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.

Mostly Cloudy

55°F

13°C

Humidity 87%
Wind Speed S 15 G 29 mph
Barometer 29.78 in (1008.4 mb)
Dewpoint 51°F (11°C)
Visibility 9.00 mi
Wind Chill51°F (11°C)
Last update 11 Mar 5:56 pm EDT
Extended Forecast for

Islandia NY

  • Tonight

    Tonight: A chance of showers and thunderstorms. Mostly cloudy, with a low around 41. Southwest wind around 10 mph, with gusts as high as 24 mph. Chance of precipitation is 50%.

    Low: 41 °F

    Chance
    Showers

  • Thursday

    Thursday: Showers, mainly before 5pm. High near 54. West wind 10 to 15 mph becoming northwest in the afternoon. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch possible.

    High: 54 °F

    Showers

  • Thursday Night

    Thursday Night: A 30 percent chance of showers before 8pm. Mostly cloudy, then gradually becoming mostly clear, with a low around 30. West wind 6 to 9 mph.

    Low: 30 °F

    Chance
    Showers then
    Mostly Clear

  • Friday

    Friday: Increasing clouds, with a high near 45. Light and variable wind becoming south 10 to 15 mph in the morning.

    High: 45 °F

    Increasing
    Clouds

  • Friday Night

    Friday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 37. South wind 9 to 13 mph, with gusts as high as 25 mph.

    Low: 37 °F

    Decreasing
    Clouds

  • Saturday

    Saturday: Sunny, with a high near 49.

    High: 49 °F

    Sunny

  • Saturday Night

    Saturday Night: Increasing clouds, with a low around 32.

    Low: 32 °F

    Increasing
    Clouds

  • Sunday

    Sunday: Cloudy, with a high near 48.

    High: 48 °F

    Cloudy

  • Sunday Night

    Sunday Night: Showers, mainly after 2am. Low around 39. Chance of precipitation is 80%.

    Low: 39 °F

    Chance
    Showers then
    Showers

Detailed Forecast

Tonight
A chance of showers and thunderstorms. Mostly cloudy, with a low around 41. Southwest wind around 10 mph, with gusts as high as 24 mph. Chance of precipitation is 50%.
Thursday
Showers, mainly before 5pm. High near 54. West wind 10 to 15 mph becoming northwest in the afternoon. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch possible.
Thursday Night
A 30 percent chance of showers before 8pm. Mostly cloudy, then gradually becoming mostly clear, with a low around 30. West wind 6 to 9 mph.
Friday
Increasing clouds, with a high near 45. Light and variable wind becoming south 10 to 15 mph in the morning.
Friday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 37. South wind 9 to 13 mph, with gusts as high as 25 mph.
Saturday
Sunny, with a high near 49.
Saturday Night
Increasing clouds, with a low around 32.
Sunday
Cloudy, with a high near 48.
Sunday Night
Showers, mainly after 2am. Low around 39. Chance of precipitation is 80%.
Monday
Showers. High near 54. Chance of precipitation is 90%.
Monday Night
Showers likely. Mostly cloudy, with a low around 30. Chance of precipitation is 60%.
Tuesday
A 30 percent chance of showers. Partly sunny, with a high near 38.
Tuesday Night
Mostly clear, with a low around 23.
Wednesday
Mostly sunny, with a high near 36.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Islandia NY
 40.81°N 73.17°W (Elev. 161 ft)
Last Update:
3:16 pm EDT Mar 11, 2026
Forecast Valid:
6pm EDT Mar 11, 2026-6pm EDT Mar 18, 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