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

25°F

-4°C

Humidity 37%
Wind Speed W 20 G 36 mph
Barometer 30.09 in (1018.9 mb)
Dewpoint 2°F (-17°C)
Visibility 10.00 mi
Wind Chill11°F (-12°C)
Last update 20 Jan 12:56 am EST
Extended Forecast for

Islip NY

  • Overnight

    Overnight: Mostly clear, with a low around 16. Wind chill values between 5 and 10. West wind around 11 mph, with gusts as high as 25 mph.

    Low: 16 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 24. Wind chill values between 5 and 10. West wind 11 to 15 mph, with gusts as high as 28 mph.

    High: 24 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 14. Wind chill values between 5 and 10. West wind 6 to 10 mph, with gusts as high as 22 mph.

    Low: 14 °F

    Mostly Clear

  • Wednesday

    Wednesday: Increasing clouds, with a high near 40. Wind chill values between 10 and 20. West wind 5 to 13 mph becoming south in the afternoon.

    High: 40 °F

    Increasing
    Clouds

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a steady temperature around 36. Southwest wind 10 to 13 mph, with gusts as high as 25 mph.

    Low: 36 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 43.

    High: 43 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 25.

    Low: 25 °F

    Partly Cloudy

  • Friday

    Friday: Partly sunny, with a high near 34.

    High: 34 °F

    Partly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 11.

    Low: 11 °F

    Partly Cloudy

Detailed Forecast

Overnight
Mostly clear, with a low around 16. Wind chill values between 5 and 10. West wind around 11 mph, with gusts as high as 25 mph.
Tuesday
Sunny, with a high near 24. Wind chill values between 5 and 10. West wind 11 to 15 mph, with gusts as high as 28 mph.
Tuesday Night
Mostly clear, with a low around 14. Wind chill values between 5 and 10. West wind 6 to 10 mph, with gusts as high as 22 mph.
Wednesday
Increasing clouds, with a high near 40. Wind chill values between 10 and 20. West wind 5 to 13 mph becoming south in the afternoon.
Wednesday Night
Mostly cloudy, with a steady temperature around 36. Southwest wind 10 to 13 mph, with gusts as high as 25 mph.
Thursday
Mostly sunny, with a high near 43.
Thursday Night
Partly cloudy, with a low around 25.
Friday
Partly sunny, with a high near 34.
Friday Night
Partly cloudy, with a low around 11.
Saturday
Partly sunny and cold, with a high near 20.
Saturday Night
A 40 percent chance of snow. Mostly cloudy, with a low around 11.
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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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Islip NY
 40.73°N 73.22°W (Elev. 7 ft)
Last Update:
1:07 am EST Jan 20, 2026
Forecast Valid:
1am EST Jan 20, 2026-6pm EST Jan 26, 2026
 
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Additional Resources

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Chance of Precipitation