Current conditions at
Islip, Long Island Mac Arthur Airport (KISP)
Lat: 40.79°NLon: 73.1°WElev: 98ft.
Fair
41°F
5°C
| Humidity | 51% |
| Wind Speed | S 8 mph |
| Barometer | 30.60 in (1036.1 mb) |
| Dewpoint | 24°F (-4°C) |
| Visibility | 10.00 mi |
| Wind Chill | 36°F (2°C) |
| Last update | 8 Apr 5:56 pm EDT |
Extended Forecast for
Port Jefferson NY
Tonight
Low: 32 °F
Frost
Thursday
High: 52 °F
Areas Frost
then SunnyThursday Night
Low: 36 °F
Mostly Clear
Friday
High: 57 °F
Sunny
Friday Night
Low: 45 °F
Mostly Cloudy
then Slight
Chance
ShowersSaturday
High: 58 °F
Sunny
Saturday Night
Low: 40 °F
Mostly Clear
Sunday
High: 55 °F
Sunny
Sunday Night
Low: 45 °F
Mostly Cloudy
Detailed Forecast
Tonight
Widespread frost, mainly after 1am. Otherwise, clear, with a low around 32. South wind around 5 mph becoming calm in the evening.
Thursday
Areas of frost before 9am. Otherwise, sunny, with a high near 52. Calm wind becoming south 5 to 7 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 36. South wind around 5 mph becoming calm in the evening.
Friday
Sunny, with a high near 57. Calm wind becoming south 5 to 8 mph in the morning.
Friday Night
A 20 percent chance of showers after 2am. Mostly cloudy, with a low around 45. South wind 6 to 8 mph.
Saturday
Sunny, with a high near 58.
Saturday Night
Mostly clear, with a low around 40.
Sunday
Sunny, with a high near 55.
Sunday Night
Mostly cloudy, with a low around 45.
Monday
Mostly cloudy, with a high near 64.
Monday Night
Mostly cloudy, with a low around 54.
Tuesday
Mostly sunny, with a high near 71.
Tuesday Night
Mostly cloudy, with a low around 56.
Wednesday
Mostly sunny, with a high near 71.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Port Jefferson NY
40.93°N 73.06°W (Elev. 161 ft)
40.93°N 73.06°W (Elev. 161 ft)
5:30 pm EDT Apr 8, 2026
6pm EDT Apr 8, 2026-6pm EDT Apr 15, 2026
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