Analyze the statistical charts of weather changes in Nanchang City, Jiangxi Province in the days before and after May 5, and answer questions 3 to 6 to reflect the weather system diagram: (　)

According to the meaning of the question, the weather system shown in the picture is a cold front passing through.

A. The warm air mass is powerful and pushes the front to move to the side of the cold air mass, forming a warm front, so it does not meet the meaning of the question;

B. The cold air mass is powerful and pushes the front to the side of the cold air mass. The front formed by the movement of the warm air mass on one side is a cold front, so it does not meet the meaning of the question;

C. The picture shows an anticyclone in the southern hemisphere, so it does not meet the meaning of the question;

D. The picture shows a cyclone in the Northern Hemisphere, so it does not fit the meaning of the question.

So the answer is: B.