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.

Heavy Rain Fog/Mist

41°F

5°C

Humidity 93%
Wind Speed N 20 G 29 mph
Barometer 29.65 in (1004.2 mb)
Dewpoint 39°F (4°C)
Visibility 2.00 mi
Wind Chill32°F (0°C)
Last update 2 Dec 2:56 pm EST
Extended Forecast for

Smithtown NY

  • This Afternoon

    This Afternoon: Rain. High near 45. Northeast wind around 11 mph. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.

    High: 45 °F

    Rain

  • Tonight

    Tonight: Rain, mainly before 10pm. Low around 30. Northwest wind around 10 mph, with gusts as high as 21 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch possible.

    Low: 30 °F

    Rain then
    Mostly Cloudy

  • Wednesday

    Wednesday: Sunny, with a high near 40. Wind chill values between 25 and 35. Northwest wind 5 to 8 mph.

    High: 40 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 29. Calm wind becoming west around 6 mph after midnight.

    Low: 29 °F

    Mostly Clear

  • Thursday

    Thursday: Partly sunny, with a high near 41. West wind 7 to 14 mph, with gusts as high as 28 mph.

    High: 41 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 18.

    Low: 18 °F

    Mostly Clear

  • Friday

    Friday: Increasing clouds, with a high near 35.

    High: 35 °F

    Increasing
    Clouds

  • Friday Night

    Friday Night: A 40 percent chance of snow. Mostly cloudy, with a low around 26.

    Low: 26 °F

    Chance Snow

  • Saturday

    Saturday: A 30 percent chance of rain before 1pm. Partly sunny, with a high near 42.

    High: 42 °F

    Chance Rain

Detailed Forecast

This Afternoon
Rain. High near 45. Northeast wind around 11 mph. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.
Tonight
Rain, mainly before 10pm. Low around 30. Northwest wind around 10 mph, with gusts as high as 21 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch possible.
Wednesday
Sunny, with a high near 40. Wind chill values between 25 and 35. Northwest wind 5 to 8 mph.
Wednesday Night
Mostly clear, with a low around 29. Calm wind becoming west around 6 mph after midnight.
Thursday
Partly sunny, with a high near 41. West wind 7 to 14 mph, with gusts as high as 28 mph.
Thursday Night
Mostly clear, with a low around 18.
Friday
Increasing clouds, with a high near 35.
Friday Night
A 40 percent chance of snow. Mostly cloudy, with a low around 26.
Saturday
A 30 percent chance of rain before 1pm. Partly sunny, with a high near 42.
Saturday Night
Partly cloudy, with a low around 28.
Sunday
Partly sunny, with a high near 39.
Sunday Night
Mostly cloudy, with a low around 21.
Monday
Partly sunny, with a high near 32.
Monday Night
Partly cloudy, with a low around 18.
Tuesday
Partly sunny, with a high near 35.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Smithtown NY
 40.86°N 73.19°W (Elev. 98 ft)
Last Update:
1:01 pm EST Dec 2, 2025
Forecast Valid:
3pm EST Dec 2, 2025-6pm EST Dec 9, 2025
 
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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