Model Output Discussion - Into 2024

[Penrith Snow]

For those of us old enough to remember it is striking the similarities between today's model runs and the first week in December 1981.

Then as now a large uk high migrated towards Greenland with very cold Northerly winds pushed southwards, in 1981 a slider low running SE along the base of the cold front brought heavy snow to Central and Southern England on the 8th with London paralysed during the morning rush hour.

The previous day had been relatively mild but the low quickly pulled in the very cold air mass and rain rapidly turned to snow during the early hours.

The Greenland High weaked slowly over the next two weeks but the UK remained to the north of the Jet and it remained cold and snowy until the New Year

December 1981 is now overshadowed by 2010 but in many ways it was more snowy.

Remarkable synoptics today not seen for many years.

Andy

[Battleground Snow]

Solid mean at 156!

Expect the graph to trend down again later

[Zero Visibility]

Morning all, just catching up. GFS

 

 

 

[festivalking]

2 minutes ago, Lukesluckybunch said:

Cold and blocked deep in the run...wedges appearing around iceland.

Wedges make sledges!

[BarometerCat]

Wowsers ,epic cold if we get anything like this!

Main thing for me is the general trend emerging from 14/15th. 

great charts!

[Midlands Ice Age]

 

3 hours ago, Met4Cast said:

Some won’t be happy until we see a return to snowball earth and even then I’m sure they’d find a reason to complain. 

Great modelling across the board this morning, the GEFS extend the cold (using -5C isotherm as the guide) another day or two with a tighter clustering of cold members. 

Details chop and change but the broad direction of travel remains the same. The GEM & UKMO are pick of the bunch for me. 

I think that I might qualify   in that category   

3 hours ago, Harveyslugger said:

People expecting an ice age

Well just look at my name....  Of course I am.                  Maybe not reaching the south coast... but the M4 will be OK.

Seriously though?...... I am waking from my 50 years of snoozing... My alarm clock went off early this morning when the sea ice extent figures from JAXA appeared and we have the highest amount of sea ice for the last 21 years. It is now greater than it was in the 2000's. 

There is enough cold air in the Arctic at the moment for everyone to share. 

PS... I have no idea why....... especially when apparently worldwide temps are so high. Even the Antarctic extent has rapidly caught up with its averages!!.

MIdlands Ice Age

 

[northwestsnow]

Just now, festivalking said:

Wedges make sledges!

Yep and it's as true today as it will be in 50 years time ...

 !! At least I'll  have a legacy somewhere

[Malarky]

6 minutes ago, Turnedoutniceagain said:

 

Not sure I've seen a better one in a semi-reliable timeframe?

 

Wishbone vortex. Leave it on the windowsill for a few days and then annoy your sister by snapping it before she gets chance.

[MATTWOLVES 3]

6 minutes ago, Zero Visibility said:

Morning all, just catching up. GFS

 

 

 

You know something mate..your new to this forum,and I already like your style

[Methuselah]

48 minutes ago, Captain Shortwave said:

A much much better first plunge of cold air, arriving across the south around early afternoon on the 15th.

This time yesterday, I surmised that Days 8,9 and 10 were looking 'nippy'. Hopefully, it'll now apply to Days 7,8 & 9. . . The tension is building! 

[Gowon]

That Vortex is properly getting slapped around up there:

It's starting to fight back towards the end though:

[Turnedoutniceagain]

15 minutes ago, BarometerCat said:

Wowsers ,epic cold if we get anything like this!

Main thing for me is the general trend emerging from 14/15th. 

great charts!

Look at the 528 !!!

[nick sussex]

The GFS 06 hrs run gets the thumbs up from me .

Very nice and a much cleaner evolution with a bit more margin for error .

[rwtwm]

7 minutes ago, Gowon said:

That Vortex is properly getting slapped around up there:

It's starting to fight back towards the end though:

Not so much Fantasy Island, as an outcrop in the furthest reaches of the Fantasy Archipelago but... 

That's one hell of a tasty slider at the end of the GFS run.

[Gowon]

We may be looking at a BFTE late Jan.

[northwestsnow]

Control day 8 /9

[MATTWOLVES 3]

10 minutes ago, Gowon said:

That Vortex is properly getting slapped around up there:

It's starting to fight back towards the end though:

We are in unchartered territory I feel..i would say how at this range the models will nearly always revert back to a climatology normal,reform the PV and put it back in its natural home. And they will do this more with a pattern we have now and are struggling with a desired solution. Background drivers could well be giving the pattern another kick at this point also! 

Obviously we don't want to be seeing a strong pv towards the NW at this stage as it can literally rule the roost and override other forcers! But going on what I'm seeing currently and those met updates I've got a feeling the pv could be remaining weak for the duration.

Significant cold clustering out towards mid month on the ens

Edited January 8 by MATTWOLVES 3

[CameronWS]

I have a question! Follow the deep cold plunge a breakdown involving a short period of cold zonal is consistently showing. This often very marginal for my location but at least provides moisture. Would the cold plunge directly before it and already entrenched cold increase the likelihood of snow instead of rain?

[northwestsnow]

6z control is an absolute ripper

[Paul_1978]

30 minutes ago, Turnedoutniceagain said:

 

Not sure I've seen a better one in a semi-reliable timeframe?

 

The question is for most of us, will such a pattern give us showers with negligible accumulations, or something frontal and more prolonged? Too early for the detail for sure, but broadly speaking?

[That ECM]

4 minutes ago, Paul_1978 said:

The question is for most of us, will such a pattern give us showers with negligible accumulations, or something frontal and more prolonged? Too early for the detail for sure, but broadly speaking?

Within the pattern all options are possible as only when it gets to T48ish will small details be seen. Look at the se today.

[nick sussex]

Just looking at the sat pic for midday French time and noticed this long almost continuous narrow cloud band . I wonder if it’s a trough . And yes I need to get out more !

Edited January 8 by nick sussex

[Singularity]

 

The mid-stratosphere modelling has made for an interesting watch this past week and probably has played a role in the uncertainty regarding how strong the tropospheric polar vortex lobe over N. America will be, hence how strongly the Atlantic lows attempt to push cold weather out of the UK next week.

First off there's a week split this Wed-Thu, followed by a partial merger on Fri, followed by a more pronounced split Sat-Tue. It remains to be resolved how strong the vortex above N. America is, hence the uncertainty with what goes on below.

Incredibly, there are hints it may attempt to split yet again later next week, though the latest run wasn't as interested as the 00z.

[phil nw.]

It looks like we have some exciting model charts to come during the next couple of weeks especially if looking for cold and later snowy weather.

Current conditions show the cold easterly is now established as we can see from the temperatures and uppers coming from a very  cold continent.Generally a drier week to come but some snow showers already showing for a few areas and this risk especially further south continues until tomorrow.

 

 

We have 3/4 days before the change over to the well advertised retrogressing high ,underway from Friday.

Pretty good agreement now that we get sufficient ridging north west to eventually see the colder air return from the north,again on time around 15th.

Solid overnight  mean 850hPa anomalies ensembles  for day 10 showing the cold blocking established with Greenland heights and the Scandinavian trough to the north east extending into Europe.By this time the Arctic cold is over the UK.

 

Where we go from there looks interesting,some later ensemble guidance shows the Atlantic moving in from the south west which may well result in a battleground snow event somewhere across the uk.

For now despite the recent differences in operational outputs we seem to be honing in on this change so steady as she goes with plenty for coldies to look forward to.

 

 

Edited January 8 by phil nw.
spelling

[MattStoke]

4 minutes ago, North Easterly Breeze said:

Just fyi, that snow in the SE was a complete non event. Air temps too high it seems, several days of dry, cold needed, so no rush with that northerly.

The coldest air is only just moving in and showers clearly developing on the radar. 

Mid afternoon on the UKV: