S
M
T
W
T
F
S
26
79°
66°
27
79°
70°
28
78°
70°
29
81°
68°
30
81°
69°
31
82°
68°
1
81°
69°
2
83°
69°
3
82°
68°
4
82°
70°
5
83°
71°
6
85°
72°
7
86°
68°
8
80°
71°
9
82°
71°
10
81°
71°
11
81°
71°
12
79°
72°
13
79°
71°
14
83°
71°
15
81°
69°
16
79°
69°
17
78°
68°
18
78°
69°
19
80°
70°
20
80°
70°
21
79°
69°
22
78°
69°
23
79°
70°
24
82°
63°
25
75°
62°
26
75°
69°
27
79°
70°
28
82°
70°
29
82°
69°
30
81°
66°
31
76°
61°
1
74°
61°
2
73°
60°
3
73°
60°
4
74°
61°
5
75°
67°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Islip
Islip's August 2026 forecast shows daily high temperatures ranging from 73° to 86°, with overnight lows between 60° and 72°. The average high for August is 80° with an average low of 68°. 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 Islip. See also: September | October | November.
