A significant and unusually long heat wave is beginning, with temperatures potentially reaching nearly 50 degrees next week. Today, temperatures will rise in the mountains and inland areas, becoming hotter than usual to scorching. The coastal plain will be humid. Most areas of the country will experience heavy to extreme heat stress. Tomorrow will continue to be hotter than usual to scorching in the mountains and inland, and humid along the coast. Heat stress will intensify further with heavy to extreme heat stress across all regions of the country. Expected temperatures today and tonight: Jerusalem 20-36, Tel Aviv 26-31, Haifa 25-30, Safed 20-38, Katzrin 23-40, Tiberias 27-41, Nazareth 23-32, Afula 24-37, Beit Shean 25-41, Lod 25-33, Ashdod 26-30, Beer Sheva 23-34, Ein Gedi 26-40, Mitzpe Ramon 19-34, Eilat 28-42.