Verification of the Deterministic and Probabilistic Radar Nowcasting of Precipitation in Warm and Cold Seasons in the European Part of Russia

Comparative quality analysis of ensemble radar precipitation nowcasting based on the test results for the warm (May–September 2020) and cold (November 2021–March 2022) seasons is presented. The composite precipitation intensity fields obtained from radar observations serve as control data for verification. In both periods, a slight but systematic advantage of the forecasts from the mean ensemble field is revealed, which indicates the expediency of using even small-volume ensembles. For all the skill scores used (except for the frequency bias), forecasts in the cold season turn out to be better than forecasts in the warm one, however, the sample sizes for verification in the cold season may be significantly lower than the corresponding sample sizes in the warm one. The problems of comparative quality analysis that are caused, in particular, by the loss of spatial connectivity of the composite field during the cold season are discussed.