Cause Analysis of Cold Wave Weather on April 2, 2011 in Lushi County

doi:10.3969/j.issn.1673-7148.2012.02.014

Abstract：Based on the conventional weather data and numerical forecast products, with weather analysis and diagnostic analysis method, the weather process of cold wave occurred in Lushi from March 31 to April 2, 2011 were analyzed. The results showed that： the cold wave is small trough eastward development type. On 500 hPa map, cold center near Novaya Zemlya is lower than -40 莫爱勰 , the temperature trough is behind height trough, the same phase of south trough and north trough merge and strengthen to make unstable small groove into the East Asia major trough. The formation the warm inverted trough located in Hetao and Changjiang-huaihe cyclone will help the cold wave cold front to accelerate southward. The strong cold advection and surface prophase warm inverted trough provided favorable temperature conditions for the strong cooling temperature. The single station meteorological elements reflect well on the cold wave, regardless of the pressure, temperature and anomalies changes, or process before the rise of temperature are important indicators of cold wave forecast. The forecasting of EC 850 hPa temperature field has good indication to judge whether the cold weather or not; the strung cold adveetion at 850 hPa is the main reason for cold wave weather.