Winter Model Discussion 18Z 19/1/13 onwards.

[mountain shadow]

There is no cold evident in the model output past Saturday, because the next potential cold spell is outside the model range, so yes SM and others are correct.

However, with a continued weak vortex, and more importantly a more favourable MJO becoming, colder weather may start to show its hand again over the weekend.

[WhiteFox]

Yes but we are talking well into FI i.e +384.

If we are relying on discussing charts at +384 then this just illustrates how poor the output is prior to this!

I think that t+384 actually overshoots the runway of Fantasy Island and ends up ploughing into the sea at the far end! Anyway, it's back to spotting trends on ensembles now. Often trends won't be picked up until 7 days in advance as the actual outcome of solutions has such a big impact on events further down the line. We'll see.

[No Balls Like Snow Balls]

Yes but we are talking well into FI i.e +384.

If we are relying on discussing charts at +384 then this just illustrates how poor the output is prior to this!

A lot of people seem to change the reliable time frame as much as they change there under pants. All of a sudden T144 to T240 is reliable where as this time last week it was in the depths of FI.

[Yarmy]

Apropos of nothing.

1. The London GEFS ensemble mean is almost bang on the 30 year average (as per Gavin's post that everyone ignored).

2. By this weekend I will have had -as will many others- nearly 2 weeks of thick laying snow and a few double-digit minus temp nights.

3. Verification Stats (real numbers, not anecdotal 'such and such model is rubbish') show that the major players on average hover around 0.9 for 5 days and 0.8 for 6 days. After that we can surmise they probably decline rapidly (UKMO don't even bother beyond 6 days). Still, 0.9 at 5 days is a staggering intellectual achievement and is improving every year. Lorenz famously suggested calculated 14 days as the limit beyond which (detailed) forecasts would be impossible. 6 days takes us to Jan 28.

4. February is usually the coldest month of the year.

Edited January 22, 2013 by Yarmy

[BLAST FROM THE PAST]

Come on Fred the signal is so strong for a return to mild SW,lys at +144. I would even say I have a greater chance of winning the Lotto than a sudden switch in the output at +144.

Dave

Model signal is strong, what else is strong?. What I'm saying is they may be right, they may be wrong. Either way I don't trust them at that range

BFTP

[Severe Siberian icy blast]

Well if we look at trends then the last 4 or so gfs charts have shown northerly winds in deep fi 300hrs or so , yes completely fi at the minute, but it's constantly shown , with the Atlantic blocked.

It also shows southwesterly winds before hand ! But for me the 4th feb is a bench mark

[Mark Neal.]

In regards to some ECM Ensembles with 26/51 going for a quieter and perhaps blocked atlantic, it may well be out in FI, but a pattern has to start from somewhere, some in here should opt for the glass half full approach, so many negative posts.. We aren't going to see snow for 4/5 weeks on end with cold temperatures there will be milder interludes, Greenland High by Mid February i reckon!

[Jonan92]

7th GFS run in a row showing the same

[Mark Neal.]

7th GFS run in a row showing the same

Exactly even though its right out in FI, it has been a trend in recent days to show a Northerly by +300 but consistent to try and build heights, i'm not saying this is right, as we now know how model output changes so close, let alone right out in 2 weeks time, but for now Trends are our friends! Keep the Faith

[Troubleatmill]

Final post for the morning.

To all those who are complaining about mine & Steve M negative posts this morning. Please could you post a chart from any model that suggests a return to cold between +144 to +240. Also try and find a chart that suggests any form of blocking to our N in the same time period.

Good luck!!

Like nothing better than a challenge

Unfortunately i came up a blank and agree that there aint much for the next fortnight (from the breakdown this weekend) to grasp onto for cold air to visit us again........according to model output from the 06z that is & 240 is the max for looking at new trends, anything beyond is really not worth spending time on, even if by some chance it does later move down to the 240+ time area, who here hand on heart does get excited by cold northerly toppler at t336?

Edited January 22, 2013 by Nick JB

[TEITS]

A lot of people seem to change the reliable time frame as much as they change there under pants. All of a sudden T144 to T240 is reliable where as this time last week it was in the depths of FI.

There is a world of difference between the models now and last week. For example we now have very good agreement amongst all the models and ensembles which cannot be said for last week.

Sorry but anyone expecting a significant change to a cold spell between +144 to +240 is in denial. Comments such as "I don't trust the models" is called hopecasting and trust me I know because I used to do it myself!

[bluearmy]

the gefs mean actually show the transfer of energy from newfoundland to scandi between the 4th and 6th of feb on the mean. whether thats the end of the energy is open to question but for whatever reason, the gfs seems keen to build ridging to the west/northwest around that timescale. i guess we just have to watch and be patient. its feasible that this could be brought forward but there is no evidence that this will happen. in the meantime, the winter will continue, wet,dry,cool.mild,average - its nothing unusual. wonder how much below av the cet will end up ?

[No Balls Like Snow Balls]

There is a world of difference between the models now and last week. For example we now have very good agreement amongst all the models and ensembles which cannot be said for last week.

Sorry but anyone expecting a significant change to a cold spell between +144 to +240 is in denial. Comments such as "I don't trust the models" is called hopecasting and trust me I know because I used to do it myself!

And the older we get the more grumpy and negative we become LOL - only Joking with you

[frosty ground]

26/51....

so then an exact 50% split-

you may have also say that 25 dont...... so based on that info there is no clear pattern...

S

But you (As you have in the past) would use the Ensemble mean in that situation thou! Even thou it’s about a useful a third party candidate in the presidential election in America! Clearly there has been a swing towards high pressure influence as the tweet suggest that was not there yesterday, hence while there is nothing concrete about any one outcome there is a greater possibility of high pressure influencing our weather!

[Catacol]

given how weak the vortex was even before the SSW occured it surprises me we are not seeing bigger effects.

The NH pattern shows that were ARE seeing big effects, but unfortunately even a weak vortex carries some strength, and it has decided it wants to holiday in the north atlantic rather than go somewhere else. It's put the towel down on the sun bed too.. and the siberian chunk now appears to be considering a holiday further east. It's the luck of the draw. Someone earlier posted that the stats on SSW events are nowhere near to universal cold. What they do is open the door to an extreme spell of weather: indeed GP even confidently touted that this was exactly what was going to happen when he posted such a few days ago... but if the vortex shards that are left enter the atlantic then really that must trump most other processes going on.

I'm trying to become interested in other aspects of the pattern now, and the one that is really interesting is to see how the MJO composites fair running up against this SSW induced pattern. They are surely separate processes in themselves that usually have in impact on their own, but with both tropical convection and growing angular momentum running alongside a cracked and displaced vortex we have the chance to see which is the biggest global driver. I wonder on the historical record how often a phase 7/8 in January/February has been combined with a positive NAO and a strong atlantic westerly? Would it be unique? At moments like this I dont have enough bookmarks in Chrome and need a few more hours to search for any archive that might exist.

Agree with anyone saying that of course winter is not over. Heck - its only Jan 22 and a lot can change, but something drastic needs to happen to the projected polar pattern in terms of vortex placement if we are going to see any joy soon.

Edited January 22, 2013 by Catacol_Highlander

[mike Meehan]

Looking at the fax charts, there seems to be a big jump between the 96 and the 120 and as far as I can make out the low which is on the sw tip of Greenland on the 96 suddenly ends up just to the nw of Scotland, while a euro high develops and is further north than what was shown on previous runs.

The temps in central/north Europe appear to be falling, so would this give encouragement to the high?

It seems to me as though the fat lady is still sitting down.

[Catacol]

in the meantime, the winter will continue, wet,dry,cool.mild,average - its nothing unusual. wonder how much below av the cet will end up ?

December came in bang on average. My feeling is that we are probably running marginally below average for January, but Phillip Eden's site doesnt seem to have been updated at all for January. Anyone have a site with the running total?

[That ECM]

Agreed the output from sat from a cold perspective is not great. If you can look at charts and then translate that into what it would actually give us should they be a true reflection of what will happen. However there are those who have the ability to look at other info and make an informed forecast. Meto longer term favour cold at the moment. GP and others also.

A poor analogy this maybe but it's a bit like someone saying that team a will beat team b. then team b going one nil up early and every five minuets someone saying the team you forecast to win are still losing. Not until the end will we know how things panned out.

To be quite frank, I am surprised GP and others share their thoughts if they then are constantly told their team are losing.

[Nick F]

Certainly no quick and easy route back to cold once the more mobile Atlantic comes back in this weekend. Low heights dominating to the N and NW and heights building over Europe a consistent signal from the models until the end of the month and perhaps continuing into the first week of Feb.

Though the Met Office seem to be hinting that colder weather will return again towards mid-Feb.

Just need to hang on in there until we see signs of the PV split once again.

Edited January 22, 2013 by Nick F

[Stu_London]

December came in bang on average. My feeling is that we are probably running marginally below average for January, but Phillip Eden's site doesnt seem to have been updated at all for January. Anyone have a site with the running total?

January looks likely to come in below average on all measures (61-90, 71-00, 81-10).

Also the period 12/01/13-21/01/13 is likely to be close to or below 0C for the mean. This is likely to be extended another 2-3 days at least.

There does appear to be a strong teleconnective signal for mid atlantic or greenland high, with lower heights transferring to scandi. This has been a feature of recent GFS operational runs in the +300 range, but it's got to start somewhere and the trend is you friend for now.

[MattH]

Morning all..

Wanted to post seeing some of my tweets from earlier have been mentioned on here and also it's a good time to highlight a few features of interest. As ever twitter is not the place for more in-depth discussion, it is a way to get a piece of information out, and as ever, 'you' take that information as you will. When I comment on the EC ENS I am simply putting what they show into text format, so again take them as you will.

In a way I think Steve M is correct, but perhaps not using as such a strong word as "denial", that the weather is and will change. The synoptic evolution of late clearly has been a case of lows attempting to come into the UK but being 'deflected' south or south-east into France. The reason for that is clear and it's been down to the block to the north-east and as someone rightly mentioned, you don't need a 1040mb parked to the NE to produce what we have had. However, the pattern has and will change and in a way ironically down to the SSW;

http://wekuw.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ec.php?alert=1&level=100&forecast=all&lng=eng#fig11

If you flick through those charts (100hPa), essentially the bottom of the strat/top of the trop, you will see that the strat images starts with that nuisance 'daughter low' over NE Canada which is a remnant low of the split of the vortex, but note to the N and NE of the UK there is a ridge, albeit minor, but it's there. However, if you follow that low whilst it does weaken it moves across the N Atlantic and becomes quite dominant whilst high pressure remains more influential on the Pacific side of the pole, that is the major change and that is why, on this occasion, the Atlantic lows will win out.

Now, looking at what we have had and we still have. By this Friday the colder weather across the UK will have been in place for essentially 2 weeks, so that's 2 weeks of January, pretty much half of the month and this still is the UK and not Canada. That, in my opinion, is a pretty noteworthy period of cold weather. As usual there will ALWAYS be some places of the UK that don't get as much snow as others, or don't get any at all, but that's the way it always goes, just like in summer when someone gets an impressive thunderstorm yet 30 miles away, nothing.

What I will go on to say is that this winter is shaping up to be one of quite significant extremes and I feel that trend will continue. Because of the state of the stratosphere I don't believe that once this unsettled spell sets in it will continue throughout February, not just because of the strat but for other reasons as well. I really do honestly believe, also in association with the EC32 as well, that a more blocked pattern will return, whether it's as extreme as some of the scenarios 'GP' has highlighted, perhaps not, but still colder weather does seem likely once again.

However and personally I believe these two weeks are likely to be the UK's "winter" mind. To get the longevity of this again and also the amount of snow through the middle and latter half of February will be a tough ask, clearly not impossible, but it'll be a tough ask. All in all, milder, wetter and windier yes for a time, but throughout the whole of February?...Not if you ask me.

Sometimes 'worrying' about what may or may not happen longer term is pointless because as we have seen the weather can change so quickly. Beginning of January we were coming out of a serious amount of flooding, not a frost in sight and now look what we have and still are having. I hope those who like cold weather have and continue to enjoy this weather simply because synoptically it has been impressive, no-one can say otherwise.

Regards, Matt.

[Timmytour]

I've really enjoyed this cold spell of weather...and while maybe the cold has not been that dramatic, nor the overall amount of snowfall, the time it has spent snowing is one I can find few winters to compare to, and i'm sure my kids will look back on it in year to come and remember it as a "real winter"

And strangely enough, I remember the approach of it gathering pace (though to be fair it seemed to take ages) with the kind of pessimistic comments that TEITS and SM are coming out with now!!!

i remember it so much because it was odd for me to feel an enthusiastic optimism for something which seemed to go at odds with what the both of them were saying...as I regard them as two of the most informative people on here.

This time i have more hope than optimisim. I don't buy into the "there's SSW so there must be cold" argument. But I am mindful that this latest episode arrived via a mild spell that did at one time seem set to last the winter through. So it can happen. It might happen. I hoep it will happen. But i don't think it will!

then again.....despite model agreement, i don't buy into the easy breakdown of this cold spell anyway....so what do i know??!!

Edited January 22, 2013 by Timmytour

[syed2878]

remove if needs be mods. It seems if any1 goes against the 80percent here then these people r shot down with flames. Over the last cuppall of days posts from eye in the sky and steave m has been quality and yet they were shot down by the 80percent because they not saying what most of us want to heare and yet nither of them or any1 said winter's over.

[frosty ground]

Looks like the GFS Control run bring high pressure over the UK from the east by 216 Hours.... It then starts to shift it towards Greenland..... A quick return to cold if that was the case! If the Atlantic is being overplayed then this is a real possibility beyond the breakdown this coming weekend!

[frosty ground]

Final post for the morning.

To all those who are complaining about mine & Steve M negative posts this morning. Please could you post a chart from any model that suggests a return to cold between +144 to +240. Also try and find a chart that suggests any form of blocking to our N in the same time period.

Good luck!!

http://modeles.meteociel.fr/modeles/gens/run/gens-0-1-216.png?6

GFS 06z Control Run......... This leads to Cold! Do I win anything