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.

Overcast

36°F

2°C

Humidity 89%
Wind Speed NE 6 mph
Barometer 30.42 in (1030.1 mb)
Dewpoint 33°F (1°C)
Visibility 10.00 mi
Wind Chill31°F (-1°C)
Last update 6 Mar 9:56 pm EST
Extended Forecast for

Smithtown NY

  • Tonight

    Tonight: A chance of drizzle after 4am. Cloudy, with a low around 33. Calm wind.

    Low: 33 °F

    Cloudy then
    Chance
    Drizzle

  • Saturday

    Saturday: A chance of drizzle before 7am. Cloudy, with a high near 50. Calm wind becoming south 5 to 7 mph in the afternoon.

    High: 50 °F

    Chance
    Drizzle then
    Cloudy

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms, then showers likely after 1am. Patchy dense fog. Otherwise, cloudy, with a low around 44. Southwest wind 5 to 7 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 44 °F

    Showers
    Likely and
    Patchy Dense
    Fog

  • Sunday

    Sunday: A 30 percent chance of showers before 1pm. Cloudy, then gradually becoming mostly sunny, with a high near 58. West wind 7 to 9 mph.

    High: 58 °F

    Chance
    Showers

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 38. Light west wind.

    Low: 38 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 57.

    High: 57 °F

    Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 41.

    Low: 41 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 59.

    High: 59 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: A 30 percent chance of rain after 1am. Mostly cloudy, with a low around 41.

    Low: 41 °F

    Mostly Cloudy
    then Chance
    Rain

Detailed Forecast

Tonight
A chance of drizzle after 4am. Cloudy, with a low around 33. Calm wind.
Saturday
A chance of drizzle before 7am. Cloudy, with a high near 50. Calm wind becoming south 5 to 7 mph in the afternoon.
Saturday Night
A chance of showers and thunderstorms, then showers likely after 1am. Patchy dense fog. Otherwise, cloudy, with a low around 44. Southwest wind 5 to 7 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Sunday
A 30 percent chance of showers before 1pm. Cloudy, then gradually becoming mostly sunny, with a high near 58. West wind 7 to 9 mph.
Sunday Night
Mostly clear, with a low around 38. Light west wind.
Monday
Sunny, with a high near 57.
Monday Night
Partly cloudy, with a low around 41.
Tuesday
Mostly sunny, with a high near 59.
Tuesday Night
A 30 percent chance of rain after 1am. Mostly cloudy, with a low around 41.
Wednesday
A 50 percent chance of rain. Cloudy, with a high near 55.
Wednesday Night
Rain likely. Cloudy, with a low around 37. Chance of precipitation is 60%.
Thursday
A 40 percent chance of rain. Mostly cloudy, with a high near 47.
Thursday Night
Mostly cloudy, with a low around 30.
Friday
Mostly cloudy, with a high near 44.
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 73.19°W (Elev. 98 ft)
Last Update:
12:51 pm EST Mar 6, 2026
Forecast Valid:
10pm EST Mar 6, 2026-6pm EDT Mar 13, 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