Analysis of a Torrent Rain Weather Process in Ningxia Occurring on 7～8th June 2002

By using routine meteorological data, numerical forecast products,satellite cloud photographs and radar echoes,applying synoptic analysis and diagnostic analysis methods,We analyzed the infrequent regional heavy rain which occurred in Ningxia on June 7～8th,2002.The results show that this heavy rain occurred under the favourable weather condition that the high center in the east while the low center in the west, this is a typical mixed precipitation weather. The main impact system is cold trough on 500hPa, low eddy shear line on 700hPa, lower troposphere jet in the southwest and surface occluded front. The relative stable condition which blocked in the east and the maintain of the southwest lower troposphere jet were the main reasons of this hard rain's maintain.