Great South Bay Weather Forecast
- 72
- 89
Chance Thunderstorms
- 70
- 79
Rain
- 69
- 76
Rain
- 68
- 76
Rain Showers Likely
- 71
- 79
Partly Sunny
- 74
- 81
Partly Sunny
- 73
- 82
Chance Rain Showers
Today 4 Jul Southwest Suffolk
Partly sunny. A chance of Showers and Thunderstorms this afternoon. Some Thunderstorms may produce gusty Winds this afternoon. Highs in the lower 90s. West Winds 10 to 15 Mph. Chance of rain 50 percent. Heat index Values up to 102.
Tonight 4 Jul Southwest Suffolk
Showers likely with a chance of Thunderstorms. Some Thunderstorms may produce gusty Winds and heavy rainfall this evening. Lows in the lower 70s. West Winds 5 to 10 Mph. Gusts up to 20 Mph this evening. Chance of rain 70 percent.
Great South Bay Temperature Statistics
July Temperature
Islip, Long Island Mac Arthur Airport (8.1 miles)
Lowest 1 July, 2026
69.7 °FAverage July
80.2 °FHighest 2 July, 2026
93.9 °F
Climate (2021–2026)
Islip, Long Island Mac Arthur Airport (8.1 miles)
Average Low 2021–2026
47.3 °FAverage 2021–2026
55.2 °FAverage High 2021–2026
63.1 °F