The city is characterized by a hot-summer 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 537 mm (21 in), with rain occurring almost entirely between October and May. Snowfall is rare, and large snowfalls are even more rare. Jerusalem received over 30 centimetres (12 in) of snow on 13 December 2013, which nearly paralyzed the city. A day in Jerusalem has on average, 9.3 sunshine hours. With summers averaging similar temperatures as the coastline, the maritime influence from the Mediterranean Sea is strong, in particular given that Jerusalem is located on a similar latitude as scorching hot deserts not far to its east.
The highest recorded temperature in Jerusalem was 44.4 °C (111.9 °F) on 28 and 30 August 1881, and the lowest temperature recorded was −6.7 °C (19.9 °F) on 25 January 1907.
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 city.