Hazardous Weather Conditions
Current conditions at
Islip, Long Island Mac Arthur Airport (KISP)
Lat: 40.79°NLon: 73.1°WElev: 98ft.
A Few Clouds
86°F
30°C
| Humidity | 67% |
| Wind Speed | N 8 mph |
| Barometer | 30.09 in (1018.9 mb) |
| Dewpoint | 74°F (23°C) |
| Visibility | 10.00 mi |
| Heat Index | 94°F (34°C) |
| Last update | 24 Jun 7:56 am EDT |
Extended Forecast for
Holtsville NY
Extreme Heat Warning June 24, 08:56am until June 24, 08:00pm
NOW until 8:00pm Tue
Extreme Heat Warning
Today
High: 99 °F
Sunny
Tonight
Low: 76 °F
Mostly Clear
Wednesday
High: 93 °F
Sunny then
Chance
T-stormsWednesday Night
Low: 71 °F
Chance
T-stormsThursday
High: 74 °F⇓
Chance
ShowersThursday Night
Low: 62 °F
Chance
ShowersFriday
High: 70 °F
Mostly Cloudy
Friday Night
Low: 63 °F
Mostly Cloudy
then Chance
Showers
Detailed Forecast
Today
Sunny, with a high near 99. Heat index values as high as 104. Calm wind becoming southwest 5 to 8 mph in the morning.
Tonight
Mostly clear, with a low around 76. Southwest wind around 6 mph becoming calm in the evening.
Wednesday
A 30 percent chance of showers and thunderstorms after 2pm. Sunny, with a high near 93. Heat index values as high as 98. Light and variable wind becoming northwest 5 to 7 mph in the morning.
Wednesday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 71. Calm wind becoming northeast around 5 mph after midnight.
Thursday
A chance of showers and thunderstorms. Mostly cloudy, with a temperature falling to around 70 by 5pm. East wind 6 to 10 mph. Chance of precipitation is 40%.
Thursday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 62.
Friday
Mostly cloudy, with a high near 70.
Friday Night
A 30 percent chance of showers after 2am. Mostly cloudy, with a low around 63.
Saturday
A chance of showers before 8am, then a chance of showers after 2pm. Mostly cloudy, with a high near 77. Chance of precipitation is 30%.
Saturday Night
A 40 percent chance of showers. Mostly cloudy, with a low around 67.
Sunday
Partly sunny, with a high near 81.
Sunday Night
Mostly cloudy, with a low around 68.
Monday
A 30 percent chance of showers. Partly sunny, with a high near 85.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Holtsville NY
40.82°N 73.05°W (Elev. 112 ft)
40.82°N 73.05°W (Elev. 112 ft)
6:48 am EDT Jun 24, 2025
8am EDT Jun 24, 2025-6pm EDT Jun 30, 2025
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