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

79°F

26°C

Humidity 49%
Wind Speed SW 18 G 30 mph
Barometer 29.58 in (1001.4 mb)
Dewpoint 58°F (14°C)
Visibility 10.00 mi
Heat Index80°F (27°C)
Last update 18 Jun 10:56 pm EDT
Extended Forecast for

Port Jefferson Station NY

  • Tonight

    Tonight: Mostly cloudy, with a low around 69. West wind around 14 mph.

    Low: 69 °F

    Mostly Cloudy

  • Juneteenth

    Juneteenth: Mostly cloudy, then gradually becoming sunny, with a high near 84. West wind 11 to 17 mph, with gusts as high as 29 mph.

    High: 84 °F

    Decreasing
    Clouds

  • Friday Night

    Friday Night: Clear, with a low around 65. West wind 10 to 13 mph.

    Low: 65 °F

    Clear

  • Saturday

    Saturday: Sunny, with a high near 82. Breezy, with a west wind 17 to 20 mph, with gusts as high as 31 mph.

    High: 82 °F

    Sunny and
    Breezy then
    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 66. Northwest wind 7 to 9 mph.

    Low: 66 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 83.

    High: 83 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 66.

    Low: 66 °F

    Partly Cloudy

  • Monday

    Monday: Showers, mainly after 2pm. High near 79. Chance of precipitation is 80%.

    High: 79 °F

    Chance
    Showers then
    Showers

  • Monday Night

    Monday Night: Showers, mainly before 2am. Low around 66. Chance of precipitation is 80%.

    Low: 66 °F

    Showers

Detailed Forecast

Tonight
Mostly cloudy, with a low around 69. West wind around 14 mph.
Juneteenth
Mostly cloudy, then gradually becoming sunny, with a high near 84. West wind 11 to 17 mph, with gusts as high as 29 mph.
Friday Night
Clear, with a low around 65. West wind 10 to 13 mph.
Saturday
Sunny, with a high near 82. Breezy, with a west wind 17 to 20 mph, with gusts as high as 31 mph.
Saturday Night
Mostly clear, with a low around 66. Northwest wind 7 to 9 mph.
Sunday
Sunny, with a high near 83.
Sunday Night
Partly cloudy, with a low around 66.
Monday
Showers, mainly after 2pm. High near 79. Chance of precipitation is 80%.
Monday Night
Showers, mainly before 2am. Low around 66. Chance of precipitation is 80%.
Tuesday
A 30 percent chance of showers before 2pm. Partly sunny, with a high near 83.
Tuesday Night
Partly cloudy, with a low around 67.
Wednesday
Sunny, with a high near 84.
Wednesday Night
Partly cloudy, with a low around 67.
Thursday
Mostly sunny, with a high near 83.
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:
4:34 pm EDT Jun 18, 2026
Forecast Valid:
11pm EDT Jun 18, 2026-6pm EDT Jun 25, 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