S
M
T
W
T
F
S
26
89°
68°
27
88°
71°
28
89°
72°
29
89°
71°
30
88°
71°
31
88°
70°
1
87°
70°
2
88°
71°
3
88°
71°
4
89°
70°
5
88°
69°
6
86°
68°
7
88°
71°
8
89°
65°
9
81°
64°
10
81°
63°
11
82°
67°
12
82°
69°
13
83°
69°
14
82°
70°
15
84°
70°
16
86°
66°
17
84°
63°
18
82°
62°
19
82°
66°
20
83°
67°
21
85°
68°
22
86°
66°
23
85°
67°
24
85°
62°
25
79°
62°
26
80°
61°
27
78°
61°
28
78°
62°
29
79°
61°
30
79°
63°
31
82°
67°
1
84°
67°
2
84°
66°
3
85°
60°
4
83°
58°
5
77°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Old Westbury
Old Westbury's August 2026 forecast shows daily high temperatures ranging from 77° to 89°, with overnight lows between 58° and 72°. The average high for August is 84° with an average low of 66°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how August weather will actually feel in Old Westbury. See also: September | October | November.