Winter Model Discussion - 12/01/13 06z Onwards

[lindy2017]

I couldn't have put it better myself! I am quite astounded at the negativity on here. We have a week long cold spell to look forward to which given we were forecast to be in a mobile westerly by Tuesday only 2/3 days ago is a wonderful scenario (and rare) for the UK.

I don't understand what people are after? We always get told 'get the cold in first and the snow will follow'. Yes some of us may get more than others and yes an unlucky few may get none at all, but given the present outlook (a very cold and somewhat unsettled theme) things don't really get much better than this for the UK in winter.

A little perspective required methinks...

We have cold snowing now .........im happy.....

[mountain shadow]

I am happy with the fact that the model runs extend the length of cold by 12hrs every 12hrs........ long may that continue.

This was exactly my observation.

ECM bigged up that it will be right despite the fact it keeps delaying the return of the Atlantic. Perhaps an indication that Its upstream modeling is not to be trusted

[Froze were the Days]

looks pretty certain we are going to get some influence from the Atlantic late in the week/early next week and the form horse is probably with the ECM (which hasn't changed at all with the link to the Azores high) and the GFS. UKMO and GEM have been in the same boat for the last day and the HP gives more amplification out west and the possibility of undercutting.

Saying that read the odd post saying that this 12z run is really poor but it's no worse than the 0z and it does give us some opportunity with a weak trough trying to go southwards but most of the energy is to the north, even at the end of the run is far from certain so some hope.

[chris55]

Whatever we end up with, the inability for the Atlantic to break through is becoming a consistent trend. EC seems to be reducing the Eastward progression of the Atlantic with every run, UKMO is consistently throwing the depressions under the block, and GFS is somewhere in between. GEM is similar to UKMO.

My summary, UKMO/GEM are more likely to be on the money.

[If Wishes made Weather]

Just noticed that the updated T72 fax (sorry cannot copy) shows the mdd Atlantic small low that eventually develops into the SW that undercuts, so it would seem that they are reasonably confident of the computer generation up to that point.

[nick sussex]

This is the latest fax chart for T72hrs:

Gone is the strong ene flow to be replaced by a slack flow with less cold uppers!

Probably still cold enough for snow showers but at the moment unlikely to get far inland.

For those in London however a chance of a Thames streamer depending on the exact direction. Given the volatility in the models this fax chart is likely to change so the flow might be increased in future ones.

[danm]

Yes, the METO are now confident of a cold block right into next weekend with cold uppers really digging in. Snow showers moving inland from those North Sea troughs and really pepping up by Wednesday.Anyone disappointed by the lack of any white stuff in our area tomorrow should see some by the middle of the week and feeling bitter in a keen NE flow!

This is the updated fax chart for Wednesday:

Not as good as the previous chart unfortunately.

[Jezzer]

I couldn't have put it better myself! I am quite astounded at the negativity on here. We have a week long cold spell to look forward to which given we were forecast to be in a mobile westerly by Tuesday only 2/3 days ago is a wonderful scenario (and rare) for the UK.

I don't understand what people are after? We always get told 'get the cold in first and the snow will follow'. Yes some of us may get more than others and yes an unlucky few may get none at all, but given the present outlook (a very cold and somewhat unsettled theme) things don't really get much better than this for the UK in winter.

A little perspective required methinks...

Yep, I'm always amazed at how when we have cold on our doorstep and set to stay for a week people are still downbeat. A bit like complaining about a lack of buses only to discover three have past without you noticing. I'm loving the current synoptics and associated model watching and the fact that we've just started a cold spell makes it all the more satisfying.

Compared to December this is wonderful! UKMO has been so consistent I'm not sure anyone can doubt it at the moment imho

Edited January 13, 2013 by Jezzer

[phil nw.]

Anyone notice the cold breakdown keeps getting put back beyond 5 days?That should tell us something about model consistency at the moment.

They are dealing with the age old difficulty of the cold and mild air boundary and where disruption will occur, complicated by a weaker than normal jet and a stubborn block to the north east.

I am content to see uppers around -6 to -8C across the country by midweek.

http://www.meteociel...CH0-96.GIF?13-0

No point in fretting about snow details too far ahead-take it day to day.

Certainly beyond T96 there will be continual changes in detail but with the block still resisting the Atlantic at T144hrs.

http://www.wetterzen...cs/Recm1441.gif

http://www.wetterzen...s/Rtavn1441.png

http://www.wetterzen...cs/Rukm1441.gif

At least the cold is here for this week at least.

The UKMO is a cracker for a serious snow event btw but even if it`s toned down i would suggest there`s plenty in the models tonight for cold fans to be optimistic about.Snow events in a cold block that lasts a while can often pop up at short notice.

[nick sussex]

Just noticed that the updated T72 fax (sorry cannot copy) shows the mdd Atlantic small low that eventually develops into the SW that undercuts, so it would seem that they are reasonably confident of the computer generation up to that point.

Lol! You mean how they were confident of that strong ene flow which evaporated in 12hrs on the fax chart.

If the UKMO cant get it right at T72hrs then my confidence in any output past that point is the lowest its been since I've been a member in here.

Sometimes you just have to accept that the models are going through a bad patch and change your expectations accordingly.

In the UK detail is really important and thats hard to come by at the moment past 72hrs.

[Frosty.]

This is the latest fax chart for T72hrs:

Gone is the strong ene flow to be replaced by a slack flow with less cold uppers!

Probably still cold enough for snow showers but at the moment unlikely to get far inland.

Seems strange that, the latest 3-5 day meto update mentions turning windier in that period the fax chart covers, with wintry showers blown in from the north sea, and that update was only issued around 4 hours ago.

[johnholmes]

Shame they couldn't bother putting together a forecast that had the latest data, looking at the SLP charts thats using the 00hrs run data, maybe the UKMO didn't expect such a change in the 12hrs but it's really one of my irritations, I've seen this happen before even on evening forecasts where the datas already been superceded.

Your comment amuses me Nick. Have you the foggiest idea what it is like in a rapidly changing situation in the Exeter forecast room. I am sure Ian F can explain the current set up but I remember when this kind of situation occurred and trying to get hold of the duty BBC forecaster with no phone in the studio is not easy nor is there likely to be time between deciding to issue a new Fax chart and grabbing hold of him before he/she disappears either into the newsroom or the studio. Give em a chance mate.

[nick sussex]

Well its basically when you get a favourable ene flow with cold uppers, because of the estuary and surrounding topography this developes precip in the estuary which edges west into London.

So in this case it does look cold enough for snow but its just a chance at the moment.

[ANYWEATHER]

I think the models are now shaping up to show us that the cold spell carries on for a good while even though the Atlantic tries to push in It looks interesting at the end of the week in terms of snowfall ,battleground situation,anyway looking forward to some old archive type weather coming up

[Bristawl Si]

Lol! You mean how they were confident of that strong ene flow which evaporated in 12hrs on the fax chart.

If the UKMO cant get it right at T72hrs then my confidence in any output past that point is the lowest its been since I've been a member in here.

Sometimes you just have to accept that the models are going through a bad patch and change your expectations accordingly.

In the UK detail is really important and thats hard to come by at the moment past 72hrs.

Not just the models "going through a bad patch" - from my viewing point i think the human input from the forecasters is struggling at the mo.

It's only 2 hours ago i saw a forecast on tv showing a reasonable strong easterly flow for midweek - latest fax shows a fairly slack flow, as you say.

[weather eater]

Some of you appear to be determined to look too far ahead and get downbeat about what you find there, the last week of model output should have taught you the futility of that approach. I can only surmise that you teachers at school must have found you pretty hard work. I hope you didn’t go to school when I did, as a knuckle wrap on the head was never pleasant and there was always the prospect of the blackboard ruler or flying lumps of chalk. Yet again while its not perfect the ECM appears to be going in the right direction, however viewing outputs is going to continue to be hard work as the level of uncertainty continues.

[blizzard81]

Your comment amuses me Nick. Have you the foggiest idea what it is like in a rapidly changing situation in the Exeter forecast room. I am sure Ian F can explain the current set up but I remember when this kind of situation occurred and trying to get hold of the duty BBC forecaster with no phone in the studio is not easy nor is there likely to be time between deciding to issue a new Fax chart and grabbing hold of him before he/she disappears either into the newsroom or the studio. Give em a chance mate.

Hi John, hope you don't mind me jumping in here. This is why I mentioned earlier that maybe the forecast should be aired later so that they

have time to digest the 12z suite. Surely we can manage that in this day and age.

[Paul]

Can we move away from TV forecasts and back to the models please - there are threads available to discuss countryfile etc

[Iceni]

just about to watch the Day After Tomorrow yet again.....wistfuly remembering how, only a few days ago, the models had me dreaming it could be like that this week

People are totally misled by news footage of the two winters of '47 and '62/63… I think they expect it was a full on Day After Tomorrow blizzard every day, well it wasn't. It just stayed cold enough for whatever snow had fallen to gradually accumulate. There were plenty of days when temps rose enough to melt the top layers, which would refreeze a couple of nights later.

Big motorway gritters didn't exist, at best they were a couple of blokes on the back of a lorry shovelling it onto the road, more often a heap of sand beside hills (which were useless as they got covered up and you couldn't see where they were). And people didn't even have front-wheel drive, we had to pile into the back seat to weight the car onto those back tyres for grip or we fitted snow chains which mullered tyres after a week or two.

What we are about to receive may turn out to be special and long lasting as those winters, or not, but people must be a little more realistic.

[ChartViewer]

CMA T72

850'S T72

CMA not seeing any jet energy east but more southerly tracking at T72.....We will see

Edited January 13, 2013 by ChartViewer

[Col Berkshire]

CMA T72

850'S T72

CMA not seeing any jet energy east but more southerly tracking at T72.....We will see

How has this model been performing? To me it seems fairly consistent.

[ChartViewer]

How has this model been performing? To me it seems fairly consistent.

Certainly is not one the peanut brigade described by NOAA today

[EML Network]

WOW !! just about sums tomorrow up, what a mess !!

[pages]

CMA T72

850'S T72

CMA not seeing any jet energy east but more southerly tracking at T72.....We will see

Very strange at t72 20mb higher heights over Greenland, scandie high further north and west than any other model.

Only way is into the freezer.

How can it be so different at T72?

[Mac_SE]

Am I right in thinking in that the current setup (SSW), the models are currently overcooking all possible scenarios (jet stream and snow potential particularly) out to +72 and any ideas if this is particularly due to it? The carrots they dangle are mostly and frustratingly always delicious (from a cold perspective), but continually appear to get toned down as we get into the reliable timeframe.