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Charts available are: 2m temperature, surface temperature, total precipitation, mean sea level pressure, winds. 

Colouring on the charts is implies >90% significance for the anomaly.  This does not mean the white shading on the maps necessarily points to:

• a forecast of average.
• a 'don't know' forecast of climatology.

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• The chart displays the probability of the forecast anomaly lying in the upper half of the ER-M-climate distribution (i.e. above normal; warmer or wetter etc than the mean of the ER-M-climate). 

White on the plot means that either:

• the proportion of members above the ER-M-climate mean is between 40% and 60%,
• or that that proportion, whatever it is, is not statistically significant.

This plot structure circumvents the fact that some ER-M-Climate distributions will be skewed (i.e. the climatological probability of seeing more than the mean is far from 50%).can currently signify a number of different things - e.g. median of the forecast is about the same as the median of the re-forecasts. This fact that there are several potential interpretations can be confusing for users and ECMWF plans to offer improved products to address this later in 2024. 

Note: On precipitation charts the range of colours available for "below average" anomalies (brown colours) is constrained by the local climatology in the ER-M-climate.  For example if all ENS 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 brown shades.

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