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

41°F

5°C

Humidity 79%
Wind Speed Calm
Barometer 30.10 in (1019.4 mb)
Dewpoint 35°F (2°C)
Visibility 10.00 mi
Last update 6 Apr 9:56 pm EDT
Extended Forecast for

Brentwood NY

  • Tonight

    Tonight: A chance of sprinkles before midnight, then a chance of showers, mainly after 2am. Mostly cloudy, with a low around 40. Southeast wind around 5 mph becoming calm after midnight. Chance of precipitation is 30%.

    Low: 40 °F

    Mostly Cloudy
    then Chance
    Showers

  • Tuesday

    Tuesday: A slight chance of showers before 8am, then a slight chance of showers after 2pm. Mostly sunny, with a high near 52. Northwest wind 6 to 14 mph, with gusts as high as 25 mph. Chance of precipitation is 20%.

    High: 52 °F

    Mostly Sunny
    then Slight
    Chance
    Showers

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 30. Wind chill values between 20 and 25. North wind around 10 mph, with gusts as high as 22 mph.

    Low: 30 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 47. Wind chill values between 20 and 30 early. North wind around 7 mph becoming southeast in the afternoon.

    High: 47 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 33. Light southeast wind.

    Low: 33 °F

    Mostly Clear

  • Thursday

    Thursday: Mostly sunny, with a high near 51.

    High: 51 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 41.

    Low: 41 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 61.

    High: 61 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 47.

    Low: 47 °F

    Partly Cloudy

Detailed Forecast

Tonight
A chance of sprinkles before midnight, then a chance of showers, mainly after 2am. Mostly cloudy, with a low around 40. Southeast wind around 5 mph becoming calm after midnight. Chance of precipitation is 30%.
Tuesday
A slight chance of showers before 8am, then a slight chance of showers after 2pm. Mostly sunny, with a high near 52. Northwest wind 6 to 14 mph, with gusts as high as 25 mph. Chance of precipitation is 20%.
Tuesday Night
Mostly clear, with a low around 30. Wind chill values between 20 and 25. North wind around 10 mph, with gusts as high as 22 mph.
Wednesday
Sunny, with a high near 47. Wind chill values between 20 and 30 early. North wind around 7 mph becoming southeast in the afternoon.
Wednesday Night
Mostly clear, with a low around 33. Light southeast wind.
Thursday
Mostly sunny, with a high near 51.
Thursday Night
Partly cloudy, with a low around 41.
Friday
Mostly sunny, with a high near 61.
Friday Night
Partly cloudy, with a low around 47.
Saturday
Mostly sunny, with a high near 65.
Saturday Night
Partly cloudy, with a low around 45.
Sunday
Mostly sunny, with a high near 59.
Sunday Night
Mostly cloudy, with a low around 46.
Monday
Partly sunny, with a high near 65.
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:
8:00 pm EDT Apr 6, 2026
Forecast Valid:
10pm EDT Apr 6, 2026-6pm EDT Apr 13, 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