Abstract:In order to enhance the prediction accuracy of 0-2 h now-casting of short-time heavy precipitation and thunderstorm gale, this paper proposes a severe convection probability now-casting method based on the vertical profile characteristics of the dual-polarization radar (referred to as the CSCPVP method). By using the improved Bayesian probability method, the vertical profile characteristics of polarization radar of two types of severe convection disasters are introduced into the extrapolation model to realize the advanced identification of severe convection attributes, and the broad constraints of regional model prediction are integrated to ensure that the proximity extrapolation prediction results of severe convection are more consistent with the actual dynamic and microphysical characteristics. The evaluation results of the entire flood season (June-September 2023) in Zhejiang show that the CSCPVP method has significantly improved 0-2 h now-casting ability of two types of severe convection than the existing operational methods. The new method significantly improves 0-2 h now-casting ability of systematic, local and distributed classified severe convection (the critical success index of short-time heavy precipitation increases from 8%-16% to 22%-26%; The critical success index of thunderstorm gale was increased from 7% to 10%-11%), which effectively improved the problem of false alarms and missing prediction.