National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Mostly Cloudy

69°F

21°C

Humidity 70%
Wind Speed S 9 mph
Barometer 29.82 in (1009.6 mb)
Dewpoint 59°F (15°C)
Visibility 10.00 mi
Last update 17 Jun 6:56 pm EDT
Extended Forecast for

Brentwood NY

  • Tonight

    Tonight: Increasing clouds, with a low around 63. South wind 7 to 9 mph.

    Low: 63 °F

    Increasing
    Clouds

  • Thursday

    Thursday: A slight chance of showers, then a chance of showers and thunderstorms after 2pm. Mostly cloudy, with a high near 82. South wind 14 to 18 mph, with gusts as high as 32 mph. Chance of precipitation is 40%.

    High: 82 °F

    Chance
    Showers

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 68. Southwest wind 8 to 13 mph, with gusts as high as 24 mph.

    Low: 68 °F

    Partly Cloudy

  • Juneteenth

    Juneteenth: Mostly cloudy, then gradually becoming sunny, with a high near 82. West wind 9 to 11 mph.

    High: 82 °F

    Decreasing
    Clouds

  • Friday Night

    Friday Night: Mostly clear, with a low around 65. West wind around 9 mph.

    Low: 65 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 81.

    High: 81 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 63.

    Low: 63 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 81.

    High: 81 °F

    Sunny

  • Sunday Night

    Sunday Night: A 40 percent chance of showers after 2am. Mostly cloudy, with a low around 65.

    Low: 65 °F

    Partly Cloudy
    then Chance
    Showers

Detailed Forecast

Tonight
Increasing clouds, with a low around 63. South wind 7 to 9 mph.
Thursday
A slight chance of showers, then a chance of showers and thunderstorms after 2pm. Mostly cloudy, with a high near 82. South wind 14 to 18 mph, with gusts as high as 32 mph. Chance of precipitation is 40%.
Thursday Night
Partly cloudy, with a low around 68. Southwest wind 8 to 13 mph, with gusts as high as 24 mph.
Juneteenth
Mostly cloudy, then gradually becoming sunny, with a high near 82. West wind 9 to 11 mph.
Friday Night
Mostly clear, with a low around 65. West wind around 9 mph.
Saturday
Sunny, with a high near 81.
Saturday Night
Mostly clear, with a low around 63.
Sunday
Sunny, with a high near 81.
Sunday Night
A 40 percent chance of showers after 2am. Mostly cloudy, with a low around 65.
Monday
Showers, mainly after 8am. High near 80. Chance of precipitation is 80%.
Monday Night
Showers. Low around 64. Chance of precipitation is 80%.
Tuesday
Mostly sunny, with a high near 81.
Tuesday Night
Mostly clear, with a low around 65.
Wednesday
Sunny, with a high near 81.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Brentwood NY
 40.75°N 73.24°W (Elev. 49 ft)
Last Update:
2:20 pm EDT Jun 17, 2026
Forecast Valid:
7pm EDT Jun 17, 2026-6pm EDT Jun 24, 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