S
M
T
W
T
F
S
30
88°
54°
31
89°
55°
1
86°
49°
2
87°
51°
3
88°
53°
4
88°
52°
5
83°
52°
6
84°
53°
7
85°
51°
8
83°
49°
9
83°
51°
10
85°
46°
11
85°
47°
12
84°
49°
13
85°
51°
14
86°
51°
15
84°
47°
16
80°
47°
17
79°
48°
18
80°
48°
19
81°
47°
20
82°
46°
21
81°
48°
22
82°
51°
23
82°
51°
24
83°
52°
25
85°
51°
26
84°
52°
27
84°
52°
28
86°
51°
29
86°
51°
30
85°
52°
1
85°
52°
2
84°
51°
3
85°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Atascadero
Atascadero's September 2026 forecast shows daily high temperatures ranging from 79° to 89°, with overnight lows between 46° and 55°. The average high for September is 84° 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 Atascadero. See also: October | November | December.
