Pseudo-precipitation: a continuous variable for statistical post-processing
While forecasts of continuous variables lend themselves to straightforward statistical post-processing techniques such as Model Output Statistics, precipitation is usually dealt with in a 2-step process. Considering the processing of ensemble data, in the first step, a sample of single or ensemble precipitation forecasts are compared with observations considering the occurrence of precipitation to derive a Probability Of (>= .01 inch) Precipitation (POP) forecast. Then, in a second round of analysis, forecasts with non-zero precipitation are compared with observations to derive the Probability Distribution of Precipitation (PDP), conditioned on precipitation being above zero. In this presentation, a continuous variable related to precipitation is introduced to overcome some limitations in statistical post-processing associated with the discontinuous nature of precipitation.