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

38°F

3°C

Humidity 60%
Wind Speed SW 10 mph
Barometer 30.36 in (1028.2 mb)
Dewpoint 25°F (-4°C)
Visibility 10.00 mi
Wind Chill31°F (-1°C)
Last update 24 Mar 10:56 pm EDT
Extended Forecast for

Brentwood NY

  • Tonight

    Tonight: Mostly cloudy, with a low around 31. Southwest wind around 7 mph.

    Low: 31 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 51. Light west wind becoming south 5 to 9 mph in the morning.

    High: 51 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: Cloudy, with a low around 40. South wind around 6 mph.

    Low: 40 °F

    Cloudy

  • Thursday

    Thursday: Mostly cloudy, with a high near 60. Southwest wind 7 to 14 mph.

    High: 60 °F

    Mostly Cloudy

  • Thursday Night

    Thursday Night: Rain, mainly after 2am. Low around 47. Southwest wind around 10 mph. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch possible.

    Low: 47 °F

    Slight Chance
    Rain then
    Rain

  • Friday

    Friday: Rain likely, mainly before 8am. Mostly cloudy, with a high near 56. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 56 °F

    Rain Likely
    then Mostly
    Cloudy

  • Friday Night

    Friday Night: Partly cloudy, with a low around 28.

    Low: 28 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 43.

    High: 43 °F

    Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 31.

    Low: 31 °F

    Partly Cloudy

Detailed Forecast

Tonight
Mostly cloudy, with a low around 31. Southwest wind around 7 mph.
Wednesday
Partly sunny, with a high near 51. Light west wind becoming south 5 to 9 mph in the morning.
Wednesday Night
Cloudy, with a low around 40. South wind around 6 mph.
Thursday
Mostly cloudy, with a high near 60. Southwest wind 7 to 14 mph.
Thursday Night
Rain, mainly after 2am. Low around 47. Southwest wind around 10 mph. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch possible.
Friday
Rain likely, mainly before 8am. Mostly cloudy, with a high near 56. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.
Friday Night
Partly cloudy, with a low around 28.
Saturday
Sunny, with a high near 43.
Saturday Night
Partly cloudy, with a low around 31.
Sunday
Sunny, with a high near 47.
Sunday Night
Partly cloudy, with a low around 36.
Monday
Partly sunny, with a high near 52.
Monday Night
Partly cloudy, with a low around 38.
Tuesday
Partly sunny, with a high near 54.
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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:
7:09 pm EDT Mar 24, 2026
Forecast Valid:
11pm EDT Mar 24, 2026-6pm EDT Mar 31, 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