Current conditions at
Islip, Long Island Mac Arthur Airport (KISP)
Lat: 40.79°NLon: 73.1°WElev: 98ft.
Mostly Cloudy
25°C
77°F
| Humidity | 88% |
| Wind Speed | S 9 km/h |
| Barometer | 1013.7 mb (29.94 in) |
| Dewpoint | 23°C (73°F) |
| Visibility | 16 km |
| Heat Index | 26°C (78°F) |
| Last update | 30 Jun 9:56 pm EDT |
Extended Forecast for
Port Jefferson NY
Tonight
Low: 22 °C
Slight Chance
T-storms then
Showers
Likely and
Patchy FogTuesday
High: 30 °C
Chance
Showers and
Patchy Fog
then T-storms
LikelyTuesday Night
Low: 22 °C
T-storms
LikelyWednesday
High: 29 °C
Decreasing
CloudsWednesday Night
Low: 21 °C
Partly Cloudy
Thursday
High: 30 °C
Sunny
Thursday Night
Low: 19 °C
Mostly Clear
Independence Day
High: 29 °C
Sunny
Friday Night
Low: 19 °C
Mostly Clear
Detailed Forecast
Tonight
A chance of showers and thunderstorms before 2am, then showers likely and possibly a thunderstorm between 2am and 5am, then a chance of showers and thunderstorms after 5am. Patchy fog after 2am. Otherwise, cloudy, with a low around 22. South wind around 10 km/h. Chance of precipitation is 60%. New rainfall amounts between 5 and 7.5 mm possible.
Tuesday
A chance of showers, then showers and thunderstorms likely after 2pm. Patchy fog before 8am. Otherwise, mostly cloudy, with a high near 30. Southwest wind 13 to 21 km/h. Chance of precipitation is 60%. New rainfall amounts between 5 and 7.5 mm possible.
Tuesday Night
Showers and thunderstorms likely before 2am, then a chance of showers. Cloudy, with a low around 22. Southwest wind 10 to 14 km/h. Chance of precipitation is 60%. New rainfall amounts between 7.5 mm and 1 cm possible.
Wednesday
Cloudy, then gradually becoming mostly sunny, with a high near 29. West wind around 10 km/h.
Wednesday Night
Partly cloudy, with a low around 21. Southwest wind 5 to 11 km/h becoming west after midnight.
Thursday
Sunny, with a high near 30.
Thursday Night
Mostly clear, with a low around 19.
Independence Day
Sunny, with a high near 29.
Friday Night
Mostly clear, with a low around 19.
Saturday
Mostly sunny, with a high near 29.
Saturday Night
Mostly cloudy, with a low around 21.
Sunday
Partly sunny, with a high near 31.
Sunday Night
Mostly cloudy, with a low around 23.
Monday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 31.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Port Jefferson NY
40.95°N 73.05°W (Elev. 151 m)
40.95°N 73.05°W (Elev. 151 m)
10:25 pm EDT Jun 30, 2025
10pm EDT Jun 30, 2025-6pm EDT Jul 7, 2025
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