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On sub-seasonal range web charts the confidence is "over-stated", because reliability diagrams consistently show that forecasts are over-confident.  Thus where a high probability of a particular type of event is predicted, the "true" chances of that event happening are actually less than the probability that is shown. 

A particular consideration when using the precipitation charts is that the range of colours available for "below average" anomalies (red colours) is constrained by the local climatology in the ER-M-climate.  For example if all ensemble members showed a dry week, the mean (-ve) anomaly could be no larger in magnitude than the mean in the ER-M-climate.  So in some locations the strongest dry signal one can ever see will only be in the first or the second of the red shades.

Anomaly charts (500hPa N Hem anomaly and Global and Regional anomaly) show how sub-seasonal range forecasts performed in the recent past in the lead up to a particular week.  The anomaly of one week of forecasts (relative to the ER-M-climate) is compared with the weekly mean anomalies (relative to the ER-M-climate) of recent sub-seasonal range forecasts verifying over the same period.   They give information about the consistency between the monthly forecasts from one week to another.

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