Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

A Few Clouds

30°F

-1°C

Humidity 43%
Wind Speed N 8 mph
Barometer 29.96 in (1014.6 mb)
Dewpoint 10°F (-12°C)
Visibility 10.00 mi
Wind Chill22°F (-6°C)
Last update 5 Feb 2:56 pm EST
Extended Forecast for

Port Jefferson NY

Extreme Cold Watch February 7, 06:00pm until February 8, 01:00pm
Click here for hazard details and duration
Extreme Cold Watch
  • Tonight

    Tonight: Increasing clouds, with a low around 21. Wind chill values between 10 and 15. Northeast wind 5 to 9 mph.

    Low: 21 °F

    Increasing
    Clouds

  • Friday

    Friday: Mostly cloudy, with a high near 28. Wind chill values between 10 and 20. Northeast wind 5 to 9 mph becoming calm  in the afternoon.

    High: 28 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: Snow, mainly after 1am.  Steady temperature around 27. Wind chill values between 20 and 25. Calm wind becoming west around 6 mph after midnight.  Chance of precipitation is 80%. New snow accumulation of less than one inch possible.

    Low: 27 °F

    Chance Snow
    then Snow

  • Saturday

    Saturday: Snow, mainly before 1pm.  Temperature falling to around 16 by 5pm. Wind chill values between -5 and 5. Windy, with a northwest wind 11 to 21 mph increasing to 29 to 39 mph. Winds could gust as high as 55 mph.  Chance of precipitation is 80%. New snow accumulation of around an inch possible.

    High: 27 °F

    Snow and
    Windy

  • Saturday Night

    Saturday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 8. Very windy, with a northwest wind 38 to 43 mph decreasing to 32 to 37 mph after midnight.

    Low: 8 °F

    Decreasing
    Clouds and
    Very Windy

  • Sunday

    Sunday: Sunny and cold, with a high near 17. Windy.

    High: 17 °F

    Cold and
    Windy

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 11. Blustery.

    Low: 11 °F

    Mostly Clear
    and Blustery

  • Monday

    Monday: Mostly sunny, with a high near 24.

    High: 24 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 16.

    Low: 16 °F

    Partly Cloudy

Detailed Forecast

Tonight
Increasing clouds, with a low around 21. Wind chill values between 10 and 15. Northeast wind 5 to 9 mph.
Friday
Mostly cloudy, with a high near 28. Wind chill values between 10 and 20. Northeast wind 5 to 9 mph becoming calm in the afternoon.
Friday Night
Snow, mainly after 1am. Steady temperature around 27. Wind chill values between 20 and 25. Calm wind becoming west around 6 mph after midnight. Chance of precipitation is 80%. New snow accumulation of less than one inch possible.
Saturday
Snow, mainly before 1pm. Temperature falling to around 16 by 5pm. Wind chill values between -5 and 5. Windy, with a northwest wind 11 to 21 mph increasing to 29 to 39 mph. Winds could gust as high as 55 mph. Chance of precipitation is 80%. New snow accumulation of around an inch possible.
Saturday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 8. Very windy, with a northwest wind 38 to 43 mph decreasing to 32 to 37 mph after midnight.
Sunday
Sunny and cold, with a high near 17. Windy.
Sunday Night
Mostly clear, with a low around 11. Blustery.
Monday
Mostly sunny, with a high near 24.
Monday Night
Partly cloudy, with a low around 16.
Tuesday
Mostly sunny, with a high near 28.
Tuesday Night
Mostly cloudy, with a low around 23.
Wednesday
A 30 percent chance of rain. Mostly sunny, with a high near 34.
Wednesday Night
Mostly cloudy, with a low around 28.
Thursday
Mostly cloudy, with a high near 36.
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ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson NY
 40.96°N 73.08°W (Elev. 3 ft)
1:09 pm EST Feb 5, 2026
3pm EST Feb 5, 2026-6pm EST Feb 12, 2026
 
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Additional Resources

Radar & Satellite Image

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Hourly Weather Forecast

National Digital Forecast Database