Model Output Discussion - Into Winter

[carinthian]

42 minutes ago, carinthian said:

Morning , looks like this mornings runs show little respect to the entrenched cold to the North East. After several attempts The Atlantic makes in roads across most of the British Isles by the end of next week at 168T. The GEM model shows the greatest resistance and the UKMO again the most progressive to flush out the cold. Just waiting on ECM  run.  I would think period 120-144 T  still remains problematical regarding the medium term outlook. Whether the waft of mildest is temporary we wait on or not at all !

C

Looks like latest ECM run joins UKMO to flush out the cold sometime next week. I still think ( 120T-144T) remains a period of uncertainty. Currently we have 60% snow cover across Europe at the end of November. That extensive amount has not been seen for quite sometime for so early in the season. So for the next 5 days the cold remains entrenched for quite a big part of Europe /British Isles and the snow cover looks like it could even grow further..Henceforth, the flush out of cold could be delayed if the Atlantic underestimates' the block of cold air but that currently appears not to be influencing the current medium term runs. We wait and see if the flip occurs .

C

Edited December 1, 2023 by carinthian

[KTtom]

Not sure the implecations further down the line on the TPV but thats some serious WAA for western europe. Scandi countries seeing an increase in temps of 20 odd degrees in 48hrs according to ecm, which, is slightly different to last nights offering.

[IDO]

We need a few more runs before we dismiss last night's ECM 12z, as the GFS control also showing similar this morning:

I assume it depends on the upstream Pacific wave killing the jetstream that has powered up over the weekend to push through the westerly flow. The GEFS mean highlights this, with the upstream ridge cutting off the flow of the tPV on its travels to our NW, so on this run, the tPV is split:

So, there will probably be a period of model uncertainty as we await specifics as to whether we get an early second shot.

[Dennis]

Morning GEFS

good to see what the MJO could do next phases in DEC23

[saintkip]

33 minutes ago, Ali1977 said:

Still looking good for central southern England the the midlands Saturday night - maybe a surprise for some when they wake up Sunday, albeit it’ll be melting pretty quickly!! 

No offence old chap but I’m not sure central southern England is looking good unless it’s rain we want.

[SLEETY]

00z runs always poor for some reason, hopefully the 12, runs show similar to yesterday's. 

Can't bare the thought of milder weather and relentless   rain again

Edited December 1, 2023 by SLEETY

[TSNWK]

22 minutes ago, Dennis said:

Morning GEFS

good to see what the MJO could do next phases in DEC23

Are only hope it appears this morning...heres hoping for a day of improving runs. 

Off to South East thread for blob watch.  Brewing on Thames estuary 

[tight isobar]

It’s not to difficult to note this possibility of a downwards trend on the ens.. the ec are short atm but the American model ones are also on a similar page. 1 gets the feeling todays outs, will be quite telling.in regards to mid December .

[Chertseystreamer79]

Same old morning runs...

That depth of cold is gonna prove a problem for any model to break down. Happy advent! 

[Cambrian]

It’s going down to the wire!

The block holds the centre of the incoming low offshore at day 3. It forces it to phase through the UK and Ireland, providing an easterly flow in front of it, rather than a southerly. ECM op.

Yesterday’s 0z at 96h vs. today’s 0z at 72h

 
 
 
 

Striking differences at such close range, uppers stay subzero, markedly less northern encroachment of the milder air. Thoroughly fascinating to watch this!

Edited December 1, 2023 by Cambrian

[nick sussex]

The last week has highlighted the inability of the models to deal with shortwaves .

The ECM mean shows good support for the shallower low further south .

The UKMO fax charts look like old news already .

[TauntonRoss]

Here we go again...

[John88B]

10 minutes ago, Cambrian said:

It’s going down to the wire!

The block holds the centre of the incoming low offshore at day 3. It forces it to phase through the UK and Ireland, providing an easterly flow in front of it, rather than a southerly. ECM op.

Yesterday’s 0z at 96h vs. today’s 0z at 72h

 
 
 
 

Striking differences at such close range, uppers stay subzero, markedly less northern encroachment of the milder air. Thoroughly fascinating to watch this!

I love your informative posts Cambrian, keep them coming. It shows the struggle milder air can have as it encroaches into colder air.

As you say very interesting model watching over the next few days.

I just wish I had half the knowledge of yourself and many of the other great contributors on here. Cheers.

[Derecho]

A lot of the GFS ens that push the Russian cold to Scandi get it pretty close to us!

Shame none of the operationals are buying into it which are poor this morning. The GFS control is though

A few humdingers in there....

A huge amount of scatter in the NE there more exposed to a potential cold easterly

However we need another operational to come on board soon for me to be convinced. The operationals this morning aren't good and whisk away the cold from Scandi. It would be a big setback if that happens.

[Lincs Observation]

Surely with the entrenched cold over Russia and Northern Europe any  warm air progression will be muted considerably as it tries to push against it.

the more entrenched the cold the more difficult to shift it will be, can only be good moving forward ?

[blizzard81]

It really is amazing how the 00z runs are flatter than the other runs. Let's hope they are wrong. 

Edited December 1, 2023 by blizzard81

[Met4Cast]

Next week aside, MJO progression continues to look good.

Should be in the mid Pacific by week 2 putting the Christmas period firmly inside the window of opportunity for cold/blocked patterns when combined with a rising AAM.

[LRD]

So, yet again the morning runs put everyone in a grump. Strange that it keeps happening. Odds favour milder weather now but if the 12z runs switch again who knows. What we don't want is the cold blown away from Scandi but even that happens on the ops this morning

[blizzard81]

4 minutes ago, Met4Cast said:

Next week aside, MJO progression continues to look good.

Should be in the mid Pacific by week 2 putting the Christmas period firmly inside the window of opportunity for cold/blocked patterns when combined with a rising AAM.

Cheers mate. I think we all needed some good news after viewing those ops this morning. 

[E17boy]

Morning peeps,

Hope you are all well. A very frosty Start here in Walthamstow NE London this morning although cloudy.

My hunch for where we are heading this is only my thoughts I may be completely wrong. I think at sometime sooner than later the Atlantic will make  inroads . Whether we like it or not we got to be ready for this cold to break somewhat over our shores. Probably temperature lifting to mild values for a while. Then what happens next? My gut feeling is we will probably see the cold grow again in Europe come towards mid December . Then I think fun and games will start where the Atlantic may well start to stall. This may eventually be pushed back west as we see the cold extend westward and we finally get some proper biting cold white Christmas ? who knows . But there is plenty of development waiting to ignite the fire.

I may be completely wrong here as have little evidence to back my thoughts but that’s my wishful thinking. Who knows what holds next in our winter journey but sure will be a ride to come.

Enjoy your Friday all

THE SEARCH FOR OUR WINTER WONDERLAND CONTINUES 

regards

[DJ Fart]

57 minutes ago, Chertseystreamer79 said:

Same old morning runs...

That depth of cold is gonna prove a problem for any model to break down. Happy advent! 

We hear this a LOT.  Last year showed that this isn't always as true as many on here believe.  We had deep cold that was brushed aside pretty effortlessly in the end.  I've got three excited children (and an excited dad!) here watching falling snow on Dec 1st.  It's already been a good winter in that respect.  I've found that coming on here less frequently during the day and simply summarising the last couple of pages is better for my mental health than poring over every run...but here's to the next chase!

[LRD]

It's clutch-straw time but for Stockholm the ECM was a very warm run compared to the ensemble suite

And there are still some brutally cold runs in there. However, let's not lipstick the pig - it's a poor morning. For closer to home the story is simpler. Mild

[Downburst]

You see it’s only a problem if you use the latest charts. Meanwhile yesterday using wetterzentral I was inadvertently looking at 24hr old ICON charts thinking my word that looks good compared to GFS. Gotten Himmel, for you ze 12z run is over.

[fromey]

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[LRD]

3 minutes ago, DJ Fart said:

We hear this a LOT.  Last year showed that this isn't always as true as many on here believe.  We had deep cold that was brushed aside pretty effortlessly in the end.  I've got three excited children (and an excited dad!) here watching falling snow on Dec 1st.  It's already been a good winter in that respect.  I've found that coming on here less frequently during the day and simply summarising the last couple of pages is better for my mental health than poring over every run...but here's to the next chase!

Yeah I always thought the 'cold-difficult-to-break-down' theory was a bit of a myth (putting it politely). But the Met Office mentioned it in one of their presentations recently so there's obviously something in it. Dense air being more difficult to replace sort of thing

Although I'm still interested in winter weather, I am nowhere near as invested in it as I was when my kids were younger. Never been one to analyse every run though. I'm philosophical about it all these days. Our winters are so poor now my expectations are always very low