winter period, but heavy snow accumulation is rare and the snowcover lasts only for a few hours or a few days if heavy. In summer, temperatures are usually above and sometimes above . In spring and autumn, the temperatures range from . In winter, the day temperatures are roughly in the range from , but at nights they often fall below and sometimes below . Typically, temperatures throughout one year range from −13 °C to 39 °C. Occurrences of precipitation are evenly distributed throughout the year, being heaviest from October to December, and from April to June. Environment The City of Skopje encompasses various natural environments and its fauna and flora are rich. However, it is threatened by the intensification of agriculture and the urban extension. The largest protected area within the city limits is Mount Vodno, which is a popular leisure destination. A cable car connects its peak to the downtown, and many pedestrian paths run through its woods. Other large natural spots include the Matka Canyon. The city itself comprises several parks and gardens amounting to 4,361 hectares. Among these are the City Park (Gradski Park), built by the Ottoman Turks at the beginning of the 20th century; Žena Borec Park, in front of the Parliament; the university arboretum; and Gazi Baba forest. Many streets and boulevards are planted with trees. Skopje experiences many environmental issues which are often overshadowed by the economic poverty of the country. However, alignment of North Macedonian law on European law has brought progress in some fields, such as water and waste treatment, and industrial emissions. Skopje remains one of the most polluted cities in the world, topping the ranks in December 2017. Steel processing, which a crucial activity for the local economy, is responsible for soil pollution with heavy metals such as lead, zinc and cadmium, and air pollution with nitrogen oxide and carbon monoxide. Vehicle traffic and district heating plants are also responsible for air pollution. The highest pollution levels usually occur in autumn and winter. Water treatment plants are being built, but much polluted water is still discharged untreated into the Vardar. Waste is disposed of in the open-air municipal landfill site, north of the city. Every day, it receives 1,500 m3 of domestic waste and 400 m3 of industrial waste. Health levels are better in Skopje than in the rest of North Macedonia, and no link has been found