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

18°F

-8°C

Humidity 52%
Wind Speed W 12 mph
Barometer 30.23 in (1023.9 mb)
Dewpoint 3°F (-16°C)
Visibility 10.00 mi
Wind Chill5°F (-15°C)
Last update 20 Jan 7:56 am EST
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

  • Today

    Today: Sunny, with a high near 23. Wind chill values between 5 and 10. West wind 11 to 15 mph, with gusts as high as 28 mph.

    High: 23 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 13. West wind 5 to 8 mph, with gusts as high as 21 mph.

    Low: 13 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 40. Wind chill values between 15 and 25. Light west wind becoming southwest 5 to 10 mph in the morning. Winds could gust as high as 22 mph.

    High: 40 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a steady temperature around 36. Southwest wind 8 to 10 mph, with gusts as high as 24 mph.

    Low: 36 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 43. Southwest wind 8 to 11 mph, with gusts as high as 22 mph.

    High: 43 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 24.

    Low: 24 °F

    Partly Cloudy

  • Friday

    Friday: Partly sunny, with a high near 33.

    High: 33 °F

    Partly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 10.

    Low: 10 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny and cold, with a high near 19.

    High: 19 °F

    Cold

Detailed Forecast

Today
Sunny, with a high near 23. Wind chill values between 5 and 10. West wind 11 to 15 mph, with gusts as high as 28 mph.
Tonight
Mostly clear, with a low around 13. West wind 5 to 8 mph, with gusts as high as 21 mph.
Wednesday
Mostly sunny, with a high near 40. Wind chill values between 15 and 25. Light west wind becoming southwest 5 to 10 mph in the morning. Winds could gust as high as 22 mph.
Wednesday Night
Mostly cloudy, with a steady temperature around 36. Southwest wind 8 to 10 mph, with gusts as high as 24 mph.
Thursday
Mostly sunny, with a high near 43. Southwest wind 8 to 11 mph, with gusts as high as 22 mph.
Thursday Night
Partly cloudy, with a low around 24.
Friday
Partly sunny, with a high near 33.
Friday Night
Partly cloudy, with a low around 10.
Saturday
Partly sunny and cold, with a high near 19.
Saturday Night
A 40 percent chance of snow. Mostly cloudy, with a low around 10.
Sunday
Snow likely. Mostly cloudy, with a high near 22. Chance of precipitation is 60%.
Sunday Night
A 40 percent chance of snow. Mostly cloudy, with a low around 12.
Monday
A 30 percent chance of snow. Mostly sunny, with a high near 24.
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ABOUT THIS FORECAST

 
Point Forecast:
Islip, Long Island Mac Arthur Airport NY
 40.78°N 73.09°W (Elev. 49 ft)
Last Update:
1:07 am EST Jan 20, 2026
Forecast Valid:
8am EST Jan 20, 2026-6pm EST Jan 26, 2026
 
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