Current conditions at
Islip, Long Island Mac Arthur Airport (KISP)
Lat: 40.79°NLon: 73.1°WElev: 98ft.
Mostly Cloudy
48°F
9°C
| Humidity | 66% |
| Wind Speed | NW 14 mph |
| Barometer | 29.88 in (1012.0 mb) |
| Dewpoint | 37°F (3°C) |
| Visibility | 10.00 mi |
| Wind Chill | 42°F (6°C) |
| Last update | 5 Apr 11:56 pm EDT |
Extended Forecast for
Port Jefferson NY
Overnight
Low: 39 °F
Clear
Monday
High: 53 °F
Sunny
Monday Night
Low: 38 °F
Slight Chance
ShowersTuesday
High: 50 °F
Slight Chance
ShowersTuesday Night
Low: 31 °F
Mostly Clear
Wednesday
High: 47 °F
Sunny
Wednesday Night
Low: 34 °F
Mostly Clear
Thursday
High: 51 °F
Mostly Sunny
Thursday Night
Low: 41 °F
Partly Cloudy
Detailed Forecast
Overnight
Mostly cloudy early, then becoming clear, with a low around 39. West wind around 10 mph.
Monday
Sunny, with a high near 53. West wind around 14 mph.
Monday Night
A 20 percent chance of showers. Partly cloudy, with a low around 38. West wind around 6 mph.
Tuesday
A 20 percent chance of showers before 2pm. Mostly sunny, with a high near 50. West wind 7 to 13 mph.
Tuesday Night
Mostly clear, with a low around 31. Northwest wind 8 to 10 mph.
Wednesday
Sunny, with a high near 47.
Wednesday Night
Mostly clear, with a low around 34.
Thursday
Mostly sunny, with a high near 51.
Thursday Night
Partly cloudy, with a low around 41.
Friday
Mostly sunny, with a high near 62.
Friday Night
Partly cloudy, with a low around 47.
Saturday
Mostly sunny, with a high near 66.
Saturday Night
Partly cloudy, with a low around 45.
Sunday
Mostly sunny, with a high near 60.
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)
6:30 pm EDT Apr 5, 2026
12am EDT Apr 6, 2026-6pm EDT Apr 12, 2026
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