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Hazardous Weather Conditions
Current conditions at
Islip, Long Island Mac Arthur Airport (KISP)
Lat: 40.79°NLon: 73.1°WElev: 98ft.
Mostly Cloudy
83°F
28°C
| Humidity | 59% |
| Wind Speed | S 13 mph |
| Barometer | 30.03 in (1016.7 mb) |
| Dewpoint | 67°F (19°C) |
| Visibility | 10.00 mi |
| Heat Index | 86°F (30°C) |
| Last update | 12 Aug 2:56 pm EDT |
Extended Forecast for
Holtsville NY
Tonight
Low: 70 °F
Mostly Clear
then Patchy
FogWednesday
High: 84 °F
Patchy Fog
then Slight
Chance
T-stormsWednesday Night
Low: 72 °F
Chance
T-storms and
Patchy FogThursday
High: 86 °F
Chance
T-storms and
Patchy FogThursday Night
Low: 68 °F
Slight Chance
ShowersFriday
High: 85 °F
Sunny
Friday Night
Low: 67 °F
Mostly Clear
Saturday
High: 83 °F
Sunny
Saturday Night
Low: 67 °F
Mostly Clear
Detailed Forecast
Tonight
Patchy fog after 2am. Otherwise, partly cloudy, with a low around 70. Southwest wind 6 to 9 mph.
Wednesday
A 20 percent chance of showers and thunderstorms after 2pm. Patchy fog before 8am. Otherwise, mostly sunny, with a high near 84. Southwest wind 6 to 11 mph.
Wednesday Night
A 50 percent chance of showers and thunderstorms, mainly after 8pm. Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 72. South wind 3 to 8 mph.
Thursday
A 50 percent chance of showers and thunderstorms. Patchy fog before 8am. Otherwise, mostly cloudy, with a high near 86. Southwest wind 5 to 7 mph.
Thursday Night
A 20 percent chance of showers before 2am. Partly cloudy, with a low around 68. Calm wind becoming north around 5 mph after midnight.
Friday
Sunny, with a high near 85.
Friday Night
Mostly clear, with a low around 67.
Saturday
Sunny, with a high near 83.
Saturday Night
Mostly clear, with a low around 67.
Sunday
Sunny, with a high near 86.
Sunday Night
Partly cloudy, with a low around 70.
Monday
Mostly sunny, with a high near 85.
Monday Night
Mostly cloudy, with a low around 66.
Tuesday
Partly sunny, with a high near 81.
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)
1:55 pm EDT Aug 12, 2025
3pm EDT Aug 12, 2025-6pm EDT Aug 19, 2025
Additional Resources
Radar & Satellite Image
Hourly Weather Forecast
