Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Overcast

65°F

18°C

Humidity 78%
Wind Speed NE 6 mph
Barometer 30.18 in (1021.8 mb)
Dewpoint 58°F (14°C)
Visibility 10.00 mi
Last update 27 Jun 3:56 am EDT
Extended Forecast for

Holtsville NY

  • Today

    Today: Partly sunny, with a high near 70. East wind 9 to 14 mph.

    High: 70 °F

    Partly Sunny

  • Tonight

    Tonight: A chance of showers between 11pm and 2am, then a chance of showers and thunderstorms after 2am.  Patchy fog after 2am.  Otherwise, mostly cloudy, with a low around 65. Southeast wind 8 to 10 mph.  Chance of precipitation is 50%.

    Low: 65 °F

    Chance
    Showers and
    Patchy Fog

  • Saturday

    Saturday: A 30 percent chance of showers and thunderstorms before 11am.  Patchy fog before 11am.  Otherwise, cloudy, then gradually becoming mostly sunny, with a high near 82. South wind 7 to 9 mph.

    High: 82 °F

    Chance
    Showers and
    Patchy Fog
    then Partly
    Sunny

  • Saturday Night

    Saturday Night: A 50 percent chance of showers and thunderstorms, mainly before 2am.  Mostly cloudy, with a low around 70. South wind 7 to 9 mph.

    Low: 70 °F

    Chance
    T-storms

  • Sunday

    Sunday: Mostly sunny, with a high near 87. West wind 3 to 6 mph.

    High: 87 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 66.

    Low: 66 °F

    Mostly Clear

  • Monday

    Monday: Mostly sunny, with a high near 86.

    High: 86 °F

    Mostly Sunny

  • Monday Night

    Monday Night: A chance of showers and thunderstorms.  Mostly cloudy, with a low around 71. Chance of precipitation is 40%.

    Low: 71 °F

    Chance
    T-storms

  • Tuesday

    Tuesday: A 50 percent chance of showers.  Partly sunny, with a high near 85.

    High: 85 °F

    Chance
    Showers

Detailed Forecast

Today
Partly sunny, with a high near 70. East wind 9 to 14 mph.
Tonight
A chance of showers between 11pm and 2am, then a chance of showers and thunderstorms after 2am. Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 65. Southeast wind 8 to 10 mph. Chance of precipitation is 50%.
Saturday
A 30 percent chance of showers and thunderstorms before 11am. Patchy fog before 11am. Otherwise, cloudy, then gradually becoming mostly sunny, with a high near 82. South wind 7 to 9 mph.
Saturday Night
A 50 percent chance of showers and thunderstorms, mainly before 2am. Mostly cloudy, with a low around 70. South wind 7 to 9 mph.
Sunday
Mostly sunny, with a high near 87. West wind 3 to 6 mph.
Sunday Night
Mostly clear, with a low around 66.
Monday
Mostly sunny, with a high near 86.
Monday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 71. Chance of precipitation is 40%.
Tuesday
A 50 percent chance of showers. Partly sunny, with a high near 85.
Tuesday Night
Mostly cloudy, with a low around 71.
Wednesday
Mostly sunny, with a high near 88.
Wednesday Night
Partly cloudy, with a low around 69.
Thursday
Mostly sunny, with a high near 87.
Basemap Options
Click map to change the forecast location
Loading map...

ABOUT THIS FORECAST

 
Point Forecast:
Holtsville NY
 40.82°N 73.05°W (Elev. 112 ft)
3:15 am EDT Jun 27, 2025
4am EDT Jun 27, 2025-6pm EDT Jul 3, 2025
 
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