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An time anomaly in 'Average and Extremes 2010' view

Posted: Sun 25 Apr 2010 9:15 am
by Repairman77
Hi Steve,

I was puzzled to see at 9.30am BST this morning the max temp for this year of 17.1 when yesterday's 19.1 was the highest for 2010.

I checked the set-up page for Cumulus and the roll-over for data is set at 9am.
I figured that this was due to an anomaly between British Summer Time and Greenwich Mean Time.

At 10am the figures showed correct on the 'Average and Extremes' page which would perhaps indicate that although the Main Cumulus page gets it's time from the computer clock or WH1080 display, the data is coming from Greenwich Mean Time somewhere.

I don't think it's from the WH1080 display as that has the British Summer Time correct as it's the Radio Controlled version.

No problem but just interested in what's happening.

Mike.

P.S. Just noticed that Steve is away this week; anyone else any ideas?

Re: An time anomaly in 'Average and Extremes 2010' view

Posted: Sun 25 Apr 2010 11:34 am
by steve
The UK Met Office standard for the end of the meteorological day is 0900 UTC, year round. So if you select the 0900 rollover, by default it happens at 1000 BST in summer. The 'use 10am in summer' setting, which defaults to 'on', controls this (the option to turn this off exists because apparently some countries use 0900 local all year round, even during daylight saving time).

Re: An time anomaly in 'Average and Extremes 2010' view

Posted: Sun 25 Apr 2010 3:19 pm
by Repairman77
steve wrote:The UK Met Office standard for the end of the meteorological day is 0900 UTC, year round. So if you select the 0900 rollover, by default it happens at 1000 BST in summer. The 'use 10am in summer' setting, which defaults to 'on', controls this (the option to turn this off exists because apparently some countries use 0900 local all year round, even during daylight saving time).
Thanks Steve; I knew there had to be a logical explanation for it; fully understood now.

Mike.