The temporal aggregation is presented in two different formats: 6-hourly intervals and daily intervals. In addition, an aggregation based on a 5-day moving average (Alert) is also available.
4.1.6-hourlyAnchor Section4.1 Section4.1
The 6-hourly intervals are centred on the main synoptic hours (00, 06, 12 and 18 UTC) as described in Table 8.
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6-hourly interval | Observation time (t) |
00 | 21 UTC ≤ t < 03 UTC |
06 | 03 UTC ≤ t < 09 UTC |
12 | 09 UTC ≤ t < 15 UTC |
18 | 15 UTC ≤ t < 21 UTC |
4.2.DailyAnchor Section4.2 Section4.2
The daily aggregation refers to the union of the four 6-hourly intervals as defined in Table 8, therefore is the 24-hour period within the interval 21 UTC ≤ t < 21 UTC, where t is the observation time and the lower “21UTC” limit is the day before.
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