Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

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

Mostly Cloudy

80°F

27°C

Humidity 37%
Wind Speed NE 8 G 18 mph
Barometer 30.04 in (1017.1 mb)
Dewpoint 51°F (11°C)
Visibility 10.00 mi
Heat Index80°F (27°C)
Last update 30 Sep 2:56 pm EDT
Detailed forecast for

Southwest Suffolk

This Afternoon
Partly sunny. Near steady temperature in the upper 70s. Northeast winds around 10 mph with gusts up to 20 mph.
Tonight
Partly cloudy. Lows in the mid 50s. Northeast winds 15 to 20 mph with gusts up to 30 mph.
Wednesday
Sunny. Highs in the upper 60s. Northeast winds 15 to 20 mph with gusts up to 35 mph.
Wednesday Night
Clear. Lows in the lower 50s. Northeast winds 10 to 15 mph with gusts up to 25 mph.
Thursday
Sunny. Highs in the mid 60s. Northeast winds 10 to 15 mph with gusts up to 25 mph.
Thursday Night
Partly cloudy in the evening, then becoming mostly cloudy. Lows in the lower 50s.
Friday
Sunny. Highs around 70.
Friday Night
Clear. Lows in the mid 50s.
Saturday
Sunny. Highs in the mid 70s.
Saturday Night
Clear. Lows in the upper 50s.
Sunday
Sunny. Highs in the mid 70s.
Sunday Night
Mostly clear. Lows around 60.
Monday
Sunny. Highs in the mid 70s.
Monday Night
Partly cloudy. Lows in the lower 60s.
Tuesday
Partly sunny. Highs in the mid 70s.



Basemap Options
Click map to change the forecast location
Loading map...
141 PM EDT Tue Sep 30 2025
 
 

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database