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.

Fair

44°F

7°C

Humidity 79%
Wind Speed SW 8 mph
Barometer 30.36 in (1028.1 mb)
Dewpoint 38°F (3°C)
Visibility 10.00 mi
Wind Chill39°F (4°C)
Last update 30 Mar 1:56 am EDT
Extended Forecast for

2 Miles NNW Stony Brook NY

  • Overnight

    Overnight: Mostly cloudy, with a low around 42. South wind around 13 mph.

    Low: 42 °F

    Mostly Cloudy

  • Monday

    Monday: A 20 percent chance of showers after 2pm. Partly sunny, with a high near 61. Southwest wind 14 to 16 mph, with gusts as high as 29 mph.

    High: 61 °F

    Partly Sunny
    then Slight
    Chance
    Showers

  • Monday Night

    Monday Night: Showers likely, mainly after 5am. Mostly cloudy, with a low around 49. Southwest wind 10 to 14 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

    Low: 49 °F

    Chance
    Showers then
    Showers
    Likely

  • Tuesday

    Tuesday: Showers likely, mainly before 8am. Mostly cloudy, with a high near 66. Southwest wind 11 to 14 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 66 °F

    Showers
    Likely then
    Chance
    Showers

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 53. South wind 15 to 17 mph.

    Low: 53 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Showers likely after 2pm. Partly sunny, with a high near 68. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

    High: 68 °F

    Partly Sunny
    then Showers
    Likely

  • Wednesday Night

    Wednesday Night: Showers likely before 8pm, then showers likely and possibly a thunderstorm between 8pm and 2am, then a chance of showers after 2am. Mostly cloudy, with a low around 45. Chance of precipitation is 60%.

    Low: 45 °F

    Showers
    Likely

  • Thursday

    Thursday: A 40 percent chance of showers before 2pm. Mostly cloudy, with a high near 52.

    High: 52 °F

    Chance
    Showers

  • Thursday Night

    Thursday Night: A 40 percent chance of rain. Cloudy, with a low around 43.

    Low: 43 °F

    Chance Rain

Detailed Forecast

Overnight
Mostly cloudy, with a low around 42. South wind around 13 mph.
Monday
A 20 percent chance of showers after 2pm. Partly sunny, with a high near 61. Southwest wind 14 to 16 mph, with gusts as high as 29 mph.
Monday Night
Showers likely, mainly after 5am. Mostly cloudy, with a low around 49. Southwest wind 10 to 14 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Tuesday
Showers likely, mainly before 8am. Mostly cloudy, with a high near 66. Southwest wind 11 to 14 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.
Tuesday Night
Mostly cloudy, with a low around 53. South wind 15 to 17 mph.
Wednesday
Showers likely after 2pm. Partly sunny, with a high near 68. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Wednesday Night
Showers likely before 8pm, then showers likely and possibly a thunderstorm between 8pm and 2am, then a chance of showers after 2am. Mostly cloudy, with a low around 45. Chance of precipitation is 60%.
Thursday
A 40 percent chance of showers before 2pm. Mostly cloudy, with a high near 52.
Thursday Night
A 40 percent chance of rain. Cloudy, with a low around 43.
Friday
A 30 percent chance of rain. Cloudy, with a high near 60.
Friday Night
A 40 percent chance of rain. Mostly cloudy, with a low around 49.
Saturday
A 30 percent chance of rain. Mostly cloudy, with a high near 61.
Saturday Night
A 40 percent chance of rain. Cloudy, with a low around 45.
Sunday
A 50 percent chance of rain. Cloudy, 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:
2 Miles NNW Stony Brook NY
 40.92°N 73.15°W (Elev. 36 ft)
Last Update:
2:28 am EDT Mar 30, 2026
Forecast Valid:
2am EDT Mar 30, 2026-6pm EDT Apr 5, 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