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Hazardous Weather Conditions

Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Fair

14°F

-10°C

Humidity 47%
Wind Speed N 18 G 30 mph
Barometer 30.18 in (1022.0 mb)
Dewpoint -3°F (-19°C)
Visibility 10.00 mi
Wind Chill-3°F (-19°C)
Last update 8 Feb 10:56 pm EST
Extended Forecast for

Port Jefferson NY

Cold Weather Advisory February 8, 11:10pm until February 9, 10:00am
Click here for hazard details and duration
Cold Weather Advisory
  •  
    Cold Weather Advisory February 8, 11:10pm until February 9, 10:00am

    NOW until 10:00am Mon

    Cold Weather Advisory

  • Tonight

    Low: 9 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 27. Wind chill values between -5 and 5. Northwest wind 8 to 10 mph.

    High: 27 °F

    Sunny

  • Monday Night

    Monday Night: Increasing clouds, with a low around 17. Northwest wind around 5 mph becoming calm in the evening.

    Low: 17 °F

    Increasing
    Clouds

  • Tuesday

    Tuesday: A chance of snow after 1pm, mixing with rain after 4pm. Mostly cloudy, with a high near 34. Wind chill values between 20 and 30. Calm wind becoming southwest around 6 mph in the afternoon. Chance of precipitation is 30%.

    High: 34 °F

    Partly Sunny
    then Chance
    Rain/Snow

  • Tuesday Night

    Tuesday Night: A chance of rain and snow before 7pm, then a chance of snow between 7pm and 1am. Cloudy, then gradually becoming partly cloudy, with a low around 27. Calm wind becoming west around 6 mph after midnight. Chance of precipitation is 30%.

    Low: 27 °F

    Chance
    Rain/Snow
    then Chance
    Snow

  • Wednesday

    Wednesday: Mostly sunny, with a high near 36.

    High: 36 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 22.

    Low: 22 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 33.

    High: 33 °F

    Mostly Sunny

Detailed Forecast

Tonight
Mostly clear, with a low around 9. Wind chill values between -5 and zero. Northwest wind around 11 mph.
Monday
Sunny, with a high near 27. Wind chill values between -5 and 5. Northwest wind 8 to 10 mph.
Monday Night
Increasing clouds, with a low around 17. Northwest wind around 5 mph becoming calm in the evening.
Tuesday
A chance of snow after 1pm, mixing with rain after 4pm. Mostly cloudy, with a high near 34. Wind chill values between 20 and 30. Calm wind becoming southwest around 6 mph in the afternoon. Chance of precipitation is 30%.
Tuesday Night
A chance of rain and snow before 7pm, then a chance of snow between 7pm and 1am. Cloudy, then gradually becoming partly cloudy, with a low around 27. Calm wind becoming west around 6 mph after midnight. Chance of precipitation is 30%.
Wednesday
Mostly sunny, with a high near 36.
Wednesday Night
Partly cloudy, with a low around 22.
Thursday
Mostly sunny, with a high near 33.
Thursday Night
Partly cloudy, with a low around 20.
Friday
Mostly sunny, with a high near 32.
Friday Night
Partly cloudy, with a low around 20.
Saturday
Sunny, with a high near 34.
Saturday Night
Partly cloudy, with a low around 23.
Sunday
A 30 percent chance of rain. Partly sunny, with a high near 38.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson NY
 40.93°N 73.06°W (Elev. 161 ft)
Last Update:
5:59 pm EST Feb 8, 2026
Forecast Valid:
11pm EST Feb 8, 2026-6pm EST Feb 15, 2026
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation