Extended-Range Probability Forecasts Based on Dynamical Model Output

Abstract A probability forecast has advantages over a deterministic forecast as the former offers information about the probabilities of various possible future states of the atmosphere. As physics-based numerical models find their success in modern weather forecasting, an important task is to convert a model forecast, usually deterministic, into a probability forecast. This study explores methods to do such a conversion for NCEP’s operational 500-mb-height forecast and the discussion is extended to ensemble forecasting. Compared with traditional model-based statistical forecast methods such as Model Output Statistics, in which a probability forecast is made from statistical relationships derived from single model-predicted fields and observations, probability forecasts discussed in this study are focused on probability information directly provided by multiple runs of a dynamical model—eleven 0000 UTC runs at T62 resolution. To convert a single model forecast into a strawman probability forecast (single ...

[1]  Jeffrey L. Anderson.  A Method for Producing and Evaluating Probabilistic Forecasts from Ensemble Model Integrations , 1996 .

[2]  R. Reynolds,et al.  The NCEP/NCAR 40-Year Reanalysis Project , 1996, Renewable Energy.

[3]  Robert L. Vislocky,et al.  Improved Model Output Statistics Forecasts through Model Consensus , 1995 .

[4]  H. V. D. Dool,et al.  Low-Frequency Anomalies in the NMC MRF Model and Reality. , 1995 .

[5]  H. M. van den Dool,et al.  On the Weights for an Ensemble-Averaged 6–10-Day Forecast , 1994 .

[6]  Eugenia Kalnay,et al.  Ensemble Forecasting at NMC: The Generation of Perturbations , 1993 .

[7]  Eugenia Kalnay,et al.  Operational Ensemble Prediction at the National Meteorological Center: Practical Aspects , 1993 .

[8]  A. Mai,et al.  Identification of Highly Predictable Flow Elements for Spatial Filtering of Medium- and Extended-Range Numerical Forecasts , 1993 .

[9]  Franco Molteni,et al.  Regimes in the wintertime circulation over northern extratropics. II: Consequences for dynamical predictability , 1990 .

[10]  M. Steven Tracton,et al.  Predictability and Its Relationship to Scale Interaction Processes in Blocking , 1990 .

[11]  Robert E. Kistler,et al.  Dynamical Extended Range Forecasting (DERF) at the National Meteorological Center , 1989 .

[12]  E. Klinker,et al.  Systematic errors in the baroclinic waves of the ECMWF model , 1986 .

[13]  J. Wallace,et al.  Teleconnections in the Geopotential Height Field during the Northern Hemisphere Winter , 1981 .

[14]  M. Déqué.  Ensemble size for numerical seasonal forecasts , 1997 .

[15]  Jeffrey L. Anderson,et al.  Selection of Initial Conditions for Ensemble Forecasts in a Simple Perfect Model Framework , 1996 .

[16]  Franco Molteni,et al.  Ensemble prediction using dynamically conditioned perturbations , 1993 .