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THIS NEEDS IMPROVING

1. How does the ensemble mean compare to the HRES forecast and analysis?
2. Note the diversity in the ensemble and how the ensemble spread develops - are there any clusters of forecasts developing? (use the different visualisation techniques). What features are there in the ensemble? What do the extreme forecasts look like?
3. Are there any members that provide a better forecast? Is it possible to see why these forecasts are better?
   
   

Please refer to the handout showing the storm tracks labelled 'ens_oper' during this exercise. It is provided for reference and may assist interpreting the plots.

Each page shows 4 plots, one for each starting forecast lead time. The position of the symbols is the storm centre valid for 28th Oct 2013 at 12Z. The colour of the symbols is the central pressure.

The actual track of the storm from the analysis is show as the red curve with the position at 28th 12Z highlighted as the hour glass symbol. The control forecast for the ensemble is shown as the green curve and square symbol. The lines show the 12hr track of the storm; 6hrs either side of the symbol.

Note the propagation speed and direction of the storm tracks.  The plot also shows the centres of the barotropic low to the North.

Q. What can be deduced about the forecast from these plots?