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The overall expected anomaly category of the forecast (one of the 7, shown as colour in the map and highlighted in the pop-up table5 categories, shown by colours in the river network and basin summary maps and in the hydrograph in the pop-up window; and one of 7 categories highlighted in the probability evolution table in the pop-up window) is defined by the 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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