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Fig8.1.9.3-5:  An example CDF for snowfall - snowfall is just considered as equivalent rainfall.   Moderately large positive EFI shows the equivalent rainfall distribution is higher than the M-climate distribution.  The positive upper tail SOT (quantile 90) indicates there are several ensemble members predicting extreme equivalent rainfall anomalies anomalies (above the 99th ER- M-climate percentile shown by the dashed green line).  This suggests uncertainty that a significant equivalent rainfall is forecast (only moderate EFI).  50% of ensemble members forecast less than about 1mm precipitation (the lower part of the M-climate is only just above 0mm).  But 25% of ensemble members forecast more than about 2mm precipitation (significantly above M-climate where about 97% of precipitation less than 2mm).  If a significant snowfall occurs it could be an exceptional rainfall equivalent (fairly high SOT value of 0.8).  Confidence in extreme precipitation rises as SOT values increase - users should focus on SOT values >0.5.

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Fig8.1.9.3-7: An example of a rainfall CDF most frequently encountered where very few ensemble members forecast any rain at all.  The small negative EFI shows the ensemble rainfall distribution is lower than the M-climateClimate distribution.  The negative upper tail SOT (quantile 90) indicates there are very few if any ensemble members (and in this case none of them) predict extreme equivalent rainfall (above the 99th ER-M-climate Climate percentile shown by the dashed green line).  This suggests confidence that larger than normal rainfall will not occur (small EFI) and an exceptional rainfall event will not occur(SOT -1.2).

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