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In GRIB1, parameters that are statistically processed over a time window, such and maximum, minimum and average values over the last 3 or 6 hours, have different paramIds for each time window available. In GRIB2, there is a unique paramId indicating the parameter and type of statistical processing, e.g., paramId=237167, shortName=max_2t for maximum temperature at 2 metres. A separate key, called statisticalwindow, is then used to specify the time window. For example, paramId=23167237167, statisticalwindow=3h identifies maximum temperature at 2 metres during the last 3 hours.
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