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.

Fog/Mist

26°F

-3°C

Humidity 96%
Wind Speed Calm
Barometer 30.12 in (1019.9 mb)
Dewpoint 25°F (-4°C)
Visibility 1.50 mi
Last update 28 Feb 3:56 am EST
Extended Forecast for

Brentwood NY

  • Today

    Today: Patchy fog before 9am. Otherwise, mostly sunny, with a high near 45. South wind 3 to 8 mph.

    High: 45 °F

    Patchy Fog
    then Mostly
    Sunny

  • Tonight

    Tonight: Patchy fog between 10pm and 1am. Otherwise, partly cloudy, with a low around 28. Light and variable wind becoming north 5 to 8 mph after midnight.

    Low: 28 °F

    Patchy Fog

  • Sunday

    Sunday: Snow likely, mainly between 10am and 4pm. Increasing clouds, with a high near 37. Wind chill values between 25 and 30. North wind 7 to 9 mph. Chance of precipitation is 60%. New snow accumulation of less than one inch possible.

    High: 37 °F

    Snow Likely

  • Sunday Night

    Sunday Night: A 30 percent chance of snow before 7pm. Mostly clear, with a low around 15. Wind chill values between 10 and 15. North wind 7 to 13 mph.

    Low: 15 °F

    Chance Snow
    then Mostly
    Clear

  • Monday

    Monday: Sunny, with a high near 28. North wind 5 to 8 mph.

    High: 28 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 19.

    Low: 19 °F

    Mostly Clear

  • Tuesday

    Tuesday: A 50 percent chance of rain after 1pm. Increasing clouds, with a high near 40.

    High: 40 °F

    Mostly Cloudy
    then Chance
    Rain

  • Tuesday Night

    Tuesday Night: Rain. Low around 35. Chance of precipitation is 90%.

    Low: 35 °F

    Rain

  • Wednesday

    Wednesday: A 30 percent chance of rain before 1pm. Mostly cloudy, with a high near 46.

    High: 46 °F

    Chance Rain

Detailed Forecast

Today
Patchy fog before 9am. Otherwise, mostly sunny, with a high near 45. South wind 3 to 8 mph.
Tonight
Patchy fog between 10pm and 1am. Otherwise, partly cloudy, with a low around 28. Light and variable wind becoming north 5 to 8 mph after midnight.
Sunday
Snow likely, mainly between 10am and 4pm. Increasing clouds, with a high near 37. Wind chill values between 25 and 30. North wind 7 to 9 mph. Chance of precipitation is 60%. New snow accumulation of less than one inch possible.
Sunday Night
A 30 percent chance of snow before 7pm. Mostly clear, with a low around 15. Wind chill values between 10 and 15. North wind 7 to 13 mph.
Monday
Sunny, with a high near 28. North wind 5 to 8 mph.
Monday Night
Mostly clear, with a low around 19.
Tuesday
A 50 percent chance of rain after 1pm. Increasing clouds, with a high near 40.
Tuesday Night
Rain. Low around 35. Chance of precipitation is 90%.
Wednesday
A 30 percent chance of rain before 1pm. Mostly cloudy, with a high near 46.
Wednesday Night
A 30 percent chance of rain after 1am. Mostly cloudy, with a low around 33.
Thursday
A 40 percent chance of rain. Cloudy, with a high near 47.
Thursday Night
A 50 percent chance of rain. Cloudy, with a low around 38.
Friday
A 30 percent chance of rain. Cloudy, with a high near 49.
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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:
12:55 am EST Feb 28, 2026
Forecast Valid:
4am EST Feb 28, 2026-6pm EST Mar 6, 2026
 
Forecast Discussion
 
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Additional Resources

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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