People brave the autumn snow under umbrellas in Harbin, Northeast China's Heilongjiang Province on October 19, 2025. Photo: IC

Monitoring data from China's National Climate Centre (NCC) show that China entered a La Nina state in October this year, a development expected to raise the risk of a prolonged drought throughout the winter-spring period under continued La Nina conditions, China Central Television (CCTV) reported on Sunday.

La Nina refers to the abnormal cooling of sea surface temperatures over the eastern and central equatorial Pacific Ocean for a sustained period, CCTV News reported.

Continued La Nina conditions are expected to have some impact on China's climate, CCTV News reported. 

According to Zhang Daquan, deputy director of the climate prediction division of the NCC, La Nina is expected to trigger northeasterly winds on the northwest side of the Northwest Pacific and the South China Sea, suppressing the transport of tropical moisture to China in the winter and causing below-average rainfall in eastern and southern regions. 

Based on earlier forecasts, East China and South China are forecast to suffer from a continuous winter-spring drought this year, Zhang added.

Under the continued influence of external forcing factors such as the La Nina state in the central and eastern equatorial Pacific Ocean and below-average Arctic sea ice, most regions across China are expected to see winter temperatures close to or slightly above the seasonal average this year, with significant fluctuations between cold and warm periods. 

Provinces including Hunan, Hubei, Guizhou, Sichuan and Shaanxi are likely to experience periods of low temperatures accompanied by rain, snow and icing, CCTV reported. 

A La Nina state does not necessarily constitute a La Nina event, CCTV reported. 

According to Zhang, meteorologists define a La Nina state as occurring when the Nino 3.4 index drops below minus 0.5 C, indicating cooling in the central and eastern equatorial Pacific Ocean. 

However, a La Nina event is defined as occurring when the Nino 3.4 index remains below minus 0.5 C for five consecutive months, according to national standards, CCTV reported. 

Because of a weak La Nina event occurred earlier this year, public speculation has arisen over the possibility of a double La Nina event this winter. 

Expert explained that the so-called double La Nina does not mean that two La Nina events occur within the same year; rather, it refers to La Nina conditions persisting through the winter for two consecutive years. Therefore, the NCC has forecast a low probability of a double La Nina this winter, according to the report.


Global Times