Subtropical high drives unusually heavy Beijing rains

According to an expert from the Beijing Meteorological Observatory, the recent heavy rainfall over the city is attributable to an unusual northward shift of the subtropical high-pressure system.

From Monday night to Tuesday morning, the city experienced intense downpours, with heavy rain affecting the entire area and parts of Fangshan district facing extreme storms.

Rainfall is expected to continue across most of Beijing on Tuesday, with some regions experiencing severe showers that could lead to localized torrential downpours.

As of Monday midnight, the average precipitation in the capital reached 165.9 millimeters, with the heaviest rainfall recorded in Langfangyu and Zhujiaoyu in Miyun district.

He Na, chief forecaster at the Beijing Meteorological Observatory, told Beijing News that since July 24, the subtropical high has remained abnormally north and stable, triggering frequent rains along its edge.

From July 24 to July 25, heavy rain fell citywide, and on the evening of July 26, northern areas faced extreme downpours. These events were driven by a warm, moist southwest airflow typical of subtropical monsoon rainstorms, said the forecaster.

On Monday night, Beijing was affected by a different weather system, a long trough of westerly winds moving from north to south. This system moved uniformly across the city, resulting in widespread rainfall, the expert explained.

According to statistics released by the observatory, since the start of the rainy season on June 1 until 8 am on Tuesday, Beijing has received 420.8 millimeters of rain. It is 74.8 percent above the average 240.7 millimeters for this period, and 84.4 percent more than the same time last year.

Beijing's meteorological authorities forecast that the current widespread heavy rain will gradually weaken and end by Wednesday, with intense showers shifting eastward.