Port Jefferson Weather Forecast
- 73
- 82
Slight Chance Thunderstorms
- 74
- 84
Chance Thunderstorms
- 76
- 85
Rain Showers Likely
- 69
- 85
Chance Thunderstorms
- 70
- 80
Partly Sunny
- 71
- 81
Chance Rain Showers
- 69
- 81
Chance Rain Showers
Today 15 Jul Northwest Suffolk
Sunny with a slight chance of Showers and Thunderstorms. Near steady temperature in the mid 80s. South Winds around 5 Mph. Chance of rain 20 percent. Heat index Values in the mid 90s.
Tonight 15 Jul Northwest Suffolk
Mostly clear this Evening, then becoming partly cloudy. Patchy fog after midnight. Lows in the lower 70s. South Winds around 5 Mph.
Port Jefferson Temperature Statistics
July Temperature
Islip, Long Island Mac Arthur Airport (10.6 miles)
Lowest 5 July, 2025
64.7 °FAverage July
77.3 °FHighest 8 July, 2025
92.6 °F
Climate (2020–Present)
Islip, Long Island Mac Arthur Airport (10.6 miles)
Average Low 2020–2025
47.5 °FAverage 2020–2025
55.2 °FAverage High 2020–2025
63 °F