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.

A Few Clouds

26°F

-3°C

Humidity 81%
Wind Speed Calm
Barometer 30.20 in (1022.8 mb)
Dewpoint 21°F (-6°C)
Visibility 10.00 mi
Last update 27 Dec 8:56 pm EST
Extended Forecast for

Lake Grove NY

  • Tonight

    Tonight: Mostly clear, with a low around 20. Calm wind.

    Low: 20 °F

    Mostly Clear

  • Sunday

    Sunday: A 20 percent chance of rain after 4pm. Increasing clouds, with a high near 42. Wind chill values between 20 and 30. Calm wind becoming west around 6 mph in the morning.

    High: 42 °F

    Mostly Sunny
    then Slight
    Chance Rain

  • Sunday Night

    Sunday Night: Rain, mainly after 7pm. Temperature rising to around 41 by 2am. South wind 3 to 7 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.

    Low: 35 °F⇑

    Rain

  • Monday

    Monday: Rain, mainly before 1pm. High near 50. Southwest wind 9 to 15 mph, with gusts as high as 28 mph. Chance of precipitation is 90%. New precipitation amounts of less than a tenth of an inch possible.

    High: 50 °F

    Rain

  • Monday Night

    Monday Night: A slight chance of rain showers before 10pm, then a slight chance of snow showers between 10pm and 1am. Mostly cloudy, with a low around 25. West wind 16 to 18 mph, with gusts as high as 34 mph. Chance of precipitation is 20%.

    Low: 25 °F

    Slight Chance
    Rain/Snow
    then Slight
    Chance Snow
    Showers

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 33. Breezy.

    High: 33 °F

    Mostly Cloudy
    and Breezy

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 24.

    Low: 24 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 35.

    High: 35 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 25.

    Low: 25 °F

    Partly Cloudy

Detailed Forecast

Tonight
Mostly clear, with a low around 20. Calm wind.
Sunday
A 20 percent chance of rain after 4pm. Increasing clouds, with a high near 42. Wind chill values between 20 and 30. Calm wind becoming west around 6 mph in the morning.
Sunday Night
Rain, mainly after 7pm. Temperature rising to around 41 by 2am. South wind 3 to 7 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.
Monday
Rain, mainly before 1pm. High near 50. Southwest wind 9 to 15 mph, with gusts as high as 28 mph. Chance of precipitation is 90%. New precipitation amounts of less than a tenth of an inch possible.
Monday Night
A slight chance of rain showers before 10pm, then a slight chance of snow showers between 10pm and 1am. Mostly cloudy, with a low around 25. West wind 16 to 18 mph, with gusts as high as 34 mph. Chance of precipitation is 20%.
Tuesday
Mostly cloudy, with a high near 33. Breezy.
Tuesday Night
Mostly cloudy, with a low around 24.
Wednesday
Mostly sunny, with a high near 35.
Wednesday Night
Partly cloudy, with a low around 25.
New Year's Day
A 30 percent chance of snow. Mostly cloudy, with a high near 35.
Thursday Night
A 30 percent chance of snow. Mostly cloudy, with a low around 19.
Friday
Mostly sunny, with a high near 30.
Friday Night
Partly cloudy, with a low around 20.
Saturday
Mostly sunny, with a high near 34.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Lake Grove NY
 40.85°N 73.1°W (Elev. 144 ft)
Last Update:
12:59 pm EST Dec 27, 2025
Forecast Valid:
9pm EST Dec 27, 2025-6pm EST Jan 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