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.

Overcast

75°F

24°C

Humidity 88%
Wind Speed Calm
Barometer 29.88 in (1011.7 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Last update 18 Aug 9:56 am EDT
Extended Forecast for

Islip NYSimilar City Names

  • Today

    Today: Partly sunny, with a high near 84. Light and variable wind becoming southwest around 6 mph in the afternoon.

    High: 84 °F

    Partly Sunny

  • Tonight

    Tonight: Partly cloudy, with a low around 68. Light and variable wind.

    Low: 68 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Sunny, with a high near 86. Calm wind becoming southwest 5 to 9 mph in the afternoon.

    High: 86 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 71. Southwest wind 3 to 7 mph.

    Low: 71 °F

    Partly Cloudy

  • Thursday

    Thursday: A 40 percent chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 83. Light and variable wind becoming southwest 5 to 7 mph in the morning.

    High: 83 °F

    Mostly Sunny
    then Chance
    Showers

  • Thursday Night

    Thursday Night: Showers likely, mainly between 8pm and 2am. Mostly cloudy, with a low around 66. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

    Low: 66 °F

    Showers
    Likely

  • Friday

    Friday: A 30 percent chance of showers before 2pm. Partly sunny, with a high near 81.

    High: 81 °F

    Chance
    Showers

  • Friday Night

    Friday Night: A 30 percent chance of showers after 2am. Mostly cloudy, with a low around 66.

    Low: 66 °F

    Mostly Cloudy
    then Chance
    Showers

  • Saturday

    Saturday: A 50 percent chance of showers. Mostly cloudy, with a high near 80.

    High: 80 °F

    Chance
    Showers

Detailed Forecast

Today
Partly sunny, with a high near 84. Light and variable wind becoming southwest around 6 mph in the afternoon.
Tonight
Partly cloudy, with a low around 68. Light and variable wind.
Wednesday
Sunny, with a high near 86. Calm wind becoming southwest 5 to 9 mph in the afternoon.
Wednesday Night
Partly cloudy, with a low around 71. Southwest wind 3 to 7 mph.
Thursday
A 40 percent chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 83. Light and variable wind becoming southwest 5 to 7 mph in the morning.
Thursday Night
Showers likely, mainly between 8pm and 2am. Mostly cloudy, with a low around 66. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.
Friday
A 30 percent chance of showers before 2pm. Partly sunny, with a high near 81.
Friday Night
A 30 percent chance of showers after 2am. Mostly cloudy, with a low around 66.
Saturday
A 50 percent chance of showers. Mostly cloudy, with a high near 80.
Saturday Night
Showers likely, mainly before 2am. Mostly cloudy, with a low around 66. Chance of precipitation is 60%.
Sunday
A 50 percent chance of showers. Partly sunny, with a high near 81.
Sunday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 65.
Monday
Mostly sunny, with a high near 81.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Islip NYSimilar City Names
 40.73°N 73.22°W (Elev. 7 ft)
Last Update:
5:37 am EDT Aug 18, 2026
Forecast Valid:
10am EDT Aug 18, 2026-6pm EDT Aug 24, 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