The Dead Sea region has a hot desert climate moderated slightly by its extreme below-sea-level position. The dense, oxygen-rich air and the therapeutic mud and mineral water attract visitors year-round, but the optimal seasons depend on what you plan to do.
October to April is the best window for most activities. Day temperatures are comfortable (18–25°C), nights are cool, and the air feels crisp and clear. The Dead Sea itself remains warm enough for swimming — water temperature varies little year-round, staying around 30–33°C. Hiking in Wadi Mujib and visiting outdoor sites like Machaerus and Mount Nebo is most pleasant in this period.
May to September is very hot. The temperature on the shore regularly exceeds 40°C and occasionally reaches 45°C. Swimming in the sea itself is pleasant — the water is warm and the flotation experience unchanged — but the beach time before and after involves significant heat exposure. The Wadi Mujib canyon trail runs in summer but can be hazardous in extreme heat; the RSCN sometimes closes it during heat waves.
Wadi Mujib seasonality: The canyon trail is only open March to October, avoiding the flash flood risk season. Exact opening dates vary; check with the RSCN before planning.
The Dead Sea level drops roughly one metre per year due to water diversion from the Jordan River. The shoreline has receded significantly since the mid-20th century. This is a place to visit sooner rather than later — what remains is spectacular, but it is not what existed a generation ago.