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.

Partly Cloudy

50°F

10°C

Humidity 96%
Wind Speed Calm
Barometer 30.11 in (1019.4 mb)
Dewpoint 49°F (9°C)
Visibility 7.00 mi
Last update 4 Apr 5:56 am EDT
Extended Forecast for

Brentwood NY

  • Today

    Today: Patchy fog before 10am. Otherwise, partly sunny, with a high near 64. Light and variable wind becoming east 5 to 10 mph in the morning.

    High: 64 °F

    Patchy Fog
    then Partly
    Sunny

  • Tonight

    Tonight: A chance of rain between 11pm and 5am, then a chance of rain and thunderstorms after 5am. Cloudy, with a low around 42. East wind 7 to 10 mph, with gusts as high as 22 mph. Chance of precipitation is 40%.

    Low: 42 °F

    Chance Rain

  • Sunday

    Sunday: Rain and thunderstorms likely, then rain after 2pm. High near 59. South wind 10 to 15 mph, with gusts as high as 26 mph. Chance of precipitation is 100%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 59 °F

    Rain Likely
    then Rain

  • Sunday Night

    Sunday Night: Rain likely before 8pm. Cloudy during the early evening, then gradual clearing, with a low around 40. Northwest wind around 8 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

    Low: 40 °F

    Rain Likely
    then Partly
    Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 54. West wind around 10 mph.

    High: 54 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 39.

    Low: 39 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 51.

    High: 51 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 30.

    Low: 30 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 47.

    High: 47 °F

    Sunny

Detailed Forecast

Today
Patchy fog before 10am. Otherwise, partly sunny, with a high near 64. Light and variable wind becoming east 5 to 10 mph in the morning.
Tonight
A chance of rain between 11pm and 5am, then a chance of rain and thunderstorms after 5am. Cloudy, with a low around 42. East wind 7 to 10 mph, with gusts as high as 22 mph. Chance of precipitation is 40%.
Sunday
Rain and thunderstorms likely, then rain after 2pm. High near 59. South wind 10 to 15 mph, with gusts as high as 26 mph. Chance of precipitation is 100%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Sunday Night
Rain likely before 8pm. Cloudy during the early evening, then gradual clearing, with a low around 40. Northwest wind around 8 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Monday
Mostly sunny, with a high near 54. West wind around 10 mph.
Monday Night
Partly cloudy, with a low around 39.
Tuesday
Mostly sunny, with a high near 51.
Tuesday Night
Mostly clear, with a low around 30.
Wednesday
Sunny, with a high near 47.
Wednesday Night
Mostly clear, with a low around 35.
Thursday
Sunny, with a high near 54.
Thursday Night
Mostly clear, with a low around 42.
Friday
Mostly sunny, with a high near 59.
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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:
2:33 am EDT Apr 4, 2026
Forecast Valid:
6am EDT Apr 4, 2026-6pm EDT Apr 10, 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