When is the weather warm in Beijing?

According to meteorological weather, there are four seasons: when the average temperature of the day is above 10℃ for five consecutive days, it means the arrival of spring.

In the history of Beijing, this standard was generally reached at the beginning of April in the solar calendar.

Beijing agricultural proverb says: "Don't shoot in September, walk on the ice in March and April, watch the green willows along the river in May and June, open the river in July and September, geese come in August and September, catkins land in September, and cows travel everywhere." Historically, the spring climate in Beijing was in the late March of Gregorian calendar (starting on March 23rd and 4th), and the temperature was basically stable above 10 degrees in the early April of Gregorian calendar.

In other words, it basically takes nearly two months.