National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

A Few Clouds

37°F

3°C

Humidity 93%
Wind Speed Calm
Barometer 30.02 in (1016.5 mb)
Dewpoint 35°F (2°C)
Visibility 10.00 mi
Last update 9 Mar 7:56 am EDT
Extended Forecast for

Port Jefferson Station NY

  • Today

    Today: Sunny, with a high near 61. Calm wind becoming southwest 5 to 9 mph in the morning.

    High: 61 °F

    Sunny

  • Tonight

    Tonight: Patchy fog after 2am. Otherwise, partly cloudy, with a low around 38. South wind 3 to 7 mph.

    Low: 38 °F

    Mostly Clear
    then Patchy
    Fog

  • Tuesday

    Tuesday: Patchy fog before 8am. Otherwise, mostly sunny, with a high near 60. Calm wind becoming southwest 5 to 7 mph in the morning.

    High: 60 °F

    Patchy Fog
    then Mostly
    Sunny

  • Tuesday Night

    Tuesday Night: Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 40. Light south wind.

    Low: 40 °F

    Partly Cloudy
    then Patchy
    Fog

  • Wednesday

    Wednesday: A 20 percent chance of showers after 2pm. Patchy fog before 8am. Otherwise, mostly cloudy, with a high near 54. South wind 5 to 10 mph.

    High: 54 °F

    Patchy Fog
    then Slight
    Chance
    Showers

  • Wednesday Night

    Wednesday Night: A 50 percent chance of rain. Mostly cloudy, with a low around 47.

    Low: 47 °F

    Chance Rain

  • Thursday

    Thursday: Rain likely before 2pm, then a chance of rain and snow. Mostly cloudy, with a high near 53. Chance of precipitation is 60%.

    High: 53 °F

    Rain Likely
    then
    Rain/Snow
    Likely

  • Thursday Night

    Thursday Night: A chance of rain and snow before 8pm. Partly cloudy, with a low around 29. Chance of precipitation is 30%.

    Low: 29 °F

    Chance
    Rain/Snow
    then Mostly
    Clear

  • Friday

    Friday: Partly sunny, with a high near 43.

    High: 43 °F

    Partly Sunny

Detailed Forecast

Today
Sunny, with a high near 61. Calm wind becoming southwest 5 to 9 mph in the morning.
Tonight
Patchy fog after 2am. Otherwise, partly cloudy, with a low around 38. South wind 3 to 7 mph.
Tuesday
Patchy fog before 8am. Otherwise, mostly sunny, with a high near 60. Calm wind becoming southwest 5 to 7 mph in the morning.
Tuesday Night
Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 40. Light south wind.
Wednesday
A 20 percent chance of showers after 2pm. Patchy fog before 8am. Otherwise, mostly cloudy, with a high near 54. South wind 5 to 10 mph.
Wednesday Night
A 50 percent chance of rain. Mostly cloudy, with a low around 47.
Thursday
Rain likely before 2pm, then a chance of rain and snow. Mostly cloudy, with a high near 53. Chance of precipitation is 60%.
Thursday Night
A chance of rain and snow before 8pm. Partly cloudy, with a low around 29. Chance of precipitation is 30%.
Friday
Partly sunny, with a high near 43.
Friday Night
A 40 percent chance of rain after 8pm. Mostly cloudy, with a low around 34.
Saturday
Mostly sunny, with a high near 45.
Saturday Night
Mostly cloudy, with a low around 32.
Sunday
A chance of rain and snow. Cloudy, with a high near 47. Chance of precipitation is 30%.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson Station NY
 40.93°N 73.06°W (Elev. 161 ft)
Last Update:
7:50 am EDT Mar 9, 2026
Forecast Valid:
8am EDT Mar 9, 2026-6pm EDT Mar 15, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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