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• is run twice daily, base times 00 UTC and 12 UTC, producing a 10 day forecast (Day0 to Day10) and also a 15 day forecast (Day0 to Day15). 
• has horizontal resolution of 9 Km and vertical resolution of 137 model levels.  These values are the same as those of the High Resolution (HRES) in IFS versions before Cy48r1).
• has land-atmosphere and ocean-atmosphere coupling.
• has 50 ensemble members plus an unperturbed control member (CONTROL-10 for the 10 day forecast, CONTROL-15 for the 15 day forecast).
• CONTROL-10 is the unperturbed ensemble member and corresponds to the High Resolution (HRES) in earlier IFS versions before Cy48r1.

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The medium range 10 day and 15 day ensemble forecasts run with data analysed from the short cut off data analysis (SCDA).  

When averaged over many forecasts each of the perturbed members has lower skill than the control member though any individual forecast might show a higher skill.  There is a range of products to present the information from the ensemble in different ways and appropriate for different uses.  These include probabilities, clusters of alternative scenarios, and tropical cyclone and extra-tropical cyclone products.  Certain important products are based on, or directly show, anomalies relative to the M-climate, such as meteograms and the Extreme Forecast Index and Shift of Tails (EFI/SOT).    The ENS products and chart presentations show where and when weather may deviate from the average for the location and time of year, and if such an anomaly could be extreme.

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