[Model Output Discussion. 3/12/2022. How cold will it get?]

Just now, Stuie W said:

Oh how very snail... love it.

 

Absolutely cracking December chart! Cold air well and truly established across the entire U.K. , PV on holiday on the other side of the globe, nice Griceland wedge and a potential hurricane (not really) prepping to provide the mother of all blizzards to the middle of the U.K.  

not bad for day 5 of winter in the MOD.

[Model Output Discussion. 3/12/2022. How cold will it get?]

Just now, danm said:

A positive development I presume?

Nobody knows…..:) 

[Model Output Discussion. 3/12/2022. How cold will it get?]

3 minutes ago, MATTWOLVES said:

Thanks for putting my mind at rest guys.

Cold snap over...Big snow event...cold and dry.

Yep..pretty sure it's gonna be one of those outcomes

 

Locations - opinions- expectations- expertise  that’s the MOD thread at its best

[Model Output Discussion. 3/12/2022. How cold will it get?]

38 minutes ago, ICE COLD said:

UKMO T144 not to sure ? 

Just look at Northern Canada….the PV is completely missing! That’s very rare. 
 

Im thinking the current state of the NH means we don’t have to chase every Op run, as the foundation for better Synoptics isn’t necessarily do or die !

[Model Output Discussion. 3/12/2022. How cold will it get?]

1 hour ago, Frostbite1980 said:

Surely if this run continues the low would move towards Northern Italy bringing colder 850's in from the east?

 

Just one blizzard and I’m happy  

57 minutes ago, CreweCold said:

If people want more than just convective snowfall in narrow streamers then we have to ride our luck a bit with these systems. If it comes off, some people could have 20cm of snow on the ground for a week.

Couldn’t agree more Crewe.

The historic and memorable snow events have come from Synoptics just like that which are being modelled. (For some/many)

We are coming into a period of cold that is so pronounced the MOD thread will become IMBY without obvious IMBY posts.  We naturally look at our own area when posting our thoughts on the runs.

Overall with the NH pattern as it is it’s best for U.K. cold and we just gotta ride the wave

[Model Output Discussion. 3/12/2022. How cold will it get?]

24 minutes ago, Lukesluckybunch said:

But what about the milder spell..between 168-192

If you want heavy frontal snowfall you need the cold/milder boundary to meet. The moisture is held within the milder air.

ECM is perfect as the cold pushes back! Meaning those staying on the right side of the boundary hit the jackpot (and that’s a fair chunk on the 00z

[Model Output Discussion. 3/12/2022. How cold will it get?]

2 minutes ago, Ali1977 said:

That’s a great chart, poss snow event in the south with even colder air heading in 

Cotswolds would be getting absolutely hammered with snow! Along with many others!

[Model Output Discussion. 3/12/2022. How cold will it get?]

We all remember the Iberian low dramas at 144+ ……. Look where it ended up, zero mild uppers feeding into the U.K. 

Just something to keep in mind when looking at the 168-240 charts, especially in this kind of set up.

[Model Output Discussion. 3/12/2022. How cold will it get?]

18 minutes ago, Met4Cast said:

So at which point do we stick the GFS into the “cannon fodder” folder?

Is it really cannon fodder? With a synoptic pattern so far from the ‘average’ surely you’d expect plenty of variation beyond the more reliable time frames.

Yes, if there is going to be a marked shift in broad scale patterns, ie, zonal flow to a blocked pattern then the day 8 + charts can pick a pattern change, but once we have a -NAO and AO with a major block in place surely we have to accept the models will simply be less reliable in the mid term. 
 

An open interpretation is needed more than normal IMO

[Model Output Discussion. 3/12/2022. How cold will it get?]

1 minute ago, Ali1977 said:

Sliding hurricane into an easterly????? It’s so complicated , storm could actually move West

At 234 it’s anyone’s guess in this set up. However the shortwave exiting the main low could be snow maker for the m4 north …;) 

[Model Output Discussion. 3/12/2022. How cold will it get?]

The fact the trough is so slack with little wind, means we can not underestimate surface conditions.

At this time of year with little solar input and no mixing we could well be looking at the coldest surface conditions for mainland UK (England and wales especially) that we have seen for many years!!

-10s overnight for Benson I would think, if not colder. 

 

UKMO 144.

[Model Output Discussion. 3/12/2022. How cold will it get?]

49 minutes ago, Kasim Awan said:

man if we can deliver that low to italy then the potential to our NE is crazy....

It’s certainly a very deep low, but cut off at this point, with a very southerly track. 
 

Cold preference is it disrupts as it moves towards the U.K. and produces a southern U.K. Blizzard, or it stays south and pulls in even more cold (but without frontal incursion) air from the east. 
 

Worst case is it spins up to far north introducing milder air from the south. 
 

Lots to be decided yet into the mod term

[Model Output Discussion. 3/12/2022. How cold will it get?]

4 hours ago, CreweCold said:

It's all going on...GFS sends the Atlantic troughing packing SE. In doing so it tightens the gradient over the UK and brings a snowstorm into the country

 

As someone who live in the Cotswolds this is an historic kind of chart. That would be some blizzard ! :0 

 

Quite incredible charts this morning! 

[Model Output Discussion - moving into Winter]

Can see GFS 6z was away from the cluster on the 850s plot (short ens LONDON) mild outlier.

.

 

 

 

[Model Output Discussion - moving into Winter]

As soon as I saw last nights ecm on wetter last night I thought it prob best to avoid the MOD thread till this morning

Glad I did lol. 
 

Much better run from ECM this morning, and all models continuing the theme of the cold trough dropping down. 
 

Beyond mid week still a lot to be decided on depth of cold, any potential snowfall and longevity of the cold. 
 

ideally we want a clean drive of the coldest uppers possible, then a slack trough, followed by a channel low then a cold surface high to set up………

Plenty more ups and downs to come.

 

[Winter 2022/23 - Moans, Ramps & Chat]

3 hours ago, E17boy said:

Hmm I am excited but just raead the weatheronlines week ahead outlook the end has distressed be a bit. Atlantic breaking through after next weekend????? unless they have got it wrong 

The data is the same for us and weather online’. We interpret the data just as they do. 
 

I’d be confident we have plenty on here as skilled, if not more so, than the people who write for these weather websites.

Stick with the MOD thread for day to day interest, as the bigger picture becomes clearer (and closer) the Metoffice or BBC are safe bets as well 

[Model Output Discussion - moving into Winter]

1 hour ago, fromey said:

A some encouraging comments from Ian Ferguson.

Ensembles for Stroud  woohoo lol.

[Model Output Discussion - moving into Winter]

30 minutes ago, terrier said:

Sorry guys but that ECM won’t verify. And I will tell you why……. Just been out and bought 3 sledges

Get em In the shed ready and waiting while they are still available!!  

[Model Output Discussion - moving into Winter]

2 hours ago, Tamara said:

And here it is. The retrogressing block signal that is now fully advertised by numerical models.  Very robust -ve East Asian Mountain Torque (shaded blue above 30N and the red line on the torque graph) essentially creating an extra tropical wind-flow vacuum in the Pacific as the starting pistol to a powerful downstream retrograde signal. As suggested yesterday it's a biggie, and there are ramifications from this signal for quite some time to come which is the fascination for me.

The question remains long term how far the retrograde evolves and how the -ve NAO behaves accordingly. The intuitive reasoning remains that attritional battle ground towards NW Europe culminates in an attempted breakdown - which tries to re-set to another Atlantic trough and amplifying downstream ridge. Does the Eurasian feedback reload this as another Scandinavian block, or, does the polar jet then prevail and create a more traditional zonal pattern with heights across mainland Europe?   

Finely balanced in my neutrally objective opinion as much more work will be required from the tropics next time round to assist, with angular momentum at a lower base level than it has been up to this -VE EAMT. Reasoning behind that has been given fully already this week.  I don't personally, at this time, believe the Eurasian feedback signal on its own is enough.

However, all of that is some way ahead. From my own point of view though, the evolution of the diagnostic remains the focal interest.

 

Absolutely Tamara, the daily model runs will ultimately inform us of the eventual outcome. Lots of fun to be had following the events. Hopefully you’ll come along for the ride, that is what makes the MOD such an interesting, informative and addictive place to be. All levels of expertise deciphering all sorts of fluctuations from the models.

Absolutely love it  

[Model Output Discussion - moving into Winter]

1 hour ago, CreweCold said:

If I had to bank a run, it'd be the control run btw

Absolute peach of a chart that! :0

[Model Output Discussion - moving into Winter]

Thankfully we can concentrate on the 18z rather than what the weather in January will be

[Model Output Discussion - moving into Winter]

3 hours ago, Ali1977 said:

UKMO at T168 looks fine to me

When the trop PV is split, displaced and half the NH is loaded with high pressure then we all know times are good.

Tamara can post as many big words as she likes (and underline odd letters) but @Ali1977 will always post the charts  

[Model Output Discussion - moving into Winter]

Fine margins regarding the Iberian low and how much influence it has.

UKMO and ECM not to different at 168 broadly speaking, but EC, with the low stronger and further north, drags up the milder 850s vs UKMO which allows the high to ridge into U.K. continuing the feed of colder air. 
 

UKMO 168

 

EC 168

It’ll no doubt change over coming runs.

[Model Output Discussion - moving into Winter]

Iberian low trending south/less intense on 6z GFS and ICON 12z. We stay on the cold side on both. 

[Model Output Discussion - Deeper into Autumn]

3 minutes ago, MATTWOLVES said:

Cherry picking implies there's only a select very few to choose from..but there's a huge number of them. And this is me taking a stab at the potential for a cold snap a little further down the line.

This is a forum mate and it's all about putting your neck on the line and seeing how it may evolve.

This is know different than someone pointing out the teleconnections are about to change so the conditions may become milder or colder in a few weeks!

Big respect Matt, don’t get me wrong I love all these charts.

Ensembles for 240-316 are spread (as you’d expect. More cold than mild though)  trend is good.