Model output discussion - The run up to Christmas

[Scott Ingham]

14 minutes ago, Optimus Prime said:

On closer inspection we have this;

That looks very cold to me. Not far off early January 2010.

Looks like some special weather is on the way. Makes a change. 

Yes. 

Will come as a shock i don't see max temps above 3 celcius from the 28th

[clark3r]

I’m sure up north will do well out of this, down south I’m still not convinced, hoping to get at least 1 snow event down south even if it is a rain to snow event me thinking this will be anytime between 29 dec - 04 jan, hoping to see the low head further south east on future runs

[blizzard81]

The only thing I have learnt these past few days on this forum is just how difficult it is to please some people. I could understand it if we had experienced anything remotely wintry during mid winter over the last decade but we haven't. Even the last time it happened (winters 09/10 & Dec 10) was the first time in about 15 years. We should all be over the moon with what the models are showing right now for the UK. Too many on here are over analysing. Just enjoy and watch. Everything else will fall into place with these types of winter synoptics. Just a little more patience required. We've waited 10 years so another few days won't harm lol. It may be another 15 years before we see the likes of this again so sit back, stress less and enjoy the outcome which I suspect will be a happy, snowy one for most

[Cheshire Freeze]

3 minutes ago, fromey said:

That’s 2mtr temps

No, the chart was showing 'Taupunkt' which is German for dewpoint.

Won't even see sleet with dews of 2-3. Damn I knew this was all very marginal but didn't realise other factors such as DP were so far on the wrong side!

[Vikos]

3 minutes ago, booferking said:

If your talking about Germany and that particular run from ecm your right to be frustrated as your not even in -4 category your bathing in +2 to +4 for the majority of it, while uk sits in the coldest uppers the whole run so understand your frustration nightmare run for @jules216 also.

Sorry mate, but the conditions in Germany for snow are evem better then for the UK

But thats not my point...

[Scott Ingham]

13 minutes ago, feb1991blizzard said:

Really!!!!  -   Dew points above freezing from Manchester Southwards.

The extremeley low heights and low solar input at this time of year.

If it was end of jan or february damp squib but you'll be surprised how cold it can get in this set up end of December.

In all fairness thought weve not had many cold end of December for it to be fresh in the memory

[Downburst]

Looks like my canary date palms will need to be wrapped up, oh well

[Stu_London]

15 minutes ago, chionomaniac said:

Anyone else think that the ECM is a confused synoptic mess by day 10 this evening?  I do. It looks like it is getting signals from everywhere and can’t make head or tail of them!

Hi Chio

As I sure you will agree standard fayre when a SSW is in the offing. Would expect the GFS long ensembles which of late have been as tight as I have ever seen them, to go completely haywire with huge spreads in the next few days.

In the meantime, whilst I don't buy a significant snow event between Christmas and New Year (unless there are some unexpected upgrades), the period just after is looking very interesting and a disruptive snow event might be in the offing early in the new year, even before the strat effects well down.

[I remember Atlantic 252]

3 minutes ago, Scott Ingham said:

Yes. 

Will come as a shock i don't see max temps above 3 celcius from the 28th

if that's dew points, then it's unbelievable! cannot snaw with dp above 0

[feb1991blizzard]

1 minute ago, Scott Ingham said:

The extremeley low heights and low solar input at this time of year.

If it was end of jan or february damp squib but you'll be surprised how cold it can get in this set up end of December.

In all fairness thought weve not had many cold end of December for it to be fresh in the memory

It won't snow with Dew points several c above freezing.

[kold weather]

5 minutes ago, Vikos said:

So which is then? 2m temps? Snow at +5°C? Serious?

But it doesn't show 5C?

Most of those are showing 2-4c during the time period where any frontal system would come through. 

AND I'd never use the ensembles for an accurate representation of the temperatures in this sort of set-up as the resolution of the model ensembles won't accurately resolve the temperatures under evaporative cooling, something the models struggle with on both sides of the divide.

 

[Jason T]

I have not posted in here for a long while due to a medical condition now slowly under control. However I am struggling to see what the dissatisfied issue is with some..right now we are are seeing, if I am correct some of the best, infact tastiest output in a very long while..we are literally just walking through the start of meteorological winter..good timing, definitely!. Epic post by snow king..and the likes of Scott and some others all telling what's very very possible. It's been an unprecedented year all-round and understandably emotions are high, let's enjoy this lovely output. It's only just started...once I get back into the swing of things I can post more with charts..and data. Enjoy.!!! 

[booferking]

1 minute ago, Vikos said:

Sorry mate, but the conditions in Germany for snow are evem better then for the UK

But thats not my point...

Then you can rejoice snowed in.

[Cheshire Freeze]

I cannot fathom how we can have such a synoptic pattern as shown, just after the shortest day and yet have so little cold upper air around.

The more I look at it, think about it, the more puzzling it becomes.

Edited December 22, 2020 by CreweCold

[Optimus Prime]

5 minutes ago, feb1991blizzard said:

Its not, its 2m Dew points.

Yep. Looked at a number of the charts and didn't realise I hadn't clicked back to the 2M;

 

 

[Scott Ingham]

2 minutes ago, I remember Atlantic 252 said:

if that's dew points, then it's unbelievable! cannot snaw with dp above 0

Just realised with translation yeah. No chance with them dew points but Northern England and Scotland in the game. Still wont know surface DP's though till within 48 hours

[I remember Atlantic 252]

1 minute ago, CreweCold said:

I cannot fathom how we can have such a synoptic pattern has shown, just after the shortest day and yet have so little cold upper air around.

The more I look at it, think about it, the more puzzling it becomes.

because low is too far west? no N'ly or E'ly being modeled, air and 850's will turn quite mild late on Xmas Day, low coming down on 27th is too far west and north

[northwestsnow]

6 minutes ago, CreweCold said:

No, the chart was showing 'Taupunkt' which is German for dewpoint.

Won't even see sleet with dews of 2-3. Damn I knew this was all very marginal but didn't realise other factors such as DP were so far on the wrong side!

EC will be a mild outlier, I hope. 

[Vikos]

7 minutes ago, kold weather said:

But it doesn't show 5C?

Most of those are showing 2-4c during the time period where any frontal system would come through. 

AND I'd never use the ensembles for an accurate representation of the temperatures in this sort of set-up as the resolution of the model ensembles won't accurately resolve the temperatures under evaporative cooling, something the models struggle with on both sides of the divide.

 

At least for Germany, you can always add at least +2 to +3°C on top of that 2m temps output. See the dewpoints at this time, they tend to be positive, too, too much moisture in that airmass, too much mixing, too dynamic under that low.

Edited December 22, 2020 by Vikos
+ 2x o

[Scott Ingham]

4 minutes ago, feb1991blizzard said:

It won't snow with Dew points several c above freezing.

Just realised it DPs yeah no chance unless your in northern england upwards. 

We wont know these till 48 hours out however 

I dont see in that set up how they can be possible so i think once we get to the reliable these will change 

[Methuselah]

10 minutes ago, markw2680 said:

To many folk are panicking about will it be cold enough etc etc, the charts we are seeing for in a few days time are so rare we need to just enjoy what’s about to happen, there will be many surprises to come I’d think, let’s just get the cold low pressure in and relax and see what falls from the sky. Put it this way I think many on here will be keeping them curtains open a touch just to catch a glimpse of the local lamppost 

Who's 'panicking'? If it snows, it snows; if it doesn't, it doesn't... Unless of course, we on here, can generate so much hot air, it all turns to rain!

[Cheshire Freeze]

1 minute ago, I remember Atlantic 252 said:

because low is too far west? no N'ly or E'ly being modeled, air and 850's will turn quite mild late on Xmas Day, low coming down on 27th is too far west and north

Given the low drops from Greenland, you'd expect more cold in its circulation than what is shown. You'd think it was travelling over a lava bed the way those 850s warm up.

[Stu_London]

5 minutes ago, CreweCold said:

I cannot fathom how we can have such a synoptic pattern as shown, just after the shortest day and yet have so little cold upper air around.

The more I look at it, think about it, the more puzzling it becomes.

been a struggle to get any cold air in Europe this autumn to be fair

[Jason M]

1 minute ago, CreweCold said:

I cannot fathom how we can have such a synoptic pattern as shown, just after the shortest day and yet have so little cold upper air around.

The more I look at it, think about it, the more puzzling it becomes.

Its the squeeze between the Russian high and the low. It just pumps the warm air up into NW Europe. Comes back to the 'airmass' point I made yesterday. Effectively were sucking in a rTC airmass (returning tropical continental) around a closed off low. That Russian high has been a killer for recent winters as it just pumps warmth north and leaves us with no cold pool. Then add on 1.5c of background AGW and its a one way ticket to Mildsville (bit OTT but you get my point!).

Don't know about 'follow the yellow brick road' its a case of 'follow the isobars'.

[I remember Atlantic 252]

SW'lys before system arrives the problem?