Application of mesoscale model MM5 to a cold front weather system

Using the mesoscale model MM5, the cold front in South China and East China from March 6 to 9, 2001 was modeled. There is 2 to 4 hour lag between the simulation movement of the cold front and the observation result. The simulated result of sea level pressure agrees with the observed data. The time series near-surface simulation wind velocity is larger and wind direction is more northerly than the observation result from 35th to 40th hour in 3 stations in Hong Kong, but as a whole the two results are accordant. The simulation equivalent potential temperature shows the position of the cold front moved southward. The numerical results of the geopotential height and wind fields in 500hPa and 850hPa show that the high pressure in north, and northwest China was strengthened and moved south and the low pressure in Southwest China and Middle China was weakened. The trough of low pressure provided some power for the movement of the cold front to a certain extent and the front speeded up the disappearance of the trough of the low pressure.