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.

Partly Cloudy

46°F

8°C

Humidity 79%
Wind Speed SE 5 mph
Barometer 29.98 in (1015.2 mb)
Dewpoint 40°F (4°C)
Visibility 10.00 mi
Wind Chill44°F (7°C)
Last update 11 Mar 4:56 am EDT
Extended Forecast for

Islandia NY

  • Today

    Today: A 30 percent chance of showers after 2pm. Increasing clouds, with a high near 66. Light south wind increasing to 6 to 11 mph in the morning.

    High: 66 °F

    Partly Sunny
    then Chance
    Showers

  • Tonight

    Tonight: A 40 percent chance of showers and thunderstorms, mainly after 5am. Areas of fog before 3am. Otherwise, mostly cloudy, with a low around 41. South wind around 10 mph, with gusts as high as 24 mph.

    Low: 41 °F

    Chance
    Showers and
    Areas Fog

  • Thursday

    Thursday: Rain showers likely before 2pm, then a chance of rain and snow showers. Cloudy, with a temperature rising to near 53 by 10am, then falling to around 41 during the remainder of the day. Northwest wind 10 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 60%. Little or no snow accumulation expected.

    High: 53 °F⇓

    Showers
    Likely then
    Rain/Snow
    Likely

  • Thursday Night

    Thursday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 31. Northwest wind 5 to 7 mph.

    Low: 31 °F

    Decreasing
    Clouds

  • Friday

    Friday: Increasing clouds, with a high near 46. Light and variable wind becoming south 9 to 14 mph in the morning. Winds could gust as high as 25 mph.

    High: 46 °F

    Increasing
    Clouds

  • Friday Night

    Friday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 36.

    Low: 36 °F

    Decreasing
    Clouds

  • Saturday

    Saturday: Sunny, with a high near 48.

    High: 48 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 31.

    Low: 31 °F

    Mostly Cloudy

  • Sunday

    Sunday: Cloudy, with a high near 49.

    High: 49 °F

    Cloudy

Detailed Forecast

Today
A 30 percent chance of showers after 2pm. Increasing clouds, with a high near 66. Light south wind increasing to 6 to 11 mph in the morning.
Tonight
A 40 percent chance of showers and thunderstorms, mainly after 5am. Areas of fog before 3am. Otherwise, mostly cloudy, with a low around 41. South wind around 10 mph, with gusts as high as 24 mph.
Thursday
Rain showers likely before 2pm, then a chance of rain and snow showers. Cloudy, with a temperature rising to near 53 by 10am, then falling to around 41 during the remainder of the day. Northwest wind 10 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 60%. Little or no snow accumulation expected.
Thursday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 31. Northwest wind 5 to 7 mph.
Friday
Increasing clouds, with a high near 46. Light and variable wind becoming south 9 to 14 mph in the morning. Winds could gust as high as 25 mph.
Friday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 36.
Saturday
Sunny, with a high near 48.
Saturday Night
Mostly cloudy, with a low around 31.
Sunday
Cloudy, with a high near 49.
Sunday Night
Rain, mainly after 2am. Low around 40. Chance of precipitation is 80%.
Monday
Rain. High near 54. Chance of precipitation is 90%.
Monday Night
Rain likely. Mostly cloudy, with a low around 28. Chance of precipitation is 60%.
Tuesday
Mostly sunny, with a high near 40.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Islandia NY
 40.81°N 73.17°W (Elev. 161 ft)
Last Update:
3:05 am EDT Mar 11, 2026
Forecast Valid:
5am EDT Mar 11, 2026-6pm EDT Mar 17, 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