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

25°F

-4°C

Humidity 32%
Wind Speed NE 8 mph
Barometer 30.67 in (1038.5 mb)
Dewpoint -1°F (-18°C)
Visibility 10.00 mi
Wind Chill16°F (-9°C)
Last update 2 Mar 9:56 am EST
Extended Forecast for

Brentwood NY

  • Today

    Today: Mostly sunny, with a high near 29. Wind chill values between 15 and 25. North wind around 6 mph becoming calm in the afternoon.

    High: 29 °F

    Mostly Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 22. Calm wind.

    Low: 22 °F

    Mostly Clear

  • Tuesday

    Tuesday: Rain likely, possibly mixed with snow before 1pm, then rain. High near 40. Southeast wind 3 to 6 mph. Chance of precipitation is 90%. New snow accumulation of less than a half inch possible.

    High: 40 °F

    Rain/Snow
    Likely then
    Rain/Snow

  • Tuesday Night

    Tuesday Night: Rain. Low around 35. South wind around 5 mph becoming light and variable. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 35 °F

    Rain

  • Wednesday

    Wednesday: A 20 percent chance of rain. Mostly cloudy, with a high near 45. West wind around 6 mph becoming light and variable in the afternoon.

    High: 45 °F

    Slight Chance
    Rain

  • Wednesday Night

    Wednesday Night: A 50 percent chance of rain. Cloudy, with a low around 37.

    Low: 37 °F

    Chance Rain

  • Thursday

    Thursday: A 40 percent chance of rain. Cloudy, with a high near 52.

    High: 52 °F

    Chance Rain

  • Thursday Night

    Thursday Night: A 50 percent chance of rain. Cloudy, with a low around 37.

    Low: 37 °F

    Chance Rain

  • Friday

    Friday: A 40 percent chance of rain before 1pm. Cloudy, with a high near 44.

    High: 44 °F

    Chance Rain

Detailed Forecast

Today
Mostly sunny, with a high near 29. Wind chill values between 15 and 25. North wind around 6 mph becoming calm in the afternoon.
Tonight
Mostly clear, with a low around 22. Calm wind.
Tuesday
Rain likely, possibly mixed with snow before 1pm, then rain. High near 40. Southeast wind 3 to 6 mph. Chance of precipitation is 90%. New snow accumulation of less than a half inch possible.
Tuesday Night
Rain. Low around 35. South wind around 5 mph becoming light and variable. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Wednesday
A 20 percent chance of rain. Mostly cloudy, with a high near 45. West wind around 6 mph becoming light and variable in the afternoon.
Wednesday Night
A 50 percent chance of rain. Cloudy, with a low around 37.
Thursday
A 40 percent chance of rain. Cloudy, with a high near 52.
Thursday Night
A 50 percent chance of rain. Cloudy, with a low around 37.
Friday
A 40 percent chance of rain before 1pm. Cloudy, with a high near 44.
Friday Night
Mostly cloudy, with a low around 36.
Saturday
Cloudy, with a high near 51.
Saturday Night
A 40 percent chance of rain. Mostly cloudy, with a low around 41.
Sunday
Mostly cloudy, with a high near 52.
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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:
2:30 am EST Mar 2, 2026
Forecast Valid:
10am EST Mar 2, 2026-6pm EDT Mar 8, 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