Hazardous Weather Conditions
Current conditions at
Islip, Long Island Mac Arthur Airport (KISP)
Lat: 40.79°NLon: 73.1°WElev: 98ft.
Mostly Cloudy
76°F
24°C
| Humidity | 91% |
| Wind Speed | Calm |
| Barometer | 30.08 in (1018.5 mb) |
| Dewpoint | 73°F (23°C) |
| Visibility | 10.00 mi |
| Heat Index | 76°F (24°C) |
| Last update | 15 Jul 9:56 am EDT |
Extended Forecast for
Port Jefferson NY
Today
High: 85 °F
Chance
Showers then
Slight Chance
T-stormsTonight
Low: 73 °F
Patchy Fog
Wednesday
High: 88 °F
Patchy Fog
then Mostly
SunnyWednesday Night
Low: 75 °F
Chance
T-stormsThursday
High: 89 °F
Chance
Showers then
Chance
T-stormsThursday Night
Low: 77 °F
Chance
T-storms then
Partly CloudyFriday
High: 89 °F
Mostly Sunny
then Chance
T-stormsFriday Night
Low: 71 °F
Chance
T-storms then
Partly CloudySaturday
High: 84 °F
Sunny
Detailed Forecast
Today
A 30 percent chance of showers and thunderstorms, mainly before 11am. Mostly cloudy, then gradually becoming sunny, with a high near 85. South wind 5 to 7 mph.
Tonight
Patchy fog after 11pm. Otherwise, partly cloudy, with a low around 73. South wind 5 to 7 mph becoming calm after midnight.
Wednesday
Patchy fog before 9am. Otherwise, mostly sunny, with a high near 88. Heat index values as high as 97. South wind 3 to 8 mph.
Wednesday Night
A 50 percent chance of showers and thunderstorms, mainly after 8pm. Mostly cloudy, with a low around 75. South wind 6 to 9 mph.
Thursday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 89. Southwest wind 7 to 10 mph.
Thursday Night
A chance of thunderstorms before 8pm. Partly cloudy, with a low around 77. Chance of precipitation is 30%.
Friday
A 30 percent chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 89.
Friday Night
A 30 percent chance of showers and thunderstorms before 8pm. Mostly cloudy, with a low around 71.
Saturday
Sunny, with a high near 84.
Saturday Night
Mostly cloudy, with a low around 71.
Sunday
A 50 percent chance of showers. Partly sunny, with a high near 85.
Sunday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 71.
Monday
A 30 percent chance of showers. Mostly sunny, with a high near 85.
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 ft)
40.95°N 73.05°W (Elev. 151 ft)
6:03 am EDT Jul 15, 2025
10am EDT Jul 15, 2025-6pm EDT Jul 21, 2025
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