Visibility and Fog Forecasting Based on Decision Tree Method

The paper describes a visibility and fog forecasting model developed and used at the Hungarian Meteorological Service (HMS) for last 3 years. The investigated model is a perfect prognostical model (PP). Characteristics of the model, such as input data, statistical approach, decision trees and threshold numbers, are described in this paper. The model was tested for both measured sounding and predicted data. The verification of the model led to very good results, so it was applied to aeronautical forecasting as well as to nowcasting. Information and short review about different type of other visibility models are also given. Key-words: NWP parameters, perfect prognosis(PP), model output statistics (MOS), FOGSIindex, decision tree.