S
M
T
W
T
F
S
30
82°
55°
31
85°
49°
1
74°
50°
2
73°
57°
3
74°
58°
4
81°
48°
5
83°
46°
6
71°
48°
7
72°
55°
8
76°
51°
9
76°
48°
10
71°
54°
11
71°
50°
12
72°
45°
13
69°
45°
14
69°
48°
15
70°
52°
16
69°
55°
17
78°
55°
18
78°
50°
19
77°
49°
20
69°
47°
21
71°
46°
22
69°
45°
23
66°
40°
24
65°
41°
25
66°
42°
26
66°
40°
27
75°
49°
28
76°
49°
29
Hist. Avg.
67°
42°
30
Hist. Avg.
66°
41°
1
Hist. Avg.
66°
41°
2
Hist. Avg.
65°
40°
3
Hist. Avg.
65°
40°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Montevideo
Montevideo's September 2026 forecast shows daily high temperatures ranging from 65° to 85°, with overnight lows between 40° and 58°. The average high for September is 73° with an average low of 49°. 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 Montevideo. See also: October | November | December.