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

49°F

9°C

Humidity 83%
Wind Speed SW 7 mph
Barometer 30.07 in (1018.1 mb)
Dewpoint 44°F (7°C)
Visibility 9.00 mi
Wind Chill46°F (8°C)
Last update 31 Mar 1:56 am EDT
Extended Forecast for

Lake Grove NY

  • Overnight

    Overnight: Showers likely. Mostly cloudy, with a low around 49. Southwest wind around 9 mph. Chance of precipitation is 60%.

    Low: 49 °F

    Showers
    Likely

  • Tuesday

    Tuesday: Showers likely, mainly before 11am. Partly sunny, with a high near 65. Southwest wind 13 to 15 mph. Chance of precipitation is 60%.

    High: 65 °F

    Showers
    Likely then
    Slight Chance
    Showers

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers, mainly after 5am. Mostly cloudy, with a low around 52. Southwest wind around 14 mph.

    Low: 52 °F

    Partly Cloudy
    then Chance
    Showers

  • Wednesday

    Wednesday: A chance of showers before 8am, then a chance of rain between 8am and 2pm, then rain likely and possibly a thunderstorm after 2pm. Mostly cloudy, with a high near 66. Southwest wind 10 to 13 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 66 °F

    Chance Rain
    then Rain
    Likely

  • Wednesday Night

    Wednesday Night: Rain and possibly a thunderstorm. Low around 41. Northeast wind 7 to 11 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 41 °F

    Rain

  • Thursday

    Thursday: A 30 percent chance of rain before 2pm. Cloudy, with a high near 46.

    High: 46 °F

    Chance Rain

  • Thursday Night

    Thursday Night: A chance of rain between 8pm and 2am. Cloudy, with a low around 39. Chance of precipitation is 30%.

    Low: 39 °F

    Chance Rain

  • Friday

    Friday: Mostly cloudy, with a high near 59.

    High: 59 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 49.

    Low: 49 °F

    Mostly Cloudy

Detailed Forecast

Overnight
Showers likely. Mostly cloudy, with a low around 49. Southwest wind around 9 mph. Chance of precipitation is 60%.
Tuesday
Showers likely, mainly before 11am. Partly sunny, with a high near 65. Southwest wind 13 to 15 mph. Chance of precipitation is 60%.
Tuesday Night
A 30 percent chance of showers, mainly after 5am. Mostly cloudy, with a low around 52. Southwest wind around 14 mph.
Wednesday
A chance of showers before 8am, then a chance of rain between 8am and 2pm, then rain likely and possibly a thunderstorm after 2pm. Mostly cloudy, with a high near 66. Southwest wind 10 to 13 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
Rain and possibly a thunderstorm. Low around 41. Northeast wind 7 to 11 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Thursday
A 30 percent chance of rain before 2pm. Cloudy, with a high near 46.
Thursday Night
A chance of rain between 8pm and 2am. Cloudy, with a low around 39. Chance of precipitation is 30%.
Friday
Mostly cloudy, with a high near 59.
Friday Night
Mostly cloudy, with a low around 49.
Saturday
Partly sunny, with a high near 64.
Saturday Night
A 30 percent chance of rain. Mostly cloudy, with a low around 47.
Sunday
A 40 percent chance of rain. Mostly cloudy, with a high near 61.
Sunday Night
A 50 percent chance of rain. Mostly cloudy, with a low around 43.
Monday
A 30 percent chance of rain. Partly sunny, with a high near 52.
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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:
2:46 am EDT Mar 31, 2026
Forecast Valid:
2am EDT Mar 31, 2026-6pm EDT Apr 6, 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