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• Ensemble output is shown for individual ensemble members for a few parameters, but more importantly ensemble output showing a selection of individual and combined parameters is presented in a probabilistic or multi-valued format.               Charts available:
  • Forecast charts (surface and upper air) - showing a selection of individual and combined parameters, to 15days forecast lead-time.
    • Postage stamp charts - to show the output of all ensemble members for a few parameters at several forecast lead-times. (Example chart).
    • Mean and Spread charts - to place the uncertainty measured by the standard deviation of the members of the latest ensemble into the context of recent uncertainty in the ensemble forecasts.  (Example chart).
    • Probability charts - to show probabilities of events exceeding a given threshold (e.g. rainfall > 5mm/day).  (Example chart).
    • Extreme Forecast Index charts (including clickable multiparameter charts) - to highlight areas where forecast values depart significantly from M-climate. (Example chart).
    • Plumes, Meteograms, EFI-CDF, Vertical Profiles - to give probabilistic interpretation of the ensemble for specific locations with optional M-climate data to emphasize departure from the re-forecast climatology.   
    • Cluster charts - to distil ensemble member output into groups exhibiting similar large-scale patterns enabling assessment of most likely results (i.e. possible 'weather scenarios').  (Example chart).
    • Tropical cyclone activity charts (including genesis) - to indicate tropical cyclone threats worldwide. (Example chart).

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• Model diagnostic output is shown to allow the user to assess the impact of the latest observations or the modelled state of the underlying surface of the earth.
  Charts available:
  • Analysis increment charts - to allow identification of sources of potential problems in the forecast evolution.  (Example chart).
  • Surface parameter charts - to indicate the surface conditions used by ensemble control runs that govern radiation and other exchanges with the atmosphere.  These allow the user to assess any shortcomings (e.g. insufficient snow cover, soil moisture, leaf area index etc). (Example chart).

Extended range ensemble (16-

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46 day forecast period)

Extended range ensemble products are derived from an extension of the normal 15 day ensemble twice per week on Mondays and Thursdays and act as a bridge in time between ensemble forecasts and seasonal forecasts.  The charts available cover week-long periods (i.e. 7day 7-day periods after the data time of the forecast run, going up to Day28 or 32day46).
Charts available:

• Weekly mean anomaly charts - to highlight areas where mean forecast values depart significantly from the ER-M-climate for each location within the chart area. (Example chart).
• Weekly probability anomaly charts - to highlight the probability of differing from the ER-M-climate mean for each location within the chart area. (Example chart).
• Weekly tercile probability charts - to show the probability the weekly mean anomalies will be in lower and upper third of the ER-M-climate for each location within the chart area. (Example chart).Weekly multiparameter outlook charts.
• Weekly averages of the monthly forecast ensemble for several variables on a single chart. (Example chart).Monthly forecast plumes for a selection of European cities. (Example plume).
• Postage stamp charts - to show the output of all EPS members for a few parameters at several forecast lead-times. (Example chart).
• Weather regime clusters and weather regime time series (based on six seasonal climatological regimes) - to show the more probable flow patterns and predicted changes from one type to another. (Example cluster chart, example time series chart).
• Tropical cyclone probability charts (including genesis) - to indicate tropical cyclone threat and intensity worldwide and compare with tropical cyclone frequency and intensity in the ER-M-climate. (Example chart).
• Time-longitude (Hovmoeller) diagram of the observed and forecast ensemble mean anomaly of 500hPa or 1000hPa geopotential (in dam) in the extra-tropics - to show persistence and progression of disturbances and potential interaction between upper and lower features. (Example diagram).
• Madden-Julian Oscillation (MJO) index metrics and Wheeler-Hendon MJO diagram - to show recent and forecast evolution and uncertainty of MJO features. (Example MJO index metrics Hovmoeller diagram, example Wheeler-Hendon MJO diagram).

Long Range or Seasonal ensemble (

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7 to 13 months period)

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:

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