Jinan Climate
The highest temperature here is 42.5℃ (July 24, 1955), and the lowest is minus 19.7℃(January 17, 1953). The highest monthly average here is 27.2 ℃ in July and the lowest one is minus 3.2 ℃ in January.
Due to the mountains to the south of the city, temperature inversions are common, occurring on about 200 days per year. The high precipitation for northern Chinese standards, in tandem with the topography (mountains surrounding the city on three sides), leads to particularly oppressive summer weather and the city being named as a candidate for the fourth "furnace", etc.
In winter, Mongolian high pressure system forms in northern Asian continent, and Jinan is controlled by the polar continental air, so it is often affected by cold air invaded from the north, appearing with sunny but cold weather, little rain and snow, and northerly winds.
In summer, affected by tropical and subtropical maritime air, warm moist air flows come from the sea, so hot days, abundant rains, sufficient sunlight, and southerly winds arrive.
Spring and autumn are respectively transition seasons to summer and winter, coming with variable wind directions.
In a whole year, Jinan is under different atmospheric circulation control in different seasons, so that it has four distinctive seasons of warm spring, hot summer, cool autumn and cold winter. Winter here could last 136 to 157 days, and generally begins in early November and ends late March. Its summer spans late May to early September, 105 days to 120 days. Spring and autumn keep quite short time, less than two months. Besides, because of mountains around its three sides, which impact the spread of cold water vapor and reflowing hot air, summer precipitation here is more than other regular northern cities.