Met charts - why is 12 UTC Sun repeated 3 times?

[Thresher]

Hi all

Can anyone explain the following to me?
If you look at the following link
http://meteonet.nl/aktueel/brackall.htm
link (I hope)
The charts are all at 12 hour intervals but the titles on the charts do not reflect this ie
12 18 UTC Thu 30 Nov
24 12 UTC Fri
36 00 UTC Sat
48 12 UTC Sat
60 00 UTC Sun
72 12 UTC Sun
84 12 UTC Sun
96 12 UTC Sun
108 12 UTC Mon

12 UTC Sun occurs 3 times, not a mistake, it is something I have seen often but not understood. Can anyone explain how it works?

Thanks

Brendan.

 

[TheBoatman]

Brendan
The left column is the number of hours + from the start 1800 UTC Thurs but by the time they get to Sunday they have made 3 predictions for that day because of the low pressure area with an occluded front which could either be in the Irish Sea or crossed the UK on Sunday to be in the North Sea.

What they are saying is they don't really know but have predicted the following on the charts - take a squiz at the Sunday charts and check the progress of the LP area.

Peter.

 

[Shanty]

Peter

Not convinced, I'm afraid. If your explaination were accurate, surely the hours elapsed would be the same for the three charts?

Having said that, I've no idea what the true story is. I'm inclined to the view that somebody keeps forgetting to update the header - just a guess

Tim

 

[BrendanS]

someone, or an automated system, has screwed up.

 

[salamicollie]

Its always screwed up - everyday the sequence goes wrong on the day, just look at the hours!

 

[savageseadog]

Perhaps a meteo expert could also explain why on Tuesday the isobars show a clear North or North East airflow and XCweather shows the opposite.

 

[jimg]

I am glad you said that! I agree it is never right and you have to work it out for yourself.

 

[ParaHandy]

These sites FTP the data from the MET office. The MET office issues T+0 to T+84 at or around 0730 and you can get them from here so these are all timeously produced. Then, during the day, the T+96, 108, 120 & 132 are sequentially issued. So, at some point during the day, you'll get some overlap with charts produced previous day and could have T+96 & T+102 or even T+120 giving a forecast for the same time ... logically, the MET ought to update all charts at the same time but they don't. Whether true or not, I was told that the forecasts up to T+84 come off one program which is an amalgam of the EU forecasts and their own efforts and the later, longer range, ones comes entirely from their own efforts and via a different weather forecast programme ...

 

[TheBoatman]

I've just had another squiz at the site and they've changed the timings for Sunday it now reads 00 - 12- 24 UTC

Such is life

Peter.

 

[JEG]

What is UTC?

Thank you


John G

 

[RobBrown]

Coordinated Universal Time- a universal World Time system tied to atomic clocks.

For here in UK I think of it as GMT /forums/images/graemlins/smile.gif

 

[TheBoatman]

[ QUOTE ]
Coordinated Universal Time

[/ QUOTE ]

Isn't that C.U.T?

Actually this has raised a question in my mind because I always thought it was co-ordinate and not co-ordinated - Universal Time Co-ordinate.

Not that I'm really worried because I'm a strictly GMT man myself.

Peter.

 

[peteandthira]

Interesting article 'ere (for some, anyway!)

http://en.wikipedia.org/wiki/Coordinated_Universal_Time

Further education can be provided by following some of the links within the article.

Pops