S
M
T
W
T
F
S
30
66°
56°
31
67°
54°
1
66°
52°
2
66°
55°
3
67°
55°
4
67°
54°
5
66°
53°
6
67°
53°
7
66°
54°
8
64°
53°
9
63°
53°
10
65°
52°
11
66°
51°
12
66°
49°
13
61°
49°
14
61°
48°
15
62°
51°
16
61°
50°
17
65°
51°
18
63°
52°
19
60°
53°
20
64°
52°
21
66°
48°
22
67°
52°
23
67°
53°
24
Hist. Avg.
64°
50°
25
Hist. Avg.
64°
49°
26
Hist. Avg.
64°
49°
27
Hist. Avg.
64°
49°
28
Hist. Avg.
64°
49°
29
Hist. Avg.
63°
49°
30
Hist. Avg.
63°
49°
1
Hist. Avg.
63°
48°
2
Hist. Avg.
63°
48°
3
Hist. Avg.
63°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Eureka
Eureka's September 2026 forecast shows daily high temperatures ranging from 60° to 67°, with overnight lows between 48° and 56°. The average high for September is 65° with an average low of 52°. 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 Eureka. See also: October | November | December.
