Model output discussion - The run up to Christmas

[BlueHedgehog074]

12 minutes ago, Mr Frost said:

Morning all

Quick summary/snapshots from the latest UKV from Christmas Eve into the early hours of the 27th. 

NW/N/NE Scotland snow showers early AM on Christmas Eve.

24/12: 03:00

 

The above green blob out in the North Sea is what could land in Eastern parts of England later on that day and deliver a wintry mix! (See chart below) 

12:00

 

25/12: 18:00

Wet evening/night for West/Central Scotland.

 

26/12: 18:00

More widespread soaking and windy for much of NW UK and parts of Ireland. 

 

27/12: 03:00

Our next batch of cold air is moving in from the NW - wintry showers with snowfall over high ground at this stage for favoured areas. 

 

03:00

As always the above charts all subject to much change/timing at this range! 

All the best to you all! 

Morning! A good summary their. Should feel particularly festive for you guys up North over the next few days. And perhaps a chance for something more widespread, especially if those dream ECMWF snow depth charts posted above come off Though the type of pattern the charts show for next week with Atlantic ridging and Low Pressure over and to the East or South of the UK has the chance to produce a white surprise anywhere. Some things for us to look forward to, and as you illustrate, some wintry weather likely for some to the North in the next few days 

[georgiedre]

11 minutes ago, johnholmes said:

It is a long time since I have seen such a meridional 500 mb chart prediction close to the UK.

NOAA 6-10 

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

And the 8-14 is pretty similar; one would imagine at some point in the next 2 weeks some very cold air is possible?

Slight hints of an easterly on the 10 to 14 day chart

[Anthony Burden]

Matt Hugo stating troposphere running the show,low pressure from America running to the west of Greenland 

warmer air pushes north. continued cold looking more likely for U.K. into January snow is definitely 

becoming more likely to many parts of the U.K. in the next 7 to 10 days.

[northwestsnow]

EC ens look cold for London.

[BLAST FROM THE PAST]

2 hours ago, KTtom said:

Some nice charts on display again this morning, especially around the turn of the year, it seems in this country you have a choice, very cold and dry, or less cold but a greater chance of heavy precipitation, we can't have both here in the UK. The period to the end of the year looks like the latter.

This chart from the ECM is probably the one which caught my eye more than any this monrning...when was the last time you've seen the vortex like this at a time when traditionally its at its most organised..If we get Strat intervention there won't be anything left by the end of Jan! 

 

If ever there was a LIA synoptic chart then that would be it, so meridional.  And This without a SSW.  Looking at this build up XMas week cold set up is in the bag (just the nowcasting to start looking at), pity about my blast/beast from the east but the dropping trough n to s and HP to W/NW is there (but won’t seem to develop into my easterly) and cold week on cue so that’s pleasing.  For JH to post re the meridional set up....a very good indicator of the path ahead.
GFS 0z has that trough stuck over us after Xmas.....a lot of precipitation in there.

BFTP

[johnholmes]

19 minutes ago, georgiedre said:

Slight hints of an easterly on the 10 to 14 day chart

Not sure, the deep low predicted post Xmas in the N Sea is likely to pull the surface flow N of East but no Beast from the East. The overall upper air pattern remains from North of West into the European trough. Beyond 14 days is not my area.

[johnholmes]

A plea, first to BFTP, what is LIA please?

generally to all may I ask that for folk like me and newcomers if you use accronyms please explain them-thanks

Edited December 22, 2020 by johnholmes

[BLAST FROM THE PAST]

3 hours ago, V for Very Cold said:

Don’t get me wrong, I would love deep cold and snow events.... I was merely wondering should we water down our expectations for the next week?

Never a bad thing, then there’s extra excitement when/if it turns out to be very cold and snowy

 

BFTP

[Matt H]

A few snapshots from the GFS parallel run, looking cold and blocked for the foreseeable!

Edited December 22, 2020 by Frosty Winter

[KTtom]

8 minutes ago, johnholmes said:

A plea, first to BFTP, what is LIA please?

generally to all may I ask that for folk like me and newcomers if you use accronyms please explain them-thanks

Bearer of good news apparently.....according to Google anyway

[BLAST FROM THE PAST]

2 hours ago, That ECM said:

I appreciate we are talking about a t240 chart but wouldn’t the low coming out of the states go under the high thus keeping it in place?

If you look at the timeframe t216 to t240 and look at the direction of movement...it’s heading back inland and up the west side of Greenland and help to re-in force the building Greenland High Pressure....it won’t come across the Atlantic if it pans out like that.

 

BFTP

[Speedbird]

2 minutes ago, KTtom said:

Bearer of good news apparently.....according to Google anyway

 

2 minutes ago, KTtom said:

Bearer of good news apparently.....according to Google anyway

Little Ice Age ? 

[Met4Cast]

9 hours ago, Geordiesnow said:

Met4Cast is correct when he said there is no Greenland high forecast and its just an Atlantic ridge heading into Greenland and that is what I'm seeing. What orientation that ridge will end up as and how far it heads into Greenland remains to be seen but it does seem to be a big ask to get uppers of below - 5 in this set up regardless. That said, even if we got uppers of -10 I would still be cautious and not believe it until its closer to the time so things could change for the better but the overwhelming evidence would suggest that won't be the case. 

 

Indeed - I'm not too worried re: 850hPa temperatures at the moment, as we saw back in early December with the snowfall across the SE, marginal situations can deliver when you're not expecting them too. Having said that, I think some might be getting a bit ahead of themselves with excitement for this up-coming pattern, it's looking increasing like as typical late December affair rather than anything overly exceptional, even the blocking continues to be watered down on latest runs, UKMO is the best of the bunch with better ridging into Greenland, though it could be over-doing that slightly looking at the GEFS/EPS means. 

EIther way, it'll feel pretty chilly at the surface, especially in the N. We just have to hope we can see colder 850hPa;s closer to the time.

[Uncertainty]

Morning all!

Still uncertainty over the precise track, shape and precip distribution of tomorrow’s low. Snow looks limited to the tops of the Cumbrian fells and Pennines so rain is the main focus.

Icon has the heaviest rainfall focused through the Bristol Channel into Southern East Anglia.

Arpege is pretty similar

Euro4 has the main band slightly further North highlighting the continued uncertainty.

 
 

Now, back to the future...
 

What a chart from the GFSp.

Cut off block forming over Greenland, a developing NErly, troughing all over Europe, the slack flow and building snow cover on the ground would enhance the snow risk. And still the Russian high promoting +EAMT to toast the SPV.

Blizzard incoming for the SW? 

ECM op is just the better side of marginal this morning and has lots and lots of snow for lots and lots of people. Would please a lot of members on here. A lot of tricky micro scale synoptic reasoning ahead for the pros, that’s for sure!

Support in the EPS for the blocking to the NW and NE of the UK to continue, if not strengthen after day 10 
 

With the continuing developments in both the troposphere and the stratosphere there will be plenty of model output for us to discuss going forward...

[Skullzrulerz]

5 hours ago, mountain shadow said:

An all mighty wet slush fest away from hills and mountains and we're still chasing proper cold in the + day 10 range.

Still time for change though.

I have to agree with what you are saying 

It's been awfully quiet here unlike the pages that we use to have over a set of runs? 

So I decided to have a quick look at the models this morning ICON (which has strangely disappeared into thin air) as well as the ECM

Unless you're living on a hill somewhere or live in Scotland you might be for a snowy day or two 

For the most of us we're going to be seeing some lovley rain (cold on the plus side) which everyone was expecting unfortunately 

In this case silence can speak a lot louder then words here and this is the case today

And please don't get yourself too excited regrading snowfall charts especially a week out they have been proved to be unrealistic and unreliable as in reality it will be snowfall for higher ground and more favourable parts of northern England and Scotland 

 

Edited December 22, 2020 by Blessed Weather
Comment removed

[Battleground Snow]

Trough a tad more south east here at 168 and it looks like it will have another go at a Greenland high towards 216 again.

 

[That ECM]

Upgrade in the 850’s. They are important right?

[Matt H]

4 minutes ago, Skullzrulerz said:

I have to agree with what you are saying 

It's been awfully quiet here unlike the pages that we use to have over a set of runs? 

So I decided to have a quick look at the models this morning ICON (which has strangely disappeared into thin air) as well as the ECM

Unless you're living on a hill somewhere or live in Scotland you might be for a snowy day or two 

For the most of us we're going to be seeing some lovley rain (cold on the plus side) which everyone was expecting unfortunately 

In this case silence can speak a lot louder then words here and this is the case today 

If you were expecting a cold "spell" with snowfall expected across large parts of England then you might as well go and play the lottery and have a better chance of winning that 

And please don't get yourself too excited regrading snowfall charts especially a week out they have been proved to be unrealistic and unreliable as in reality it will be snowfall for higher ground and more favourable parts of northern England and Scotland 

 

Do you ever have a day off?

[ALL ABOARD]

Well personally for me it's nice to be looking for chances of snow and a downward temperature than checking where is going to flood next or wondering what temperature record were going break. 

 

 

Yes the Greenland ridge is now toppling but the stubbornness of it to topple over us is completely different from previous years. 

Edited December 22, 2020 by ALL ABOARD

[mushymanrob]

47 minutes ago, georgiedre said:

Slight hints of an easterly on the 10 to 14 day chart

Yes, i think thats where these charts could go, theres a slight pressure rise to our north, troughing sinking south..  This winter really has great potential for some proper winters weather and its no exageration to think its going along similar lines to 78/9, 84/5 ..... and im no coldie... We are heading for a lengthy spell of cold unsettled...

 

[KTtom]

Small changes again..for the better, north easterly at day 7 sub -5 uppers digging into France and the Atlantic ridge heading north again...all at day 7!

 

[BLAST FROM THE PAST]

 

that’s easterly enough for me

 

BFTP

[sheikhy]

1 minute ago, mushymanrob said:

Yes, i think thats where these charts could go, theres a slight pressure rise to our north, troughing sinking south..  This winter really has great potential for some proper winters weather and its no exageration to think its going along similar lines to 78/9, 84/5 ..... and im no coldie... We are heading for a lengthy spell of cold unsettled...

 

Good to see you on the cold wagon mate!!when your mentioning cold and snow then something is defo stirring up!!!❤

[Battleground Snow]

1 minute ago, KTtom said:

Small changes again..for the better, north easterly at day 7 sub -5 uppers digging into France and the Atlantic ridge heading north again...all at day 7!

 

Looking good... It's why we shouldn't get hung up on uppers until we get within 96 hours 

[Chesil View]

53 minutes ago, Anthony Burden said:

4 minutes ago, mushymanrob said:

Yes, i think thats where these charts could go, theres a slight pressure rise to our north, troughing sinking south..  This winter really has great potential for some proper winters weather and its no exageration to think its going along similar lines to 78/9, 84/5 ..... and im no coldie... We are heading for a lengthy spell of cold unsettled...

 

I’ve been thinking exactly the same thing Mushy.

Edited December 22, 2020 by Broadmayne blizzard