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

73°F

23°C

Humidity 100%
Wind Speed Calm
Barometer 29.98 in (1015.2 mb)
Dewpoint 73°F (23°C)
Visibility 5.00 mi
Last update 28 Aug 7:56 am EDT
Extended Forecast for

Port Jefferson Station NY

  • Today

    Today: A slight chance of showers between 11am and 2pm, then a chance of showers and thunderstorms after 2pm. Patchy fog before 11am. Otherwise, partly sunny, with a high near 81. Calm wind becoming west around 5 mph in the morning. Chance of precipitation is 40%.

    High: 81 °F

    Slight Chance
    Showers and
    Patchy Fog
    then Chance
    T-storms

  • Tonight

    Tonight: A 30 percent chance of showers and thunderstorms before 8pm. Mostly cloudy, with a low around 62. Light and variable wind becoming north 5 to 8 mph after midnight.

    Low: 62 °F

    Chance
    T-storms then
    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 77. North wind 3 to 8 mph.

    High: 77 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 63. Light south wind.

    Low: 63 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 80. Light west wind becoming southwest 5 to 10 mph in the morning.

    High: 80 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 68.

    Low: 68 °F

    Mostly Cloudy

  • Monday

    Monday: Partly sunny, with a high near 81.

    High: 81 °F

    Partly Sunny

  • Monday Night

    Monday Night: A 30 percent chance of showers after 2am. Mostly cloudy, with a low around 67.

    Low: 67 °F

    Mostly Cloudy
    then Chance
    Showers

  • Tuesday

    Tuesday: A 50 percent chance of showers. Mostly cloudy, with a high near 79.

    High: 79 °F

    Chance
    Showers

Detailed Forecast

Today
A slight chance of showers between 11am and 2pm, then a chance of showers and thunderstorms after 2pm. Patchy fog before 11am. Otherwise, partly sunny, with a high near 81. Calm wind becoming west around 5 mph in the morning. Chance of precipitation is 40%.
Tonight
A 30 percent chance of showers and thunderstorms before 8pm. Mostly cloudy, with a low around 62. Light and variable wind becoming north 5 to 8 mph after midnight.
Saturday
Mostly sunny, with a high near 77. North wind 3 to 8 mph.
Saturday Night
Mostly clear, with a low around 63. Light south wind.
Sunday
Sunny, with a high near 80. Light west wind becoming southwest 5 to 10 mph in the morning.
Sunday Night
Mostly cloudy, with a low around 68.
Monday
Partly sunny, with a high near 81.
Monday Night
A 30 percent chance of showers after 2am. Mostly cloudy, with a low around 67.
Tuesday
A 50 percent chance of showers. Mostly cloudy, with a high near 79.
Tuesday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 67.
Wednesday
A 50 percent chance of showers. Partly sunny, with a high near 79.
Wednesday Night
A 40 percent chance of showers. Mostly cloudy, with a low around 67.
Thursday
Partly sunny, with a high near 80.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Port Jefferson Station NY
 40.93°N 73.06°W (Elev. 161 ft)
Last Update:
4:20 am EDT Aug 28, 2026
Forecast Valid:
8am EDT Aug 28, 2026-6pm EDT Sep 3, 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