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

62°F

17°C

Humidity 90%
Wind Speed N 3 mph
Barometer 30.15 in (1020.9 mb)
Dewpoint 59°F (15°C)
Visibility 10.00 mi
Last update 25 Jul 2:56 am EDT
Extended Forecast for

Brentwood NY

  • Overnight

    Overnight: Partly cloudy, with a low around 61. Calm wind.

    Low: 61 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 81. East wind 5 to 10 mph.

    High: 81 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 62. East wind around 6 mph becoming calm in the evening.

    Low: 62 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 83. Northeast wind 5 to 7 mph.

    High: 83 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 65. South wind around 5 mph becoming calm in the evening.

    Low: 65 °F

    Mostly Clear

  • Monday

    Monday: Mostly sunny, with a high near 83.

    High: 83 °F

    Mostly Sunny

  • Monday Night

    Monday Night: A 40 percent chance of showers after 2am. Mostly cloudy, with a low around 68.

    Low: 68 °F

    Mostly Cloudy
    then Chance
    Showers

  • Tuesday

    Tuesday: Showers likely, then showers and possibly a thunderstorm after 2pm. High near 82. Chance of precipitation is 80%.

    High: 82 °F

    Showers

  • Tuesday Night

    Tuesday Night: Showers and possibly a thunderstorm before 2am, then a chance of showers. Low around 67. Chance of precipitation is 80%.

    Low: 67 °F

    Showers

Detailed Forecast

Overnight
Partly cloudy, with a low around 61. Calm wind.
Saturday
Sunny, with a high near 81. East wind 5 to 10 mph.
Saturday Night
Clear, with a low around 62. East wind around 6 mph becoming calm in the evening.
Sunday
Sunny, with a high near 83. Northeast wind 5 to 7 mph.
Sunday Night
Mostly clear, with a low around 65. South wind around 5 mph becoming calm in the evening.
Monday
Mostly sunny, with a high near 83.
Monday Night
A 40 percent chance of showers after 2am. Mostly cloudy, with a low around 68.
Tuesday
Showers likely, then showers and possibly a thunderstorm after 2pm. High near 82. Chance of precipitation is 80%.
Tuesday Night
Showers and possibly a thunderstorm before 2am, then a chance of showers. Low around 67. Chance of precipitation is 80%.
Wednesday
A 40 percent chance of showers. Partly sunny, with a high near 81.
Wednesday Night
A 30 percent chance of showers. Partly cloudy, with a low around 66.
Thursday
Mostly sunny, with a high near 82.
Thursday Night
Partly cloudy, with a low around 67.
Friday
Mostly sunny, with a high near 84.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Brentwood NY
 40.78°N 73.27°W (Elev. 98 ft)
Last Update:
2:44 am EDT Jul 25, 2026
Forecast Valid:
3am EDT Jul 25, 2026-6pm EDT Jul 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