Tamara, I would certainly agree with what is being said in principle, but what should happen and what actually happend may be two different things for whatever reason.
Not seen GP posting over on NW, I take that to mean he has no confidence in the cold evolution.
His thoughts are always valuable to read. In terms of reading between the lines of the erratic modelling suites and taking them with a pinch of salt, it seems to me that his most recent opinion and guidance is moving along quite well in terms of the way the pattern is heading, and most especially in terms of how and why the pattern from the first half of the winter is already completely different. That is important to bear in mind imo in terms of any model suggestions to default back to that previous pattern
More warming forecast which is good news for cold.
http://176.31.229.228/modeles/gfs/run/gfsnh-10-240.png?12
http://176.31.229.228/modeles/gfs/run/gfsnh-10-300.png?12
http://176.31.229.228/modeles/gfs/run/gfsnh-10-360.png?12
Yes, thats the latest MT showing up. ECM should also pick this up quite soon too
Looks like a significant warming event will happen mid feb. Could lead to cold later in the month
According to what's shown here, http://wekuw.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ts.php a stratospheric warming occured 2 weeks ago. Do you think that this is what has lead to the blocking pattern that we see just north-east of Scandinavia now?
Its one of the main factors yes without doubt
Certainly struck by:
- Warming in the stratosphere for January started being forecast before Christmas.
- These forecasts succesfully predicted a series of warming events.
- These were followed by disruption of the polar vortex from mid January.
- Which eventualy lead to much colder weather across most of Europe by the start of February.
Wouldn't want to go out on a limb and say this definitively made the case one way or another (plenty of other factors, coincidental or causal etc, etc,), but I found it interesting to watch none the less.
That's a good article, thanks for posting that.
I've got a long way to go, but that has cleared up some points I didn't understand.
Cheers
Certainly looks like a huge warming event is going to happen soon and this must increase the chance of a very cold end of Feb early March.
It's interesting but what i don't get is that continental cold air is a surface feature so I don't see how it's brought about here by 'burrowing' down of easterlies from higher up. Further, and as I understand it, there is little interaction between the top of the troposphere and the layers above - hence the tropopause. Perhaps is just a question of what is going on not being very well explained....
[quote=Steam Fog;292991]I suspect this was posted somewhere in amongst the media thread, but it's relevant here as well (and may not get so quickly buried). http://metofficenews.wordpress.com/2012/02/09/whats-bringing-the-cold-weather-to-europe-and-the-uk/[/quote]
The thing is, that there have been very ordinary humble non professional members of the public who are simply weather enthusiasts on internet boards such as this one and its neighbour board, that made this connection a few years ago, researched it, and started using it in longer term forecasting waaay before the METO did. Its not long ago they were doing seasonal forecasts based on supposition of NAO signatures 6 months ahead in the atlantic ...oh and continuing to mix climate and weather through an irresistable need to bring multi decadal AGW theory into it as well
No coincidence that their extended forecasts have, relatively speaking, improved.
They got badly burned when evidence emphatically showed (the obvious)that HLB for the short season was still possible in the winter of 09/10. I remember a spokesperson from ECMWF interviewed on a Beeb biased AGW programme around 2007 who suggested that winter time HLB was something left back in 1962/63 and made its last dying imprints in the late 70's and 80's. That to me proved that they were using AGW theory rather than looking at cyclical natural forcing patterns such as stratospheric cold/ warm phases as attributed to QBO patterns, ozone, PDO jet stream cycles etc.
In fairness to the METO, what they have written in this link is absolutely correct and very well explained My point is that they have changed their tune for the better, unfortunately because the weather(not the climate) got the better of them
Edited by user 10 February 2012 23:06:09(UTC) | Reason: Not specified
That question has been responded to in the article - follow the link.
If I understand it correctly the wind reversal in the stratosphere permeates down and inhibits the jet (weakening and/or deflecting it). This allows high pressure cells to form and hold position.
As they say, even they're not sure of the process.
Indeed - but I suspect their error was in placing too much emphasis on AGW effects and not enough on the natural cycles to which you refer. I still think over time that the AGW signature will have an effect but it's difficult to work out regional impacts because of the complex interactions. In the meantime let's make the most of HLBs while they are manifesting themselves.
^
Good discussion but for the casual reader & the not so geeky, the last few posts probably sound like riddle-speak.
Anyway, as 'HLB' is not something you can go google and it's a TLA (three letter acronym) for a term I had to work out from the context of the discussion above, it's probably worth making clear that 'HLB' probably = 'High Latitude Block'.
Quite a convicing warming modelled in the stratosphere, albeit about 120 degrees west of the last one. Could that favour a block over Canada / Greenland this time ? Lets hope so because the Russian/Scandi one was all but useless up here.
I think there might be something in this SSW stuff, but I think it's only part of the mix and I think placing to much reliance on it as a forecasting tool will find those doing that coming unstuck at some point. I'll also say I'd rather not see this thread become another AGW/Met O bashing thread.
It's my impression. But, I'm rather new to all this, so, how much weight should we give SSW and the state of the Stratosphere as a predictor of weather lower down in the atmosphere?
Edited by user 12 February 2012 14:22:21(UTC) | Reason: Not specified