The city is characterized by a Mediterranean climate, with hot, dry summers, and mild, wet winters. Snow flurries usually occur once or twice a winter, although the city experiences heavy snowfall every three to four years, on average, with short-lived accumulation. January is the coldest month of the year, with an average temperature of 9.1 °C (48.4 °F); July and August are the hottest months, with an average temperature of 24.2 °C (75.6 °F), and the summer months are usually rainless. The average annual precipitation is around 550 mm (22 in), with rain occurring almost entirely between October and May. Jerusalem has nearly 3,400 annual sunshine hours.
Most of the air pollution in Jerusalem comes from vehicular traffic. Many main streets in Jerusalem were not built to accommodate such a large volume of traffic, leading to traffic congestion and more carbon monoxide released into the air. Industrial pollution inside the city is sparse, but emissions from factories on the Israeli Mediterranean coast can travel eastward and settle over the
