Abstract:In April 2025, the Northern Hemisphere polar vortex exhibited a monopole with an eccentric distribution and was stronger than normal. Over the Eurasian mid-to-high latitudes, the circulation pattern featured a pattern of “two troughs and one ridge”. The ridge between the East European trough and the East Asian trough was broad and flat. The national average temperature across the whole China was 13℃, which is 1.5℃ higher than the climatological average (11.5℃) in the same period. The national average precipitation was 38.9 mm, 11% less than the climatological average (43.6 mm). The main precipitation areas were located in Jiangnan and the northern parts of South China. The precipitation of Eastern Inner Mongolia and Northeast China was above the normal level. During this month, there were five major sand-dust processes, two cold air, three heavy rainfall processes, and four severe convective weather processes. Notably, the strong sandstorm process from 10 to 14 April was characterized by its long duration, high intensity and extensive dust coverage. This event was also accompanied by widespread strong winds and a significant drop in temperature.