Using the conventional meteorological data, automatic weather station data, SWAN (Sever Weather Automatically Nowcast System) products, and radar PUP products from the radar over the Sichuan basin, the evolution characteristics of radar echoes and the train effect of lineshaped (banded) echoes for 35 regional rain storms from 2010 to 2013 are analyzed by the statistical method. Results show that initial echoes form usually along the mountain areas at the edge of the basin in the afternoon or before midnight under the influence of topography and 850 hPa winds. The peak period of echo formation is 16:00 to 19:00 The formation mechanisms of lineshaped (banded) and massive echoes in the Sichuan basin are revealed. The heavy rain conceptual models are built for the west, north and southcentral parts of the Sichuan basin. It is the best time to release rainstorm warnings when the echoes become lineshaped (banded) or massive. The accuracy of rainstorm area warning is satisfactory, with the average warning lead time being 5 to 8 hours.