A fingerprinting technique for major weather events

To address the challenge of weather forecasting, pattern recognition and forecast analogs offers the fingerprinting method. This approach differs in analog forecasting in that it follows a perfect-prog method searching the forecast fields rather than the current analysis for analogs. It is based on the concept of weather types as a series of generalized synoptic situations or patterns usually presented in chart form. The weather types are selected representing typical pressure and frontal patterns and were originally devised as a method for lengthening the effective time range of forecasts. The most clear-cut results are from heat waves and snowstorms with limited output from flooding and thunderstorm wind events. However, the forecast skill of the model depends in large measure on the underlying numerical weather prediction (NWP) model rather than on the subsequent application of analogs.