Analysis on a Cold Wave Process in 2006 Spring in Hotian Area

The strong sandstorm and cold wave weather process were occurred from the west toward the east in Hetian area during Apr.9～11,2006.This tractate carries out analysis on the aspects of weather process,such as the synoptic situation,the main elements of each station and the dynamic diagnostics etc..The result indicated: as a predominant system,Ural mountain high pressure ridge developed and as a synoptic scale influence system,Siberia trough deepens to be the main reason for this weather process.But the hot low-pressure of medium scale born and developed in native area to be the inspired effect for abrupt strong sandstorm.This strong sandstorm appeared in the starboard of jet stream axis at upper air,the positive vorticity,and the leeward of negative temperature advection centre and the area of stronger updraft with low layer convergence and high layer divergence.Applying ECMWF numerical forecast product for this weather process,the forecast and service of this weather were made accurately and duly ahead 3 days,in the person of the excellence to numerical forecast.