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Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Mostly Cloudy

72°F

22°C

Humidity 97%
Wind Speed Calm
Barometer 29.63 in (1003.2 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Last update 29 Jul 9:56 pm EDT
Extended Forecast for

Lake Grove NY

  • Tonight

    Tonight: A chance of showers and thunderstorms. Mostly cloudy, with a low around 67. Light and variable wind. Chance of precipitation is 30%.

    Low: 67 °F

    Chance
    T-storms then
    Chance
    Showers

  • Thursday

    Thursday: A chance of showers, with thunderstorms also possible after 11am. Mostly cloudy, with a high near 75. North wind 5 to 11 mph. Chance of precipitation is 50%.

    High: 75 °F

    Chance
    Showers

  • Thursday Night

    Thursday Night: Mostly cloudy, then gradually becoming clear, with a low around 63. North wind 5 to 8 mph.

    Low: 63 °F

    Decreasing
    Clouds

  • Friday

    Friday: Sunny, with a high near 82. Northwest wind around 6 mph.

    High: 82 °F

    Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 66. South wind around 5 mph becoming calm in the evening.

    Low: 66 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 82.

    High: 82 °F

    Partly Sunny

  • Saturday Night

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

    Low: 68 °F

    Mostly Cloudy

  • Sunday

    Sunday: Mostly cloudy, with a high near 81.

    High: 81 °F

    Mostly Cloudy

  • Sunday Night

    Sunday Night: A 50 percent chance of showers. Mostly cloudy, with a low around 67.

    Low: 67 °F

    Chance
    Showers

Detailed Forecast

Tonight
A chance of showers and thunderstorms. Mostly cloudy, with a low around 67. Light and variable wind. Chance of precipitation is 30%.
Thursday
A chance of showers, with thunderstorms also possible after 11am. Mostly cloudy, with a high near 75. North wind 5 to 11 mph. Chance of precipitation is 50%.
Thursday Night
Mostly cloudy, then gradually becoming clear, with a low around 63. North wind 5 to 8 mph.
Friday
Sunny, with a high near 82. Northwest wind around 6 mph.
Friday Night
Partly cloudy, with a low around 66. South wind around 5 mph becoming calm in the evening.
Saturday
Partly sunny, with a high near 82.
Saturday Night
Mostly cloudy, with a low around 68.
Sunday
Mostly cloudy, with a high near 81.
Sunday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 67.
Monday
A 40 percent chance of showers. Partly sunny, with a high near 82.
Monday Night
Partly cloudy, with a low around 67.
Tuesday
Sunny, with a high near 82.
Tuesday Night
Mostly clear, with a low around 66.
Wednesday
Sunny, with a high near 83.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Lake Grove NY
 40.85°N 73.1°W (Elev. 144 ft)
Last Update:
9:30 pm EDT Jul 29, 2026
Forecast Valid:
10pm EDT Jul 29, 2026-6pm EDT Aug 5, 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