After analysing of cases wind and without severe convective precipitation, fourteen factors, which have special indication in a short time before precipitation, have been screened out by using the significance test method from sounding data at a single station. More remarkable instructive seven factors denoting the convective instability, conditional instability, contents of moisture, and homogeneity of atmosphere vertical stratification for torrential rains are given. These factors can apply to the short-range forecast for the severe precipitation