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Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Mostly Cloudy

26°F

-3°C

Humidity 57%
Wind Speed W 6 mph
Barometer 30.18 in (1022.2 mb)
Dewpoint 13°F (-11°C)
Visibility 10.00 mi
Wind Chill19°F (-7°C)
Last update 15 Dec 6:56 pm EST
Extended Forecast for

Smithtown NY

  • Tonight

    Tonight: Mostly cloudy, with a low around 19. Wind chill values between 10 and 15. West wind around 7 mph.

    Low: 19 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 32. Wind chill values between 15 and 25. Southwest wind around 6 mph.

    High: 32 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 23. Southwest wind 3 to 6 mph.

    Low: 23 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 42. Wind chill values between 20 and 30. Southwest wind 7 to 11 mph, with gusts as high as 22 mph.

    High: 42 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 26. West wind around 6 mph becoming calm in the evening.

    Low: 26 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 53.

    High: 53 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Rain, mainly after 1am. Low around 40. Chance of precipitation is 90%.

    Low: 40 °F

    Chance Rain
    then Rain

  • Friday

    Friday: Rain likely before 1pm. Partly sunny, with a high near 53. Chance of precipitation is 60%.

    High: 53 °F

    Rain Likely

  • Friday Night

    Friday Night: Partly cloudy, with a low around 24.

    Low: 24 °F

    Partly Cloudy

Detailed Forecast

Tonight
Mostly cloudy, with a low around 19. Wind chill values between 10 and 15. West wind around 7 mph.
Tuesday
Sunny, with a high near 32. Wind chill values between 15 and 25. Southwest wind around 6 mph.
Tuesday Night
Partly cloudy, with a low around 23. Southwest wind 3 to 6 mph.
Wednesday
Mostly sunny, with a high near 42. Wind chill values between 20 and 30. Southwest wind 7 to 11 mph, with gusts as high as 22 mph.
Wednesday Night
Partly cloudy, with a low around 26. West wind around 6 mph becoming calm in the evening.
Thursday
Mostly sunny, with a high near 53.
Thursday Night
Rain, mainly after 1am. Low around 40. Chance of precipitation is 90%.
Friday
Rain likely before 1pm. Partly sunny, with a high near 53. Chance of precipitation is 60%.
Friday Night
Partly cloudy, with a low around 24.
Saturday
Partly sunny, with a high near 41.
Saturday Night
Mostly cloudy, with a low around 31.
Sunday
Partly sunny, with a high near 46.
Sunday Night
Partly cloudy, with a low around 28.
Monday
Partly sunny, with a high near 40.
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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:
6:41 pm EST Dec 15, 2025
Forecast Valid:
7pm EST Dec 15, 2025-6pm EST Dec 22, 2025
 
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