S
M
T
W
T
F
S
26
75°
59°
27
77°
57°
28
82°
63°
29
90°
61°
30
73°
59°
31
75°
57°
1
77°
52°
2
79°
56°
3
84°
59°
4
83°
61°
5
80°
54°
6
74°
56°
7
78°
58°
8
72°
54°
9
75°
56°
10
76°
58°
11
76°
58°
12
78°
60°
13
76°
57°
14
75°
57°
15
72°
57°
16
73°
56°
17
70°
56°
18
68°
54°
19
68°
51°
20
67°
51°
21
66°
50°
22
67°
50°
23
67°
51°
24
71°
55°
25
72°
56°
26
72°
54°
27
70°
53°
28
70°
55°
29
71°
53°
30
72°
54°
31
72°
55°
1
71°
54°
2
69°
50°
3
65°
49°
4
66°
49°
5
67°
48°
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 65° to 84°, with overnight lows between 48° and 61°. The average high for August is 72° with an average low of 54°. 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.
