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

64°F

18°C

Humidity 78%
Wind Speed SE 5 mph
Barometer 30.17 in (1021.4 mb)
Dewpoint 57°F (14°C)
Visibility 10.00 mi
Last update 15 Jun 2:56 pm EDT
Extended Forecast for

Brentwood NY

  • This Afternoon

    This Afternoon: A 20 percent chance of light rain. Mostly cloudy, with a high near 67. East wind around 8 mph.

    High: 67 °F

    Slight Chance
    Light Rain

  • Tonight

    Tonight: A 20 percent chance of light rain. Mostly cloudy, with a low around 60. East wind around 6 mph.

    Low: 60 °F

    Slight Chance
    Light Rain

  • Monday

    Monday: A 20 percent chance of light rain after 2pm. Mostly cloudy, with a high near 69. East wind 8 to 10 mph.

    High: 69 °F

    Cloudy then
    Slight Chance
    Light Rain

  • Monday Night

    Monday Night: A slight chance of light rain before 8pm, then a slight chance of light rain after 2am. Mostly cloudy, with a low around 61. East wind 5 to 7 mph. Chance of precipitation is 20%.

    Low: 61 °F

    Mostly Cloudy
    then Slight
    Chance Light
    Rain

  • Tuesday

    Tuesday: Cloudy, with a high near 72. East wind 6 to 8 mph.

    High: 72 °F

    Cloudy

  • Tuesday Night

    Tuesday Night: A 50 percent chance of showers. Cloudy, with a low around 63.

    Low: 63 °F

    Chance
    Showers

  • Wednesday

    Wednesday: A 30 percent chance of showers before 2pm. Cloudy, then gradually becoming mostly sunny, with a high near 82.

    High: 82 °F

    Chance
    Showers

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 67.

    Low: 67 °F

    Partly Cloudy

  • Juneteenth

    Juneteenth: A 30 percent chance of showers and thunderstorms after 2pm. Sunny, with a high near 87.

    High: 87 °F

    Sunny then
    Chance
    T-storms

Detailed Forecast

This Afternoon
A 20 percent chance of light rain. Mostly cloudy, with a high near 67. East wind around 8 mph.
Tonight
A 20 percent chance of light rain. Mostly cloudy, with a low around 60. East wind around 6 mph.
Monday
A 20 percent chance of light rain after 2pm. Mostly cloudy, with a high near 69. East wind 8 to 10 mph.
Monday Night
A slight chance of light rain before 8pm, then a slight chance of light rain after 2am. Mostly cloudy, with a low around 61. East wind 5 to 7 mph. Chance of precipitation is 20%.
Tuesday
Cloudy, with a high near 72. East wind 6 to 8 mph.
Tuesday Night
A 50 percent chance of showers. Cloudy, with a low around 63.
Wednesday
A 30 percent chance of showers before 2pm. Cloudy, then gradually becoming mostly sunny, with a high near 82.
Wednesday Night
Partly cloudy, with a low around 67.
Juneteenth
A 30 percent chance of showers and thunderstorms after 2pm. Sunny, with a high near 87.
Thursday Night
A chance of showers and thunderstorms before 8pm, then a chance of showers between 8pm and 2am. Partly cloudy, with a low around 67. Chance of precipitation is 30%.
Friday
Sunny, with a high near 83.
Friday Night
Partly cloudy, with a low around 63.
Saturday
Sunny, with a high near 81.
Saturday Night
Partly cloudy, with a low around 66.
Sunday
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 73.24°W (Elev. 66 ft)
Last Update:
3:21 pm EDT Jun 15, 2025
Forecast Valid:
3pm EDT Jun 15, 2025-6pm EDT Jun 22, 2025
 
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