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

28°F

-2°C

Humidity 51%
Wind Speed W 14 G 25 mph
Barometer 29.87 in (1011.6 mb)
Dewpoint 12°F (-11°C)
Visibility 10.00 mi
Wind Chill17°F (-8°C)
Last update 24 Feb 11:56 am EST
Extended Forecast for

Smithtown NY

  • This Afternoon

    This Afternoon: Mostly sunny, with a high near 32. Wind chill values between 20 and 25. Northwest wind 15 to 17 mph.

    High: 32 °F

    Mostly Sunny

  • Tonight

    Tonight: Snow likely after 4am. Increasing clouds, with a temperature falling to near 19 by 10pm, then rising to around 30 during the remainder of the night. Wind chill values between 10 and 15. West wind 5 to 8 mph becoming light and variable. Chance of precipitation is 60%. New snow accumulation of less than one inch possible.

    Low: 19 °F⇑

    Mostly Clear
    then Snow
    Likely

  • Wednesday

    Wednesday: Snow likely, possibly mixing with rain after 10am, then gradually ending. Cloudy, then gradually becoming mostly sunny, with a high near 39. Wind chill values between 25 and 30. Southwest wind 8 to 10 mph, with gusts as high as 21 mph. Chance of precipitation is 70%. New snow accumulation of less than a half inch possible.

    High: 39 °F

    Rain/Snow
    Likely

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 29. Southwest wind around 6 mph.

    Low: 29 °F

    Partly Cloudy

  • Thursday

    Thursday: A chance of rain and snow after 1pm. Partly sunny, with a high near 37. Light and variable wind becoming west around 6 mph in the morning. Chance of precipitation is 50%.

    High: 37 °F

    Partly Sunny
    then Chance
    Rain/Snow

  • Thursday Night

    Thursday Night: Snow likely, mainly before 1am. Mostly cloudy, with a low around 27. Chance of precipitation is 60%. New snow accumulation of less than a half inch possible.

    Low: 27 °F

    Snow Likely

  • Friday

    Friday: Mostly sunny, with a high near 36.

    High: 36 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 27.

    Low: 27 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 41.

    High: 41 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Mostly sunny, with a high near 32. Wind chill values between 20 and 25. Northwest wind 15 to 17 mph.
Tonight
Snow likely after 4am. Increasing clouds, with a temperature falling to near 19 by 10pm, then rising to around 30 during the remainder of the night. Wind chill values between 10 and 15. West wind 5 to 8 mph becoming light and variable. Chance of precipitation is 60%. New snow accumulation of less than one inch possible.
Wednesday
Snow likely, possibly mixing with rain after 10am, then gradually ending. Cloudy, then gradually becoming mostly sunny, with a high near 39. Wind chill values between 25 and 30. Southwest wind 8 to 10 mph, with gusts as high as 21 mph. Chance of precipitation is 70%. New snow accumulation of less than a half inch possible.
Wednesday Night
Partly cloudy, with a low around 29. Southwest wind around 6 mph.
Thursday
A chance of rain and snow after 1pm. Partly sunny, with a high near 37. Light and variable wind becoming west around 6 mph in the morning. Chance of precipitation is 50%.
Thursday Night
Snow likely, mainly before 1am. Mostly cloudy, with a low around 27. Chance of precipitation is 60%. New snow accumulation of less than a half inch possible.
Friday
Mostly sunny, with a high near 36.
Friday Night
Partly cloudy, with a low around 27.
Saturday
Mostly sunny, with a high near 41.
Saturday Night
Partly cloudy, with a low around 29.
Sunday
Mostly sunny, with a high near 38.
Sunday Night
Partly cloudy, with a low around 16.
Monday
A 30 percent chance of snow. Mostly sunny, with a high near 29.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Smithtown NY
 40.86°N 73.19°W (Elev. 98 ft)
Last Update:
10:52 am EST Feb 24, 2026
Forecast Valid:
12pm EST Feb 24, 2026-6pm EST Mar 2, 2026
 
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