National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Overcast

73°F

23°C

Humidity 96%
Wind Speed SW 6 mph
Barometer 29.95 in (1013.9 mb)
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Last update 1 Aug 3:56 am EDT
Extended Forecast for

Head of the Harbor NY

  • Today

    Today: Partly sunny, with a high near 84. Calm wind becoming south 5 to 9 mph in the afternoon.

    High: 84 °F

    Partly Sunny

  • Tonight

    Tonight: Mostly cloudy, with a low around 70. South wind 6 to 8 mph.

    Low: 70 °F

    Mostly Cloudy

  • Sunday

    Sunday: Mostly cloudy, with a high near 83. South wind 6 to 11 mph.

    High: 83 °F

    Mostly Cloudy

  • Sunday Night

    Sunday Night: Showers and possibly a thunderstorm. Low around 71. Southeast wind around 8 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.

    Low: 71 °F

    Showers

  • Monday

    Monday: Showers and possibly a thunderstorm. High near 82. Southwest wind 10 to 13 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

    High: 82 °F

    Showers

  • Monday Night

    Monday Night: Showers likely and possibly a thunderstorm before 8pm, then a chance of showers and thunderstorms between 8pm and 2am, then a chance of showers after 2am. Mostly cloudy, with a low around 70. Chance of precipitation is 60%.

    Low: 70 °F

    Showers
    Likely then
    Chance
    T-storms

  • Tuesday

    Tuesday: A 30 percent chance of showers before 2pm. Partly sunny, with a high near 83.

    High: 83 °F

    Chance
    Showers

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 70.

    Low: 70 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 83.

    High: 83 °F

    Partly Sunny

Detailed Forecast

Today
Partly sunny, with a high near 84. Calm wind becoming south 5 to 9 mph in the afternoon.
Tonight
Mostly cloudy, with a low around 70. South wind 6 to 8 mph.
Sunday
Mostly cloudy, with a high near 83. South wind 6 to 11 mph.
Sunday Night
Showers and possibly a thunderstorm. Low around 71. Southeast wind around 8 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.
Monday
Showers and possibly a thunderstorm. High near 82. Southwest wind 10 to 13 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Monday Night
Showers likely and possibly a thunderstorm before 8pm, then a chance of showers and thunderstorms between 8pm and 2am, then a chance of showers after 2am. Mostly cloudy, with a low around 70. Chance of precipitation is 60%.
Tuesday
A 30 percent chance of showers before 2pm. Partly sunny, with a high near 83.
Tuesday Night
Mostly cloudy, with a low around 70.
Wednesday
Partly sunny, with a high near 83.
Wednesday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 71.
Thursday
A 30 percent chance of showers. Partly sunny, with a high near 85.
Thursday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 72.
Friday
A 40 percent chance of showers. Mostly sunny, with a high near 85.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Head of the Harbor NY
 40.88°N 73.16°W (Elev. 148 ft)
Last Update:
2:27 am EDT Aug 1, 2026
Forecast Valid:
4am EDT Aug 1, 2026-6pm EDT Aug 7, 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