S
M
T
W
T
F
S
30
85°
56°
31
83°
53°
1
77°
50°
2
74°
45°
3
75°
45°
4
74°
54°
5
78°
47°
6
79°
47°
7
83°
47°
8
91°
48°
9
95°
57°
10
93°
61°
11
92°
63°
12
87°
55°
13
79°
51°
14
80°
47°
15
79°
47°
16
75°
47°
17
64°
34°
18
71°
39°
19
76°
44°
20
73°
43°
21
74°
43°
22
77°
46°
23
80°
48°
24
78°
48°
25
77°
46°
26
75°
47°
27
73°
46°
28
72°
44°
29
71°
42°
30
70°
42°
1
73°
45°
2
70°
45°
3
73°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Twain Harte-Tuolumne City
Twain Harte-Tuolumne City's September 2026 forecast shows daily high temperatures ranging from 64° to 80°, with overnight lows between 34° and 48°. The average high for September is 73° with an average low of 44°. 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 Twain Harte-Tuolumne City. See also: October | November | December.