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.

Mostly Cloudy

36°F

2°C

Humidity 59%
Wind Speed Calm
Barometer 30.27 in (1025.2 mb)
Dewpoint 23°F (-5°C)
Visibility 10.00 mi
Last update 24 Dec 9:56 pm EST
Extended Forecast for

Lake Ronkonkoma NY

Winter Storm Watch December 26, 04:00pm until December 27, 01:00pm
Click here for hazard details and duration
Winter Storm Watch

  • Tonight

    Tonight: Increasing clouds, with a low around 27. Calm wind.

    Low: 27 °F

    Increasing
    Clouds

  • Christmas Day

    Christmas Day: Partly sunny, with a high near 44. Southwest wind 6 to 11 mph becoming west 12 to 17 mph in the afternoon. Winds could gust as high as 29 mph.

    High: 44 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 20. Wind chill values between 5 and 15. North wind 14 to 17 mph, with gusts as high as 29 mph.

    Low: 20 °F

    Partly Cloudy

  • Friday

    Friday: A 30 percent chance of snow after 1pm. Increasing clouds, with a high near 29. Wind chill values between 5 and 15. North wind 5 to 11 mph.

    High: 29 °F

    Partly Sunny
    then Chance
    Snow

  • Friday Night

    Friday Night: Snow. Low around 22. Calm wind becoming east 5 to 8 mph in the evening. Chance of precipitation is 90%. New snow accumulation of 3 to 7 inches possible.

    Low: 22 °F

    Snow

  • Saturday

    Saturday: A 50 percent chance of snow before 1pm. Cloudy, with a high near 33.

    High: 33 °F

    Chance Snow

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 22.

    Low: 22 °F

    Mostly Cloudy

  • Sunday

    Sunday: A 30 percent chance of rain after 1pm. Mostly cloudy, with a high near 39.

    High: 39 °F

    Mostly Cloudy
    then Chance
    Rain

  • Sunday Night

    Sunday Night: Rain. Low around 29. Chance of precipitation is 80%.

    Low: 29 °F

    Rain

Detailed Forecast

Tonight
Increasing clouds, with a low around 27. Calm wind.
Christmas Day
Partly sunny, with a high near 44. Southwest wind 6 to 11 mph becoming west 12 to 17 mph in the afternoon. Winds could gust as high as 29 mph.
Thursday Night
Partly cloudy, with a low around 20. Wind chill values between 5 and 15. North wind 14 to 17 mph, with gusts as high as 29 mph.
Friday
A 30 percent chance of snow after 1pm. Increasing clouds, with a high near 29. Wind chill values between 5 and 15. North wind 5 to 11 mph.
Friday Night
Snow. Low around 22. Calm wind becoming east 5 to 8 mph in the evening. Chance of precipitation is 90%. New snow accumulation of 3 to 7 inches possible.
Saturday
A 50 percent chance of snow before 1pm. Cloudy, with a high near 33.
Saturday Night
Mostly cloudy, with a low around 22.
Sunday
A 30 percent chance of rain after 1pm. Mostly cloudy, with a high near 39.
Sunday Night
Rain. Low around 29. Chance of precipitation is 80%.
Monday
Rain likely, mainly before 1pm. Mostly cloudy, with a high near 44. Chance of precipitation is 60%.
Monday Night
Mostly cloudy, with a low around 23.
Tuesday
Partly sunny, with a high near 32.
Tuesday Night
Partly cloudy, with a low around 22.
Wednesday
Partly sunny, with a high near 36.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Lake Ronkonkoma NY
 40.83°N 73.11°W (Elev. 98 ft)
Last Update:
10:07 pm EST Dec 24, 2025
Forecast Valid:
10pm EST Dec 24, 2025-6pm EST Dec 31, 2025
 
Forecast Discussion
 
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Additional Resources

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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