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Users often need to write their retrieved fields to multiple target files named according to forecast base-time, forecast step, parameter name etc. Rather than using an external loop around the MARS request this can best be done by using the multi-target feature, see Data storage keywords. If, using this method, you don't get the desired file names, they can in most cases be easily renamed afterwards.
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Observations are archived in MARS with 2 days delay. As a rule of thumb, you can always access date = -3, as the time at which observations archiving is carried out may vary from day to day depending on suite schedule. Please also note that observations are not generally accessible.
How can I compute the accumulation using data from the overlap stream?
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