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

-1°C

30°F

Humidity 96%
Wind Speed E 6 km/h
Barometer 1017.1 mb (30.03 in)
Dewpoint -2°C (29°F)
Visibility 4.83 km
Last update 18 Jan 4:56 am EST
Extended Forecast for

Islip NY

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

    NOW until 4:00am Mon

    Winter Weather Advisory

  • Overnight

    Low: -1 °C

    Chance
    Rain/Snow and
    Areas
    Freezing Fog

  • Sunday

    Sunday: Snow, possibly mixed with rain, becoming all snow after 4pm. Areas of freezing fog before 7am. High near 3. Light northeast wind increasing to 6 to 11 km/h in the morning. Chance of precipitation is 90%. New snow accumulation of less than one centimeter possible.

    High: 3 °C

    Rain/Snow and
    Areas
    Freezing Fog

  • Sunday Night

    Sunday Night: Snow, mainly before 10pm. Low around -6. North wind 8 to 11 km/h becoming west after midnight. Chance of precipitation is 80%. New snow accumulation of 3 to 7 centimeters possible.

    Low: -6 °C

    Snow then
    Chance Snow

  • M.L.King Day

    M.L.King Day: Mostly sunny, with a high near 1. Wind chill values between -5 and -10. West wind 11 to 16 km/h increasing to 21 to 26 km/h in the afternoon. Winds could gust as high as 47 km/h.

    High: 1 °C

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around -9. West wind 18 to 23 km/h, with gusts as high as 45 km/h.

    Low: -9 °C

    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near -4.

    High: -4 °C

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around -11.

    Low: -11 °C

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 3.

    High: 3 °C

    Mostly Sunny

Detailed Forecast

Overnight
A chance of rain and snow. Areas of freezing fog. Cloudy, with a low around -1. Calm wind. Chance of precipitation is 50%.
Sunday
Snow, possibly mixed with rain, becoming all snow after 4pm. Areas of freezing fog before 7am. High near 3. Light northeast wind increasing to 6 to 11 km/h in the morning. Chance of precipitation is 90%. New snow accumulation of less than one centimeter possible.
Sunday Night
Snow, mainly before 10pm. Low around -6. North wind 8 to 11 km/h becoming west after midnight. Chance of precipitation is 80%. New snow accumulation of 3 to 7 centimeters possible.
M.L.King Day
Mostly sunny, with a high near 1. Wind chill values between -5 and -10. West wind 11 to 16 km/h increasing to 21 to 26 km/h in the afternoon. Winds could gust as high as 47 km/h.
Monday Night
Partly cloudy, with a low around -9. West wind 18 to 23 km/h, with gusts as high as 45 km/h.
Tuesday
Sunny, with a high near -4.
Tuesday Night
Mostly clear, with a low around -11.
Wednesday
Mostly sunny, with a high near 3.
Wednesday Night
Mostly cloudy, with a low around -2.
Thursday
Partly sunny, with a high near 3.
Thursday Night
Partly cloudy, with a low around -7.
Friday
Mostly sunny, with a high near 2.
Friday Night
Mostly cloudy, with a low around -3.
Saturday
A chance of rain and snow. Mostly cloudy, with a high near 3. Chance of precipitation is 30%.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Islip NY
 40.73°N 73.22°W (Elev. 7 m)
Last Update:
4:59 am EST Jan 18, 2026
Forecast Valid:
5am EST Jan 18, 2026-6pm EST Jan 24, 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