quote from aus AIP GEN3.5
-----------------------------------
20. SIGNIFICANT WEATHER CHARTS
...
20.3 The availability of the Australian area significant weather charts
and validity times are as follows:
Appropriate Availability Time (UTC) Validity Time (UTC)
0100 1800
0700 0000
1300 0600
1900 1200
20.4 Significant variations during the period validity time
plus or minus three hours
are included. Amendments between routine issues
are normally narrative advices of variations, but they may be
incorporated in a new chart.
-------------------------------------
about the WAFC london i only got this
http://www.metoffice.gov.uk/research...ar03/wafc.html
quote:
...In addition, the following charts will appear with the same header every six hours, with a validity time 13 1/2 hours later: PGAE06, PGCE06...
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i am not sure weather the chart only valid at the valid time like a snapshot...perhaps anyone could supply me with a reference. Thanks