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

19°F

-7°C

Humidity 62%
Wind Speed Calm
Barometer 30.14 in (1020.9 mb)
Dewpoint 8°F (-13°C)
Visibility 10.00 mi
Last update 10 Feb 2:56 am EST
Extended Forecast for

Brentwood NY

  • Overnight

    Overnight: Mostly cloudy, with a low around 17. Calm wind.

    Low: 17 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 37. Wind chill values between 20 and 30. Calm wind becoming south around 6 mph in the afternoon.

    High: 37 °F

    Mostly Cloudy

  • Tuesday Night

    Tuesday Night: Rain and sleet likely before 1am, then a chance of rain between 1am and 4am. Mostly cloudy, with a low around 29. Light and variable wind becoming west around 5 mph after midnight. Chance of precipitation is 70%. Little or no sleet accumulation expected.

    Low: 29 °F

    Rain/Sleet
    Likely

  • Wednesday

    Wednesday: Mostly sunny, with a high near 38. West wind 6 to 13 mph, with gusts as high as 26 mph.

    High: 38 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 23. West wind around 9 mph, with gusts as high as 24 mph.

    Low: 23 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 34.

    High: 34 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 19.

    Low: 19 °F

    Mostly Cloudy

  • Friday

    Friday: Sunny, with a high near 34.

    High: 34 °F

    Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 24.

    Low: 24 °F

    Mostly Cloudy

Detailed Forecast

Overnight
Mostly cloudy, with a low around 17. Calm wind.
Tuesday
Mostly cloudy, with a high near 37. Wind chill values between 20 and 30. Calm wind becoming south around 6 mph in the afternoon.
Tuesday Night
Rain and sleet likely before 1am, then a chance of rain between 1am and 4am. Mostly cloudy, with a low around 29. Light and variable wind becoming west around 5 mph after midnight. Chance of precipitation is 70%. Little or no sleet accumulation expected.
Wednesday
Mostly sunny, with a high near 38. West wind 6 to 13 mph, with gusts as high as 26 mph.
Wednesday Night
Partly cloudy, with a low around 23. West wind around 9 mph, with gusts as high as 24 mph.
Thursday
Mostly sunny, with a high near 34.
Thursday Night
Mostly cloudy, with a low around 19.
Friday
Sunny, with a high near 34.
Friday Night
Mostly cloudy, with a low around 24.
Saturday
Mostly sunny, with a high near 37.
Saturday Night
Partly cloudy, with a low around 23.
Sunday
Mostly cloudy, with a high near 38.
Sunday Night
Rain likely. Cloudy, with a low around 30. Chance of precipitation is 60%.
Washington's Birthday
A 50 percent chance of rain. Cloudy, with a high near 40.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Brentwood NY
 40.78°N 73.24°W (Elev. 66 ft)
Last Update:
2:28 am EST Feb 10, 2026
Forecast Valid:
3am EST Feb 10, 2026-6pm EST Feb 16, 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