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.

Overcast

43°F

6°C

Humidity 86%
Wind Speed SE 14 mph
Barometer 29.97 in (1015.0 mb)
Dewpoint 39°F (4°C)
Visibility 10.00 mi
Wind Chill36°F (2°C)
Last update 22 Mar 3:56 am EDT
Extended Forecast for

Brentwood NY

  • Today

    Today: A slight chance of rain before 2pm, then a chance of rain after 5pm. Mostly cloudy, with a high near 54. South wind 6 to 10 mph. Chance of precipitation is 30%.

    High: 54 °F

    Chance Rain

  • Tonight

    Tonight: Rain, mainly between 8pm and 11pm, then showers after 11pm. Low around 39. South wind around 5 mph becoming light and variable. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 39 °F

    Rain

  • Monday

    Monday: A 40 percent chance of rain before 2pm. Cloudy, then gradually becoming mostly sunny, with a high near 46. North wind 10 to 13 mph, with gusts as high as 23 mph.

    High: 46 °F

    Chance Rain

  • Monday Night

    Monday Night: Mostly clear, with a low around 30. Wind chill values between 25 and 30. Northwest wind 7 to 9 mph.

    Low: 30 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 45. Northwest wind around 7 mph becoming west in the afternoon.

    High: 45 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Increasing clouds, with a low around 34.

    Low: 34 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: Mostly cloudy, with a high near 49.

    High: 49 °F

    Mostly Cloudy

  • Wednesday Night

    Wednesday Night: A 30 percent chance of rain after 2am. Mostly cloudy, with a low around 38.

    Low: 38 °F

    Mostly Cloudy
    then Chance
    Rain

  • Thursday

    Thursday: A 30 percent chance of rain. Mostly cloudy, with a high near 52.

    High: 52 °F

    Chance Rain

Detailed Forecast

Today
A slight chance of rain before 2pm, then a chance of rain after 5pm. Mostly cloudy, with a high near 54. South wind 6 to 10 mph. Chance of precipitation is 30%.
Tonight
Rain, mainly between 8pm and 11pm, then showers after 11pm. Low around 39. South wind around 5 mph becoming light and variable. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Monday
A 40 percent chance of rain before 2pm. Cloudy, then gradually becoming mostly sunny, with a high near 46. North wind 10 to 13 mph, with gusts as high as 23 mph.
Monday Night
Mostly clear, with a low around 30. Wind chill values between 25 and 30. Northwest wind 7 to 9 mph.
Tuesday
Sunny, with a high near 45. Northwest wind around 7 mph becoming west in the afternoon.
Tuesday Night
Increasing clouds, with a low around 34.
Wednesday
Mostly cloudy, with a high near 49.
Wednesday Night
A 30 percent chance of rain after 2am. Mostly cloudy, with a low around 38.
Thursday
A 30 percent chance of rain. Mostly cloudy, with a high near 52.
Thursday Night
Rain likely, mainly after 2am. Mostly cloudy, with a low around 40. Chance of precipitation is 60%.
Friday
Rain likely. Partly sunny, with a high near 51. Chance of precipitation is 60%.
Friday Night
Partly cloudy, with a low around 26.
Saturday
Sunny, with a high near 42.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Brentwood NY
 40.78°N 73.24°W (Elev. 66 ft)
Last Update:
2:51 am EDT Mar 22, 2026
Forecast Valid:
4am EDT Mar 22, 2026-6pm EDT Mar 28, 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