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Long-range or Seasonal forecast charts are derived from an ensemble (separate from the extended range ensemble) run on the 1st of each month out to 7 months, extended to 13 months each quarter (i.e. every 3 months).   The charts available mostly cover 3-month periods, with the first valid period typically beginning 1 month after data time.
Charts available:

• Monthly mean probability of anomaly charts - to highlight areas where ensemble forecast values depart significantly from the S-M-climate for each location within the chart area. (Example chart).
• Climagrams - box and whisker diagrams comparing the distributions of parameter averages within pre-defined regions:
  • as forecast by the seasonal ensemble,
  • as represented in the S-M-climate re-forecasts,
  • and as represented in re-analyses.
    (Example climagram).
• Tropical storm probabilities and anomalies against S-M-climate. (Example chart).
• Niño plumes - show the range of seasonal forecasts of sea-surface temperature over pre-defined regions of equatorial Pacific. (Example plume).

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