We investigate the characteristics and mechanisms of persistent wet-cold events (PWCEs) with different types of cold-air paths. Results show that the cumulative single-station frequency of the PWCEs in the western part of South China is higher than that in the eastern part. The pattern of single-station frequency of the PWCEs are “Yangtze River (YR) uniform” and “east–west inverse”. The YR uniform pattern is the dominant mode, so we focus on this pattern. The cold-air paths for PWCEs of the YR uniform pattern are divided into three types—namely, the west, northwest and north types—among which the west type accounts for the largest proportion. The differences in atmospheric circulation of the PWCEs under the three types of paths are obvious. The thermal inversion layer in the lower troposphere is favorable for precipitation during the PWCEs. The positive water vapor budget for the three types of PWCEs mainly appears at the southern boundary.

我们研究了不同类型冷空气路径的持续性湿冷事件（PWCE）的特征和机制。结果表明，华南西部地区PWCE的累计单站频率高于东部地区。 PWCE单站频率呈现“长江均匀”和“东西反演”的格局。 YR制服图案是主导图案，所以我们重点关注这个图案。 YR均匀型PWCE冷空气路径分为西型、西北型和北型三种类型，其中以西型所占比例最大。三种路径下PWCE的大气环流差异明显。对流层低层的逆温层有利于PWCE期间的降水。三种PWCE的正水汽收支主要出现在南部边界。