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• Make good use of the ensemble, especially (but not only) at longer lead-times.
   
• Give more weight to the more recent forecasts, but don't exclude results from previous runs.
• Larger spread implies larger errors.
• Jumpiness is not a good indicator of likely error.
• Dynamical sensitivity can increase jumpiness at short ranges and should be investigated.
  
• Do not extrapolate trends.
• Make more use of the ensemble mean (EM), rather than the ensemble control (CTRL) or HRES, especially at longer lead times (say ≥ ~ 4 days), to reduce jumpiness.
• At short ranges the ensemble mean (EM) and control CTRL tend to “jump together” more often, so the strategy of following the EM, rather than CTRL (or HRES), is less beneficial at those ranges.
• Note that strong gradients are always weakened in the ensemble mean (EM).
• Consider each case according to the synoptic situation and other aspects (eg timing, rapid development).
   

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