Abstract:The main features of the atmospheric circulation in November 2024 are as follows. The polar vortex in the Northern Hemisphere exhibited a dipole pattern, with the primary center located in the region from north Asia to the area east of Novaya Zemlya, stronger than the long-term average for the same period. The Eurasian mid-to-high latitudes gradually transitioned from a “two ridges and one trough” pattern to a “two troughs and one ridge” pattern. China’s mid-to-high latitudes were controlled by a weak meridional circulation and a high-pressure ridge with fewer upper-level trough activities, resulting in less frequent and weaker cold air processes affecting China, so the national average temperature was significantly higher than normal. The subtropical high was stronger. In November, the national average temperature was 5.2℃, 1.9℃ higher than the long-term average, making it the warmest November since 1961.
The national average precipitation was 21.2 mm,
5% more than that in the same period of normal years. The first cold wave and snowfall weather process occurred in the last dekad of November. Additionally, there were 4 typhoons generated in the Northwest Pacific and the South China Sea in November, 1.8 typhoons more than before. As the result of the static weather condition, there were three fog haze events in November.