Group 1 - The article discusses a significant temperature drop in southern China due to a cold air mass, with some areas experiencing a temperature decrease of over 12°C within 24 hours [1][3] - Specific regions such as Fujian, Jiangxi, and Guangdong are highlighted as experiencing the most substantial temperature drops, with Fujian Jianing seeing a drop of 17.4°C [1][3] - The cold air mass is expected to reach its lowest point tomorrow morning, with the 0°C line moving southward to northern Fujian and northern Hunan [1] Group 2 - Following the cold air mass, a warming trend is anticipated in the central and eastern regions of China, with northern areas expected to see a temperature increase of up to 20°C [3] - The article notes that the highest temperature in Shenyang is projected to rise from -12°C to 8°C, indicating a cumulative increase of 20°C [3] - The overall weather pattern for the next 10 days suggests warmer conditions across most of the country compared to historical averages [5] Group 3 - Rain and snow are expected to decrease temporarily due to the cold air mass, but a new wave of precipitation is forecasted to begin tomorrow, although the intensity is expected to be generally weak [5][7] - The central meteorological forecast indicates multiple occurrences of light to moderate rain or sleet in regions such as Jianghuai and northern Jiangnan over the next 10 days [7] - Areas like eastern Guizhou, southwestern Hunan, and northern Guangxi are predicted to experience frequent rainfall in the coming days [9] Group 4 - The formation of the "Wuyi Mountain trapped front" is explained as being closely related to the terrain, where the Wuyi Mountains block the cold air from advancing southeast [11] - The article describes how the cold air interacts with the topography, leading to the development of the trapped front, which affects the weather patterns in the region [11]