National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Fair

29°F

-2°C

Humidity 89%
Wind Speed Calm
Barometer 30.59 in (1035.9 mb)
Dewpoint 26°F (-3°C)
Visibility 10.00 mi
Last update 9 Apr 3:56 am EDT
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Today

    Today: Areas of frost before 9am. Otherwise, sunny, with a high near 49. Light southeast wind becoming south 6 to 11 mph in the morning.

    High: 49 °F

    Areas Frost
    then Sunny

  • Tonight

    Tonight: Patchy fog after 2am. Otherwise, mostly clear, with a low around 37. South wind 5 to 8 mph becoming calm after midnight.

    Low: 37 °F

    Mostly Clear
    then Patchy
    Fog

  • Friday

    Friday: Patchy fog before 8am. Otherwise, partly sunny, with a high near 56. Light southwest wind becoming south 6 to 11 mph in the morning.

    High: 56 °F

    Patchy Fog
    then Mostly
    Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 42. South wind 8 to 10 mph.

    Low: 42 °F

    Mostly Cloudy

  • Saturday

    Saturday: Partly sunny, then gradually becoming sunny, with a high near 59. Northwest wind 8 to 10 mph.

    High: 59 °F

    Becoming
    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 41.

    Low: 41 °F

    Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 54.

    High: 54 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 44.

    Low: 44 °F

    Mostly Cloudy

  • Monday

    Monday: Mostly cloudy, with a high near 63.

    High: 63 °F

    Mostly Cloudy

Detailed Forecast

Today
Areas of frost before 9am. Otherwise, sunny, with a high near 49. Light southeast wind becoming south 6 to 11 mph in the morning.
Tonight
Patchy fog after 2am. Otherwise, mostly clear, with a low around 37. South wind 5 to 8 mph becoming calm after midnight.
Friday
Patchy fog before 8am. Otherwise, partly sunny, with a high near 56. Light southwest wind becoming south 6 to 11 mph in the morning.
Friday Night
Mostly cloudy, with a low around 42. South wind 8 to 10 mph.
Saturday
Partly sunny, then gradually becoming sunny, with a high near 59. Northwest wind 8 to 10 mph.
Saturday Night
Clear, with a low around 41.
Sunday
Mostly sunny, with a high near 54.
Sunday Night
Mostly cloudy, with a low around 44.
Monday
Mostly cloudy, with a high near 63.
Monday Night
Mostly cloudy, with a low around 53.
Tuesday
Partly sunny, with a high near 70.
Tuesday Night
Mostly cloudy, with a low around 54.
Wednesday
Partly sunny, with a high near 69.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Islip, Long Island Mac Arthur Airport NY
 40.8°N 73.09°W (Elev. 98 ft)
Last Update:
3:30 am EDT Apr 9, 2026
Forecast Valid:
4am EDT Apr 9, 2026-6pm EDT Apr 15, 2026
 
Forecast Discussion
 
Get as KML Get as XML

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation