The analysis of phase change of precipitation in Liaoning in spring 2010

Three cases of precipitation in spring 2010 are analyzed by using synoptic information, automatic weather stations data, NCEP reanalysis data (1° × 1°), and real-time weather report in Liaoning. The results show that the cold air's route and strength can be used to estimate the area of phase change of precipitation initially. When phase change of precipitation occurs, we should pay attention to these situations as follows: the pressure in center of anticyclone is larger than 1040 hPa; level of 0°C lower than 925 hPa; the temperature of 850 hPa, 925 hPa, 1000 hPa and surface is below -4°C, 0°C, 2°C, 4°C, respectively.