S
M
T
W
T
F
S
30
72°
49°
31
71°
50°
1
72°
52°
2
72°
52°
3
74°
55°
4
74°
53°
5
73°
49°
6
70°
49°
7
70°
50°
8
71°
51°
9
73°
51°
10
75°
52°
11
75°
53°
12
74°
48°
13
70°
48°
14
69°
53°
15
68°
49°
16
69°
53°
17
72°
53°
18
73°
52°
19
72°
53°
20
73°
53°
21
74°
48°
22
67°
46°
23
67°
46°
24
66°
48°
25
66°
49°
26
68°
48°
27
67°
46°
28
66°
48°
29
65°
47°
30
70°
49°
1
69°
48°
2
69°
50°
3
70°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Rennes
Rennes's September 2026 forecast shows daily high temperatures ranging from 65° to 75°, with overnight lows between 46° and 55°. The average high for September is 70° 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 Rennes. See also: October | November | December.
