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

29°F

-2°C

Humidity 96%
Wind Speed Calm
Barometer 30.08 in (1018.6 mb)
Dewpoint 28°F (-2°C)
Visibility 2.50 mi
Last update 18 Jan 2:56 am EST
Extended Forecast for

Islip, Long Island Mac Arthur Airport NY

Winter Weather Advisory January 18, 10:00am until January 19, 04:00am
Click here for hazard details and duration
Winter Weather Advisory

  • Overnight

    Overnight: A 40 percent chance of snow after 4am. Areas of freezing fog. Cloudy, with a low around 30. Calm wind.

    Low: 30 °F

    Chance Snow
    and Areas
    Freezing Fog

  • Sunday

    Sunday: A chance of snow before 7am, then snow, possibly mixed with rain between 7am and 4pm, then snow after 4pm. Areas of freezing fog before 7am. High near 37. Calm wind becoming northeast around 6 mph in the afternoon. Chance of precipitation is 100%. New snow accumulation of less than one inch possible.

    High: 37 °F

    Rain/Snow and
    Areas
    Freezing Fog

  • Sunday Night

    Sunday Night: Snow, mainly before 10pm. Low around 21. Light and variable wind becoming northwest around 6 mph in the evening. Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible.

    Low: 21 °F

    Snow then
    Chance Snow

  • M.L.King Day

    M.L.King Day: Mostly sunny, with a high near 32. Wind chill values between 15 and 20. West wind 6 to 15 mph, with gusts as high as 28 mph.

    High: 32 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 15. West wind 10 to 13 mph, with gusts as high as 26 mph.

    Low: 15 °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 12.

    Low: 12 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 37.

    High: 37 °F

    Mostly Sunny

  • Wednesday Night

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

    Low: 28 °F

    Mostly Cloudy

Detailed Forecast

Overnight
A 40 percent chance of snow after 4am. Areas of freezing fog. Cloudy, with a low around 30. Calm wind.
Sunday
A chance of snow before 7am, then snow, possibly mixed with rain between 7am and 4pm, then snow after 4pm. Areas of freezing fog before 7am. High near 37. Calm wind becoming northeast around 6 mph in the afternoon. Chance of precipitation is 100%. New snow accumulation of less than one inch possible.
Sunday Night
Snow, mainly before 10pm. Low around 21. Light and variable wind becoming northwest around 6 mph in the evening. Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible.
M.L.King Day
Mostly sunny, with a high near 32. Wind chill values between 15 and 20. West wind 6 to 15 mph, with gusts as high as 28 mph.
Monday Night
Partly cloudy, with a low around 15. West wind 10 to 13 mph, with gusts as high as 26 mph.
Tuesday
Mostly sunny, with a high near 24.
Tuesday Night
Mostly clear, with a low around 12.
Wednesday
Mostly sunny, with a high near 37.
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 35.
Friday Night
Mostly cloudy, with a low around 25.
Saturday
A chance of rain and snow. Mostly cloudy, with a high near 37. Chance of precipitation is 30%.
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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:
1:04 am EST Jan 18, 2026
Forecast Valid:
3am EST Jan 18, 2026-6pm EST Jan 24, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

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High Temperature

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Chance of Precipitation