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.

Fog/Mist

47°F

8°C

Humidity 90%
Wind Speed NE 14 G 24 mph
Barometer 29.43 in (996.6 mb)
Dewpoint 44°F (7°C)
Visibility 6.00 mi
Wind Chill41°F (5°C)
Last update 13 Nov 3:56 am EST
Extended Forecast for

Smithtown NY

  • Overnight

    Overnight: Rain. Low around 40. Northeast wind around 14 mph, with gusts as high as 26 mph. Chance of precipitation is 80%.

    Low: 40 °F

    Rain

  • Friday

    Friday: Rain, mainly before 4pm. High near 47. North wind 11 to 16 mph, with gusts as high as 28 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 47 °F

    Rain

  • Friday Night

    Friday Night: A 30 percent chance of rain before 10pm. Mostly cloudy, with a low around 36. North wind around 8 mph.

    Low: 36 °F

    Chance Rain
    then Mostly
    Cloudy

  • Saturday

    Saturday: Mostly cloudy, then gradually becoming sunny, with a high near 48. Northwest wind 8 to 13 mph.

    High: 48 °F

    Decreasing
    Clouds

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 34. Northwest wind around 9 mph.

    Low: 34 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 50.

    High: 50 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 34.

    Low: 34 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 51.

    High: 51 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 34.

    Low: 34 °F

    Mostly Clear

Detailed Forecast

Overnight
Rain. Low around 40. Northeast wind around 14 mph, with gusts as high as 26 mph. Chance of precipitation is 80%.
Friday
Rain, mainly before 4pm. High near 47. North wind 11 to 16 mph, with gusts as high as 28 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.
Friday Night
A 30 percent chance of rain before 10pm. Mostly cloudy, with a low around 36. North wind around 8 mph.
Saturday
Mostly cloudy, then gradually becoming sunny, with a high near 48. Northwest wind 8 to 13 mph.
Saturday Night
Partly cloudy, with a low around 34. Northwest wind around 9 mph.
Sunday
Mostly sunny, with a high near 50.
Sunday Night
Mostly clear, with a low around 34.
Monday
Sunny, with a high near 51.
Monday Night
Mostly clear, with a low around 34.
Tuesday
Sunny, with a high near 54.
Tuesday Night
Mostly clear, with a low around 36.
Wednesday
Sunny, with a high near 58.
Wednesday Night
Mostly clear, with a low around 37.
Thursday
Sunny, with a high near 59.
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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:
1:45 am EST Nov 13, 2026
Forecast Valid:
4am EST Nov 13, 2026-6pm EST Nov 19, 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