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Table 8 - Definition of the 6-hourly aggregation intervals. The defined time limits (note that 21UTC in the 00 interval refers to the previous day) are applied to the observation time (t) as specified in the NWP monitoring reports. It should be noticed noted that only the observations that were made available in time for each of the NWP assimilation systems are supposed to be included in the NWP reports.
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