows between 41° and 57°. The average high for September is 76° with an average low of 50°. 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 Caldwell. See also: October | November | December.
