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.

Light Rain Fog/Mist

36°F

2°C

Humidity 93%
Wind Speed E 7 mph
Barometer 29.87 in (1011.6 mb)
Dewpoint 34°F (1°C)
Visibility 6.00 mi
Wind Chill30°F (-1°C)
Last update 20 Feb 8:56 am EST
Extended Forecast for

Port Jefferson NY

  • Today

    Today: Rain. High near 37. East wind 14 to 18 mph. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.

    High: 37 °F

    Rain

  • Tonight

    Tonight: Rain likely, mainly before 7pm. Mostly cloudy, with a low around 34. Northeast wind 7 to 11 mph becoming west after midnight. Chance of precipitation is 60%.

    Low: 34 °F

    Rain Likely
    then Mostly
    Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 41. West wind around 8 mph.

    High: 41 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: A slight chance of rain and snow before 1am, then a slight chance of snow. Cloudy, with a low around 33. East wind 7 to 11 mph. Chance of precipitation is 20%.

    Low: 33 °F

    Slight Chance
    Rain/Snow

  • Sunday

    Sunday: A 50 percent chance of snow. Cloudy, with a high near 36. Breezy, with an east wind 17 to 22 mph.

    High: 36 °F

    Chance Snow
    and Breezy

  • Sunday Night

    Sunday Night: Snow likely. Cloudy, with a low around 32. Windy. Chance of precipitation is 60%. New snow accumulation of 2 to 4 inches possible.

    Low: 32 °F

    Snow Likely
    and Windy

  • Monday

    Monday: A 40 percent chance of snow before 1pm. Cloudy, with a high near 35. Windy.

    High: 35 °F

    Chance Snow
    and Windy

  • Monday Night

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

    Low: 28 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 35.

    High: 35 °F

    Mostly Sunny

Detailed Forecast

Today
Rain. High near 37. East wind 14 to 18 mph. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.
Tonight
Rain likely, mainly before 7pm. Mostly cloudy, with a low around 34. Northeast wind 7 to 11 mph becoming west after midnight. Chance of precipitation is 60%.
Saturday
Partly sunny, with a high near 41. West wind around 8 mph.
Saturday Night
A slight chance of rain and snow before 1am, then a slight chance of snow. Cloudy, with a low around 33. East wind 7 to 11 mph. Chance of precipitation is 20%.
Sunday
A 50 percent chance of snow. Cloudy, with a high near 36. Breezy, with an east wind 17 to 22 mph.
Sunday Night
Snow likely. Cloudy, with a low around 32. Windy. Chance of precipitation is 60%. New snow accumulation of 2 to 4 inches possible.
Monday
A 40 percent chance of snow before 1pm. Cloudy, with a high near 35. Windy.
Monday Night
Mostly cloudy, with a low around 28.
Tuesday
Mostly sunny, with a high near 35.
Tuesday Night
Mostly cloudy, with a low around 26.
Wednesday
Mostly cloudy, with a high near 39.
Wednesday Night
Rain likely. Cloudy, with a low around 36. Breezy. Chance of precipitation is 60%.
Thursday
A 40 percent chance of rain. Mostly cloudy, with a high near 42.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson NY
 40.96°N 73.08°W (Elev. 3 ft)
Last Update:
1:01 am EST Feb 20, 2026
Forecast Valid:
9am EST Feb 20, 2026-6pm EST Feb 26, 2026
 
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Additional Resources

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Hourly Weather Forecast

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation