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.

Mostly Cloudy

39°F

4°C

Humidity 53%
Wind Speed N 9 mph
Barometer 29.88 in (1011.9 mb)
Dewpoint 23°F (-5°C)
Visibility 10.00 mi
Wind Chill33°F (1°C)
Last update 26 Feb 11:56 am EST
Extended Forecast for

Brentwood NY

  • This Afternoon

    This Afternoon: A slight chance of rain and snow after 1pm. Mostly cloudy, with a high near 37. Northwest wind around 5 mph becoming calm. Chance of precipitation is 20%.

    High: 37 °F

    Slight Chance
    Rain/Snow

  • Tonight

    Tonight: Mostly cloudy, then gradually becoming mostly clear, with a low around 22. Calm wind.

    Low: 22 °F

    Decreasing
    Clouds

  • Friday

    Friday: Sunny, with a high near 38. Wind chill values between 25 and 35. Calm wind becoming south around 5 mph.

    High: 38 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 29. Light south wind.

    Low: 29 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 45. Southwest wind 3 to 6 mph.

    High: 45 °F

    Sunny

  • Saturday Night

    Saturday Night: Increasing clouds, with a low around 29.

    Low: 29 °F

    Increasing
    Clouds

  • Sunday

    Sunday: Cloudy, then gradual clearing during the afternoon, with a high near 38.

    High: 38 °F

    Clearing Late

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 17.

    Low: 17 °F

    Partly Cloudy

  • Monday

    Monday: A 30 percent chance of snow. Mostly cloudy, with a high near 28.

    High: 28 °F

    Chance Snow

Detailed Forecast

This Afternoon
A slight chance of rain and snow after 1pm. Mostly cloudy, with a high near 37. Northwest wind around 5 mph becoming calm. Chance of precipitation is 20%.
Tonight
Mostly cloudy, then gradually becoming mostly clear, with a low around 22. Calm wind.
Friday
Sunny, with a high near 38. Wind chill values between 25 and 35. Calm wind becoming south around 5 mph.
Friday Night
Mostly clear, with a low around 29. Light south wind.
Saturday
Sunny, with a high near 45. Southwest wind 3 to 6 mph.
Saturday Night
Increasing clouds, with a low around 29.
Sunday
Cloudy, then gradual clearing during the afternoon, with a high near 38.
Sunday Night
Partly cloudy, with a low around 17.
Monday
A 30 percent chance of snow. Mostly cloudy, with a high near 28.
Monday Night
A 30 percent chance of snow after 1am. Mostly cloudy, with a low around 19.
Tuesday
A chance of rain and snow. Mostly cloudy, with a high near 36. Chance of precipitation is 30%.
Tuesday Night
A chance of rain and snow. Cloudy, with a low around 28. Chance of precipitation is 50%.
Wednesday
A 50 percent chance of rain. Partly sunny, with a high near 42.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Brentwood NY
 40.78°N 73.24°W (Elev. 66 ft)
Last Update:
10:42 am EST Feb 26, 2026
Forecast Valid:
12pm EST Feb 26, 2026-6pm EST Mar 4, 2026
 
Forecast Discussion
 
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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