摘要
此次过程主要影响系统是蒙古气旋,冷空气源地为中西伯利亚,经贝湖、蒙古发展加深形成蒙古低压并从西南开始影响黑龙江省。过程从2015年2月20日夜间开始至23日结束。黑龙江省共有40个观测点过程量达到暴雪级别,南部部分地区经历了比较明显的降水相态转换。分析最终得出:(1)锋区强弱以及位置是产生强降雪的关键,暖锋强于冷锋时易产生强降雪,冷锋强于暖锋时则降雪量级一般不大。(2)急流是大范围强降雪产生的必要条件,急流不仅提供了动力条件,与水汽源地联通后更成为重要的水汽条件。(3)中低层正涡度、中高层负涡度结构的稳定维持,使低层气旋性涡度环流增强,为强降雪天气提供了动力条件。
The process is mainly caused by the Mongolian cyclone, the middle of Siberian is the cold air source. Through the Baikal and Mongolia, the cold air transformed Mongolian low system and began to affect Heilongjiang Province from the southwest. The process began at the night of February 20, 2015 and ended at February 23. 40 observation stations reached snowstorm level in Heilongjiang Province. Parts of southern experienced a relatively significant precipitation phase conversion .Finally, the result shows that ：（1） The strength of the front area and the location is the key to produce heavy snowfall, if the warm front is stronger that cold front, it prone to cause heavy snowfall, else the snow is small.（2） The jet is a necessary condition for wide range of heavy snowfall, the jet not only provides dynamic conditions but also become an important water vapor condition after connect with water vapor resource.（3） The stable maintenance of positive vorticity in the lower and middle and negative in upper and middle level enhance the circulation of the low level cyclone, and provided the dynamic conditions for the strong snowfall weather conditions.
出处
《黑龙江气象》
2016年第1期9-12,共4页
Heilongjiang Meteorology
关键词
暴雪
降水相态
snowstorm
precipitation phase
