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.

Partly Cloudy

31°F

-1°C

Humidity 96%
Wind Speed Calm
Barometer 30.11 in (1019.5 mb)
Dewpoint 30°F (-1°C)
Visibility 10.00 mi
Last update 17 Jan 7:56 pm EST
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

Winter Weather Advisory January 18, 10:00am until January 18, 10:00pm
Click here for hazard details and duration
Winter Weather Advisory

  • Tonight

    Tonight: A slight chance of rain between 1am and 4am, then a chance of snow. Increasing clouds, with a low around 30. West wind around 5 mph becoming calm in the evening. Chance of precipitation is 40%.

    Low: 30 °F

    Mostly Cloudy
    then Chance
    Rain/Snow

  • Sunday

    Sunday: Periods of rain and snow, becoming all snow after 11am. High near 35. Calm wind becoming northeast 5 to 7 mph in the afternoon. Chance of precipitation is 80%. New snow accumulation of 1 to 2 inches possible.

    High: 35 °F

    Rain/Snow
    then Snow

  • Sunday Night

    Sunday Night: A 40 percent chance of snow before 1am. Cloudy, then gradually becoming partly cloudy, with a low around 23. Northwest wind 3 to 6 mph.

    Low: 23 °F

    Chance Snow

  • M.L.King Day

    M.L.King Day: Mostly sunny, with a high near 33. Wind chill values between 15 and 25. West wind 6 to 14 mph, with gusts as high as 24 mph.

    High: 33 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 17. West wind around 10 mph, with gusts as high as 24 mph.

    Low: 17 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 24.

    High: 24 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 14.

    Low: 14 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 38.

    High: 38 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 28.

    Low: 28 °F

    Mostly Cloudy

Detailed Forecast

Tonight
A slight chance of rain between 1am and 4am, then a chance of snow. Increasing clouds, with a low around 30. West wind around 5 mph becoming calm in the evening. Chance of precipitation is 40%.
Sunday
Periods of rain and snow, becoming all snow after 11am. High near 35. Calm wind becoming northeast 5 to 7 mph in the afternoon. Chance of precipitation is 80%. New snow accumulation of 1 to 2 inches possible.
Sunday Night
A 40 percent chance of snow before 1am. Cloudy, then gradually becoming partly cloudy, with a low around 23. Northwest wind 3 to 6 mph.
M.L.King Day
Mostly sunny, with a high near 33. Wind chill values between 15 and 25. West wind 6 to 14 mph, with gusts as high as 24 mph.
Monday Night
Partly cloudy, with a low around 17. West wind around 10 mph, with gusts as high as 24 mph.
Tuesday
Mostly sunny, with a high near 24.
Tuesday Night
Mostly clear, with a low around 14.
Wednesday
Mostly sunny, with a high near 38.
Wednesday Night
Mostly cloudy, with a low around 28.
Thursday
Partly sunny, with a high near 38.
Thursday Night
Partly cloudy, with a low around 20.
Friday
Mostly sunny, with a high near 33.
Friday Night
Partly cloudy, with a low around 22.
Saturday
Partly sunny, with a high near 33.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Islip, Long Island Mac Arthur Airport NY
 40.8°N 73.09°W (Elev. 98 ft)
Last Update:
5:41 pm EST Jan 17, 2026
Forecast Valid:
8pm EST Jan 17, 2026-6pm EST Jan 24, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation