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.

Mostly Cloudy

52°F

11°C

Humidity 53%
Wind Speed SW 10 mph
Barometer 29.76 in (1007.6 mb)
Dewpoint 35°F (2°C)
Visibility 10.00 mi
Wind Chill49°F (9°C)
Last update 8 Nov 10:56 pm EST
Extended Forecast for

Smithtown NY

  • Tonight

    Tonight: Mostly clear, with a steady temperature around 45. West wind around 9 mph.

    Low: 45 °F

    Mostly Clear

  • Monday

    Monday: Mostly cloudy, then gradually becoming sunny, with a high near 58. Northwest wind 9 to 15 mph, with gusts as high as 26 mph.

    High: 58 °F

    Decreasing
    Clouds

  • Monday Night

    Monday Night: Mostly clear, with a low around 39. Northwest wind 7 to 10 mph, with gusts as high as 20 mph.

    Low: 39 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 60. West wind 7 to 10 mph.

    High: 60 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Clear, with a low around 43. West wind around 7 mph.

    Low: 43 °F

    Clear

  • Veterans Day

    Veterans Day: Sunny, with a high near 61.

    High: 61 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 41.

    Low: 41 °F

    Mostly Cloudy

  • Thursday

    Thursday: A 40 percent chance of rain after 1pm. Mostly cloudy, with a high near 57.

    High: 57 °F

    Mostly Cloudy
    then Chance
    Rain

  • Thursday Night

    Thursday Night: Rain. Low around 38. Chance of precipitation is 80%.

    Low: 38 °F

    Rain

Detailed Forecast

Tonight
Mostly clear, with a steady temperature around 45. West wind around 9 mph.
Monday
Mostly cloudy, then gradually becoming sunny, with a high near 58. Northwest wind 9 to 15 mph, with gusts as high as 26 mph.
Monday Night
Mostly clear, with a low around 39. Northwest wind 7 to 10 mph, with gusts as high as 20 mph.
Tuesday
Mostly sunny, with a high near 60. West wind 7 to 10 mph.
Tuesday Night
Clear, with a low around 43. West wind around 7 mph.
Veterans Day
Sunny, with a high near 61.
Wednesday Night
Mostly cloudy, with a low around 41.
Thursday
A 40 percent chance of rain after 1pm. Mostly cloudy, with a high near 57.
Thursday Night
Rain. Low around 38. Chance of precipitation is 80%.
Friday
Rain. High near 49. Chance of precipitation is 80%.
Friday Night
A 40 percent chance of rain. Mostly cloudy, with a low around 34.
Saturday
A 30 percent chance of rain. Partly sunny, with a high near 47.
Saturday Night
Partly cloudy, with a low around 33.
Sunday
Mostly sunny, with a high near 48.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Smithtown NY
 40.84°N 73.22°W (Elev. 49 ft)
Last Update:
1:44 pm EST Nov 8, 2026
Forecast Valid:
11pm EST Nov 8, 2026-6pm EST Nov 15, 2026
 
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