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

55°F

13°C

Humidity 74%
Wind Speed SE 5 mph
Barometer 30.18 in (1021.9 mb)
Dewpoint 47°F (8°C)
Visibility 10.00 mi
Wind Chill54°F (12°C)
Last update 15 Oct 7:56 pm EDT
Extended Forecast for

Smithtown NY

  • Tonight

    Tonight: Showers likely after 5am. Increasing clouds, with a low around 51. Southeast wind 3 to 6 mph. Chance of precipitation is 60%.

    Low: 51 °F

    Partly Cloudy
    then Showers
    Likely

  • Friday

    Friday: Showers, with thunderstorms also possible after 2pm. High near 72. Southwest wind 10 to 13 mph, with gusts as high as 23 mph. Chance of precipitation is 90%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 72 °F

    Showers then
    Chance
    Showers

  • Friday Night

    Friday Night: Showers and thunderstorms before 2am, then showers likely. Low around 44. West wind 8 to 11 mph, with gusts as high as 21 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 44 °F

    Showers then
    Showers
    Likely

  • Saturday

    Saturday: Showers likely before 8am. Cloudy, then gradually becoming mostly sunny, with a high near 54. North wind around 16 mph, with gusts as high as 28 mph. Chance of precipitation is 60%.

    High: 54 °F

    Showers
    Likely then
    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 39. North wind 8 to 13 mph.

    Low: 39 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 56.

    High: 56 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 43.

    Low: 43 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 61.

    High: 61 °F

    Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 45.

    Low: 45 °F

    Partly Cloudy

Detailed Forecast

Tonight
Showers likely after 5am. Increasing clouds, with a low around 51. Southeast wind 3 to 6 mph. Chance of precipitation is 60%.
Friday
Showers, with thunderstorms also possible after 2pm. High near 72. Southwest wind 10 to 13 mph, with gusts as high as 23 mph. Chance of precipitation is 90%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Friday Night
Showers and thunderstorms before 2am, then showers likely. Low around 44. West wind 8 to 11 mph, with gusts as high as 21 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Saturday
Showers likely before 8am. Cloudy, then gradually becoming mostly sunny, with a high near 54. North wind around 16 mph, with gusts as high as 28 mph. Chance of precipitation is 60%.
Saturday Night
Mostly clear, with a low around 39. North wind 8 to 13 mph.
Sunday
Sunny, with a high near 56.
Sunday Night
Mostly clear, with a low around 43.
Monday
Sunny, with a high near 61.
Monday Night
Partly cloudy, with a low around 45.
Tuesday
Mostly sunny, with a high near 64.
Tuesday Night
Partly cloudy, with a low around 48.
Wednesday
Sunny, with a high near 64.
Wednesday Night
Mostly clear, with a low around 45.
Thursday
Mostly sunny, with a high near 60.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Smithtown NY
 40.86°N 73.22°W (Elev. 82 ft)
Last Update:
2:36 pm EDT Oct 15, 2026
Forecast Valid:
8pm EDT Oct 15, 2026-6pm EDT Oct 22, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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