Model output discussion - another cold spell on the horizon?

[Man With Beard]

This retreating front with snow is starting to pop up on a number of models Thurs night 

 

[Djdazzle]

1 minute ago, Frostbite1980 said:

The energy coming out of the US is going to go over the ridge and flattern the pattern in future frames IMO

You ate probably correct, but who cares at that range? We are discussing a day 10 chart in deep deep FI when the models are diverging at 96!

[Tim Bland]

7 minutes ago, CSC said:

For the doom and Gloomers, it’s clear GFS OP is an obvious outlier and its fiat to say the models don’t have a clue what’s going on even at t48, t72. Check these 2m temp forecasts from the ensembles tonight. Some say 9c, some say freezing at 0c. The GFS are clueless   right now! 

 

 

Doesn’t look as much of an outlier for London? Perhaps it’s just the south coast?

[Jason H]

1 minute ago, Frostbite1980 said:

The energy coming out of the US is going to go over the ridge and flattern the pattern in future frames IMO

10 days away? I'm not too concerned. We haven't got agreement at 5 days. It's pointless fretting about a scenario at this time frame. Personally, I'm really enjoying this period of model watching. Like the majority, I want cold and snow. It's all the fun of the ride. It's only the weather.

[john mac1]

No negativity from me. Possible snow event on Thursday and no sign of anything zonal. 
 

we’re in the game!!

[Tim Bland]

3 minutes ago, Man Without Beard said:

This retreating front with snow is starting to pop up on a number of models Thurs night 

 

Strong signal on GEFS as well..

[Frostbite1980]

3 minutes ago, Jason H said:

10 days away? I'm not too concerned. We haven't got agreement at 5 days. It's pointless fretting about a scenario at this time frame. Personally, I'm really enjoying this period of model watching. Like the majority, I want cold and snow. It's all the fun of the ride. It's only the weather.

Totally agree that is why I said I had seen enough. I was only commenting on the latter part of the run.

[Allseasons-Si]

In short,...thats not a bad set of 18z gefs ens,...for London...

Edited January 10, 2021 by Allseasons-si

[Mike Poole]

6 minutes ago, bluearmy said:

Not to put too much of a downer on the evening but that T222 para is a very similar height pattern to the ec mean ...... nite ...

    

Surprised to see you compare a T222 op run with an ensemble mean?  

Models are a total mess today.  I wouldn’t believe any of them.  

[Frostbite1980]

3 minutes ago, Allseasons-si said:

In short,...thats not a bad set of 18z gefs ens...

I will happily take that

[Vikos]

Fresh EC 12z Scenarios, beginning with +72 and 3 Clusters! 6 clusters already in +144h!

This 12z is messed up!

    

      

 

[Tim Bland]

Has anyone tried turning the GFS off and waiting for 20 seconds before turning it back on

[CSC]

5 minutes ago, Tim Bland said:

Doesn’t look as much of an outlier for London? Perhaps it’s just the south coast?

Possibly. Personally I believe if it can’t get the first 72 hours right then from then onward might aswell be disregarded. It’s possible all models are wrong! Back to the drawing board tomorrow!

[Djdazzle]

1 minute ago, Tim Bland said:

Has anyone tried turning the GFS off and waiting for 20 seconds before turning it back on

Or just turning it off . . .

[CSC]

What I find quite extraordinary is we are a day closer and we STILL don’t know what is going on in just a few days time! Phenomenal times. 

[Matt H]

10 minutes ago, Man Without Beard said:

This retreating front with snow is starting to pop up on a number of models Thurs night 

 

Nice to see something decent for the East Anglian coldies.

[Lampostwatcher]

18Z 

Has a possible snow event 

For Thursday 

 

[MJB]

Control still looks ok

[mountain shadow]

19 minutes ago, Kentish Snowman in Yorks said:

Eh?  I'm sure the landing point for proper cold has been 20/21 January for days now?

That is still 240 hours away based on the current output?

Indeed. But if we don't see an improvement in the next 24-48 hours, the cold can will be getting kicked further down the road.

 

[Kasim Awan]

15 minutes ago, Man Without Beard said:

This retreating front with snow is starting to pop up on a number of models Thurs night 

 

Yes - this is gaining momentum now on GFS / others for Thu night.

Initially on Wednesday the front produces a risk of snow to rain, primarily above 100m north east of Derbyshire before a transition to rain. The 850mb 0C isotherm is then tracked slightly west on Thursday as the front pushes west too, producing a more favourable adiabatic environment. This will be expressed given favourable evaporative cooling so largely dependent on intensity below 300 metres. The risk is there for a slow precipitation change to lower levels esp given the way some models are projecting intensity now - which is over 2.5mm / hour for a fairly wide area NE Derbyshire initially on Thursday. Also note a gentle easterly wind is crucial for elevations between 0 and 300 metres getting their temp down closer to 0, this projected to happen later on Thursday again increasing the risk of snowfall.

Into Thursday night the front tracks west once again with uppers falling, surface temperatures largely conducive too. Bit of an easterly flow near the coast largely limiting wintry precip within 10 miles of coast. Inland needs to be watched imo for a rain to snow event. The stalling nature of this front needs to be watched too - esp if the snow line is effectively lowered early on with a stalling band & a gentle easterly flow - potential for quite a few cms of accumulation locally. So this is the potential, lets watch how projections model intensity & positioning which are key here. 

Edited January 10, 2021 by Kasim Awan

[Frostbite1980]

15 minutes ago, Djdazzle said:

You ate probably correct, but who cares at that range? We are discussing a day 10 chart in deep deep FI when the models are diverging at 96!

This is the model output thread no? So whether likely to happen or not surely I can put my view forward?

[Mapantz]

The UKV longer range has been toiling with the idea of snow in the Northwest in to Scotland Wednesday in to Thursday:

  

[MATTWOLVES 3]

22 minutes ago, Mr snowman 2018 said:

Yet again we are chasing charts again in the fi timeframe I’m afraid anything decent is always +192 hours plus This SSW could easily affect the USA and we stay on the mild side unfortunately I see this scenario playing out this time around ! 

Know matter how you look at it,we are going to be counting down to a cold spell...They rarely appear overnight,and its all about spotting trends and patterns at this far out..And I'm certainly not chasing 10 day charts...I've witnessed snow on several occasions these past couple of weeks and numerous widespread frosts...So considering what some are saying,we have yet to witness any winter...what I have failed to witness so far,is a raging West to East Zonal pattern that does not relent...so i would say things look pretty good.

And regarding SSW could easily be favouring the USA...far to early to say...we have second possibly 3rd even fourth warming events coming up which will know doubt open up other avenues. Its easy to adopt a glass half full approach,and is often the case when people have yet to witness anything favourable in there location. Lots going on and plenty more dramas know doubt..

Talking about day 10...looks cold with increasing snow risks..

[Sweatyman]

3 minutes ago, Kasim Awan said:

Yes - this is gaining momentum now on GFS / others for Thu night.

Initially on Wednesday the front produces a risk of snow to rain, primarily above 100m north east of Derbyshire before a transition to rain. The 850mb 0C isotherm is then tracked slightly west on Thursday as the front pushes west too, producing a greater risk of snow. This fuelled by evaporative cooling so largely dependent on intensity below 300 metres. However, the risk is there for a slow precipitation change to lower levels esp given the way some models are projecting intensity now - which is over 2.5mm / hour for a fairly wide area NE Derbyshire initially on Thursday. 

Into Thursday night the front tracks west once again with uppers falling, surface temperatures largely conducive too. Bit of an easterly flow near the coast largely limiting wintry precip within 10 miles of coast. Inland needs to be watched imo for a rain to snow event. The stalling nature of this front needs to be watched too - esp if the snow line is effectively lowered early on with a stalling band & a gentle easterly flow - potential for quite a few cms of accumulation locally. So this is the potential, lets watch how projections model intensity & positioning which are key here. 

Birmingham eastwards perhaps Thurs evening?

[Djdazzle]

2 minutes ago, Frostbite1980 said:

This is the model output thread no? So whether likely to happen or not surely I can put my view forward?

Absolutely. As I am able to put my view across. I know you were quoting somebody else, and it was not meant to be a criticism.

Edited January 10, 2021 by Djdazzle