What is the temperature difference between Changchun and Tianjin in winter?

Changchun area belongs to continental monsoon climate zone, and it is in the transition zone from humid area to semi-arid area in the national dry-wet climate division. The temperature rises from east to west, and the precipitation decreases from east to west. Spring is short, dry and windy; In summer, the western Pacific subtropical high often meets the cold air moving southeast of Lake Baikal, which is warm and rainy. In autumn, the sky is crisp and the temperature difference between day and night is large; The winter is long, and the climate is cold and dry under the control of strong Mongolian high pressure. Four distinct seasons, rain and heat in the same season, moderate humidity. The annual average temperature is 4.9℃, the highest temperature is 39.5℃, the lowest temperature is -39.8℃, the sunshine time is 2688 hours, and the average frost-free period is 140- 150 days. Southeast winds prevail in summer, and there is moisture supplemented by Bohai Sea. The annual average precipitation is 522 ~ 6 15mm, and the summer precipitation accounts for more than 60% of the annual precipitation. The average temperature in the hottest month (July) is 23℃. Autumn can form sunny and warm weather for several days, with large temperature difference and lower wind speed than spring. Tianjin is located on the east coast of Eurasia in mid-latitude, and it is dominated by monsoon circulation. It is an area where East Asian monsoon prevails and belongs to temperate monsoon climate. The main climatic characteristics are: four distinct seasons, windy spring, drought and little rain; Summer is hot and the rain is concentrated; Autumn is cool and the temperature is moderate; Winter is cold, dry and snowy. The annual average temperature in Tianjin is11.4 ~ 12.9℃, the highest average temperature in urban areas is12.9℃, and it is the coldest in June, with an average temperature of-3 ~-5℃. It is the hottest in July, with an average temperature of 26 ~ 27℃. The monsoon prevails in Tianjin, with the maximum wind speed in winter and spring and the minimum wind speed in summer and autumn. The annual average wind speed is 2 ~ 4m/s, mostly southwest wind. The average frost-free period in Tianjin is 196~246 days, the longest frost-free period is 267 days, and the shortest frost-free period is 17 1 day. Among the four seasons, winter is the longest, 156~ 167 days; Summer comes next, 87~ 103 days; 56~6 1 day in spring; Autumn is the shortest, only 50~56 days. The average annual precipitation in Tianjin is 520 ~ 660mm, and the number of precipitation days is 63~70 days. In terms of regional distribution, there are more mountains than plains, and more coastal areas than inland areas. According to the seasonal distribution, the precipitation in June, July and August accounts for about 75% of the whole year. The sunshine time in Tianjin is long, with 2500~2900 hours of sunshine throughout the year.