Based on the numerical prediction interpretation techniques and forecast experiences，the short － term objective forecast system
of meteorological elements for Northwest China is established． With the aid of meteorological data of real － time observation，the
verification and assessments of objective forecast from the system － output for air temperature and precipitation in winter of 2006 have
been performed． The results show: ( 1) The forecast accuracy of maximum and minimum temperature is much higher than that of precipitation
with the accurate rates of 70% and 34%，respectively． ( 2) The factors affecting the forecast accuracies of temperature and
precipitation are the static stability of atmosphere and relative humidity． ( 3) If the system established on month scale，the forecast accuracy
of temperature is expected to have a 10% improvement．

New GenerationWeather Radar has become a chief means of monitoring the severe convective weather events occurred in Lanzhou and its surrounding areas. This paper analyzed data error sources in radar front - end and back - end p rocessing. Itwas found that clutter, radar antenna gain, monitoring distance and data interpolation, coordinate conversion, remote transmission to several ter2 minals are mainly error sources in radar front - end and back - end p rocessing, respectively.