The land around the Dead Sea is a spectacular dessert, with sunny skies almost year-round. In the summer the temperature rises to 40ºc and can sometimes reach 48ºc. The winter is still relatively warm. The temperature scarcely drops beneath 10ºc and the average in January is around 13ºc. The humidity of the air hardly exceeds 40% and it drops in the summer to an average of 23%.
The Dead Sea desert is a “rain-shadow”. This is a unique phenomenon, of desert areas evolving next to rainy areas. The clouds form over the Mediterranean Sea and are blown Westbound with the breeze. While climbing up the Judean Mountain range (average 800m) they get cooler and the barometric pressure drops; the outcome is rain. As the breeze carries the clouds onward they glide down towards the Dead Sea. During the roughly 1km drop the temperature and pressure increase, the clouds’ capacity of holding water is maximal, and during their passage above the lowest point on Earth, no rain is shed. The next phase of this journey is the climb up the Jordanian mountain range, towering to over 1600m. This area gets even greater amounts of rain than the Judean Mountains. Thus, the Dead Sea, in the heart of the Great Rift enjoys less than 50mm of rain per year, while its neighboring mountains get over 800mm on average.
Above 90% of the world, desert land ranges between latitudes 20-30, and are caused by global meteorological factors. The Dead Sea is located between 31º-32º, and can ‘enjoy’ the relatively prodigious rain water. On the Eastern side, one can enjoy massive rivers that create spectacular canyons sloping down to the Dead Sea shores. On the Western side, the water flows underground and ensues as a belt of spring to create a lively oasis in the heart of the barren land.
The Great Rift Valley is a 6,000km long fault that stretches from Turkey to Mozambique. In the autumn and spring, the winds blow along the valley. From the Red Sea, they bring the only clouds that shed the annual amount of rain. In those very few days, the barren dry valleys get filled with rain water, and the outcome is massive flash floods that last only a few hours but can flood vast plains within minutes. They dig notable channels in the soft rock that forms the shores of the Dead Sea. Such powerful flash-floods were strong enough to break down a wide modern concrete bridge near Ein Gedi in 2003.