边界层急流在一次大雪过程中作用分析

Analysis of the Role of Boundary Layer Jet Stream in a Heavy Snow

摘要: 本文利用常规观测资料、NCEP 1˚ × 1˚再分析资料对2019年2月13~14日大雪过程预报过程分析，发现传统的西风槽带来的弱降雪过程预报思路被打破，低层暖湿气流沿着边界层冷垫倾斜上升，动力抬升作用导致降雪增强，并且雪带的分布呈罕见的东南–西北走向，雪带分布和水汽通道、急流走向等相关物理量的走向一致，为今后避免此类大雪过程预报失误提供了预报思路。

Abstract: This paper, by using conventional observation data, the NCEP 1˚ × 1˚ reanalysis data on February 13~14, 2019, heavy snow forecast process analysis, found that the traditional westerly trough prediction ideas of weak snowfall process are broken; The low-level warm and wet air sloped up along the boundary layer cold cushion, and the dynamic uplift enhanced the snowfall. Moreover, the distribution of snow belts shows a rare southeast to northwest trend, which is consistent with the trend of water vapor channel, jet stream and other related physical quantity, which provides a forecasting idea for avoiding the prediction error of such heavy snow process in the future.