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The GRIB file fc_oper.grib contains the operational forecast run at 7 August 00 TC UTC (four 4 days before the event). Drag it into the top right map and customise it in the same way as the previous plot. You will see that the wind storm was not present in the forecast.
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The GRIB file fc_ens.grib contains the control forecast member and the 50 perturbed members of the ENS run at 7 August 00 TC UTC (four 4 days before the event). We will compute and visualise the mean of the ensemble members using a Macro.
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Drag your Macro into the bottom left map and customise it with the wgust_shade Contouring icon. You would also need a custom Text Plotting icon. Take a copy of the one used for the previous plots (called title_oper) and tailor it to your needs. When you analyse the plot you will notice that the ensemble mean hints for higher wind gusts in the our area of interest.
Visualising the ensemble spread
The ensemble spread is the standard deviation of the ENS members. We can compute it in a very similar way to the ensemble mean. The only difference is that this time you we need to use the stdev() function instead of mean(). Now it is your task to write a Macro for it. Once you finished your Macro drag it into the bottom right map and customise it with the wgust_spread_shade Contouring icon and with a custom Text Plotting icon. You will see that the ensemble spread is fairly high in the investigated area.
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