Must Surprise Snowstorms be a Surprise?

  • M. Steven Tracton
Part of the Meteorological Monographs book series (METEOR, volume 33, No. 55)


Today, even with state-of-the-art observational, data assimilation, and modeling systems run routinely on supercomputers, there are often surprises in the prediction of snowstorms, especially the “big ones,” affecting coastal regions of the mid-Atlantic and northeastern United States. Little did the author know that lessons from Fred Sanders’ synoptic meteorology class at the Massachusetts Institute of Technology (1967) would later (late 1980s) inspire him to pursue practical issues of predictability in the context of the development of ensemble prediction systems, strategies, and applications for providing information on the inevitable case-dependent uncertainties in forecasts. This paper is a brief qualitative and somewhat colloquial overview, based upon this author’s personal involvement and experiences, intended to highlight some basic aspects of the source and nature of uncertainties in forecasts and to illustrate the sort of value added information ensembles can provide in dealing with uncertainties in predictions of East Coast snowstorms.


Ensemble Forecast Ensemble Prediction System National Weather Service Quantitative Precipitation Forecast Mesoscale Predictability 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© American Meteorological Society 2008

Authors and Affiliations

  1. 1.Office of Naval ResearchArlingtonUSA

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