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In order to display the information content of these 51 ensemble rank values, we use a simplified anomaly representation. For this, 7 5 main anomaly categories were defined by the 10^th, 25^th, 40^th, 60^th, 75^th and 90^th percentiles, representing 7 categories from 5 categories of larger anomalies as 'Extreme low', 'Low, 'Near normal', 'High' and 'Extreme high'. For some products (namely the two maps and the hydrographs), the 5 main categories are extended to 'Extreme high'a 7-category version by sub-dividing the 'Near normal' category into 'Bit low, 'Normal' and 'Bit high' with the 40^th and 60^th percentiles. In the forecasts, each of these 7 categories will have a probability value, depending on how many of the 51 ensemble members they contain. for the maps and hydrographs, the three middle category anomalies are combined in a single anomaly. 

The overall expected anomaly category of the forecast is defined by the mean of the 51 ensemble member ranks (rank-mean), which represents a robust anomaly value without any random jumpiness. In addition, the uncertainty about these anomalies is also defined using the standard deviation of the 51 ensemble ranks (rank-std). Based on this rank standard deviation value, one of three uncertainty categories (low / medium / high) are assigned to the forecast.

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