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

42°F

6°C

Humidity 76%
Wind Speed NE 3 mph
Barometer 30.27 in (1025.1 mb)
Dewpoint 35°F (2°C)
Visibility 10.00 mi
Last update 4 Mar 11:56 am EST
Extended Forecast for

2 Miles NNW Stony Brook NY

  • This Afternoon

    This Afternoon: Partly sunny, with a high near 44. Calm wind.

    High: 44 °F

    Partly Sunny

  • Tonight

    Tonight: A 20 percent chance of rain after 4am. Patchy fog after 10pm. Otherwise, mostly cloudy, with a low around 32. Calm wind.

    Low: 32 °F

    Patchy Fog
    then Slight
    Chance Rain
    and Patchy
    Fog

  • Thursday

    Thursday: Rain, mainly after 7am. Patchy fog before 10am. High near 41. Calm wind becoming northeast 5 to 7 mph in the afternoon. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.

    High: 41 °F

    Rain and
    Patchy Fog

  • Thursday Night

    Thursday Night: Rain. Low around 36. Northeast wind 11 to 14 mph. Chance of precipitation is 100%. New precipitation amounts between a half and three quarters of an inch possible.

    Low: 36 °F

    Rain

  • Friday

    Friday: A 30 percent chance of rain before 1pm. Mostly cloudy, with a high near 41. Northeast wind 7 to 13 mph.

    High: 41 °F

    Chance Rain

  • Friday Night

    Friday Night: Cloudy, with a low around 36.

    Low: 36 °F

    Cloudy

  • Saturday

    Saturday: Mostly cloudy, with a high near 51.

    High: 51 °F

    Mostly Cloudy

  • Saturday Night

    Saturday Night: Showers likely, mainly before 1am. Cloudy, with a low around 43. Chance of precipitation is 60%.

    Low: 43 °F

    Showers
    Likely

  • Sunday

    Sunday: Mostly sunny, with a high near 54.

    High: 54 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Partly sunny, with a high near 44. Calm wind.
Tonight
A 20 percent chance of rain after 4am. Patchy fog after 10pm. Otherwise, mostly cloudy, with a low around 32. Calm wind.
Thursday
Rain, mainly after 7am. Patchy fog before 10am. High near 41. Calm wind becoming northeast 5 to 7 mph in the afternoon. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Thursday Night
Rain. Low around 36. Northeast wind 11 to 14 mph. Chance of precipitation is 100%. New precipitation amounts between a half and three quarters of an inch possible.
Friday
A 30 percent chance of rain before 1pm. Mostly cloudy, with a high near 41. Northeast wind 7 to 13 mph.
Friday Night
Cloudy, with a low around 36.
Saturday
Mostly cloudy, with a high near 51.
Saturday Night
Showers likely, mainly before 1am. Cloudy, with a low around 43. Chance of precipitation is 60%.
Sunday
Mostly sunny, with a high near 54.
Sunday Night
Partly cloudy, with a low around 41.
Monday
Sunny, with a high near 57.
Monday Night
Mostly clear, with a low around 42.
Tuesday
Mostly sunny, with a high near 57.
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:
6:26 am EST Mar 4, 2026
Forecast Valid:
12pm EST Mar 4, 2026-6pm EDT Mar 10, 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