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By analyzing the wind profiler data on two different snowy weather processes on 31 October and 9 November 2009 in Beijing. It is found: (1) The easterly flow established at lower levels 2 hours before the start of snowfall, and there occurred a phenomenon that the wind suddenly strengthened, which has reference value for forecasting the start of snowfall. (2) There existed cold advection at 700 hPa and above, or cold advection enhancement, which is also a sign of the snowfall start. (3) The profiles of temperature advection calculated from the wind profile data can reflect the atmospheric stability conditions and provide a reliable basis for determining whether the snow is convective. Therefore, it has great significance for critical weather nowcasting to strengthen the wind profile and temperature advection profile monitoring.