S
M
T
W
T
F
S
28
86°
62°
29
87°
60°
30
89°
63°
1
89°
62°
2
87°
62°
3
89°
64°
4
90°
65°
5
91°
64°
6
90°
62°
7
84°
59°
8
83°
59°
9
84°
60°
10
86°
62°
11
89°
63°
12
91°
65°
13
91°
65°
14
90°
64°
15
91°
65°
16
91°
66°
17
90°
65°
18
90°
65°
19
91°
64°
20
91°
66°
21
92°
65°
22
91°
66°
23
92°
65°
24
92°
66°
25
91°
65°
26
91°
66°
27
94°
65°
28
94°
64°
29
89°
63°
30
92°
64°
31
94°
66°
1
93°
65°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
July Weather in Diamond Bar
Diamond Bar's July 2026 forecast shows daily high temperatures ranging from 83° to 94°, with overnight lows between 59° and 66°. The average high for July is 90° with an average low of 64°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how July weather will actually feel in Diamond Bar. See also: August | September | October.
