Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79° N Lon: 73.1° W Elev: 98 ft.

Mostly Cloudy

77°F

25°C

Humidity 77%
Wind Speed S 12 G 23 mph
Barometer 30.11 in (1019.4 mb)
Dewpoint 69°F (21°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 9 Sep 3:56 pm EDT
Detailed forecast for

Northwest Suffolk

Tonight
Mostly cloudy. Lows in the lower 70s. Southwest winds 15 to 20 mph with gusts up to 30 mph.
Thursday
Partly sunny. A slight chance of showers in the morning. Humid with highs in the mid 80s. West winds 10 to 15 mph with gusts up to 25 mph. Chance of rain 20 percent.
Thursday Night
Partly cloudy in the evening, then becoming mostly cloudy. Lows in the mid 60s. Northwest winds 5 to 10 mph.
Friday
Sunny. Highs in the mid 70s. Northwest winds 5 to 10 mph.
Friday Night
Mostly clear. Lows in the upper 50s. North winds around 5 mph.
Saturday
Mostly sunny. Highs in the mid 70s.
Saturday Night
Mostly cloudy. A chance of showers after midnight. Lows in the mid 60s. Chance of rain 50 percent.
Sunday
Mostly cloudy. A chance of showers. Highs in the upper 70s. Chance of rain 50 percent.
Sunday Night
Mostly cloudy. Lows in the mid 60s.
Monday
Mostly sunny. Highs in the upper 70s.
Monday Night
Partly cloudy. Lows in the lower 60s.
Tuesday
Mostly sunny. Highs in the upper 70s.
Tuesday Night
Partly cloudy. Lows in the upper 60s.
Wednesday
Mostly sunny. Highs in the lower 80s.



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333 PM EDT Wed Sep 9 2026
 
 

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database