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(b) The production schedule of the Met Office forecasting system doesn't prescribe how to build an ensemble for a specific nominal start date. The following choices are currently in use for the C3S products based on GloSea5 data:
FORECASTS: the most recent 50 members starting on or before the 1st of the month. (NOTE: The data from all the daily members, and not just those 50 used to produce the C3S forecast products, is processed and made available through the CDS)
HINDCASTS: 28 members (7 starting on the 1st of the month and 7 on each of the 9th,17th and 25th of the previous month)
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