Analysis of the June 2021 Atmospheric Circulation and Weather
The main characteristics of the general atmospheric circulation in June 2021 are as follows. There was one polar vortex center with stronger strength than normal in the Northern Hemisphere. The 500 hPa geopotential height over Europe was stronger than normal. The western Pacific subtropical high moved northward during middle dekads of this month and then southward in the last dekad. In June, the monthly mean precipitation of China was 91.5 mm, which was less than the normal by 8%. The negative precipitation anomaly reached 20%-50% in most part of Jiangnan, north part of South China and Jianghuai Region. In some regions the negative anomaly exceeded 50%. However, the positive precipitation anomaly reached more than 50% in northern Inner Mongolia, western Heilongjiang Province and eastern Jilin Province as well as central and eastern Liaoning Province. The monthly mean temperature of China was 20.8℃, which was a little higher than the usual. However, it was even 2℃ warmer than the normal in northern Henan Province, central Jiangsu Province and southern Qinghai Province. In June, eight regional torrential rain processes which mostly occurred in South China, and the observed values at many stations reached the standard of extreme precipitation events. Two typhoons were generated and neither of them landed in China in June. There were 44 stations where extreme high temperature events occurred and these stations are mostly located in the regions of Huanghuai, Jianghuai and South China. In addition, the daily maximum temperature at four stations broke the historical record.