Model Output Discussion - Colder but how cold and for how long?

[IDO]

The EC D8 is more like the D9 mean than the 0z op, as expected:

[on the coast]

Well to 96 the ECM is good. No point in taking anything further. 

[Captain Shortwave]

Monday surely has to be approaching the point where that north to north west flow might deliver something.

   
 

It wasn’t long ago that Monday was looking like a northerly quickly backing westerly during the day. Now this flow persists until Tuesday morning. It is one to watch because you could rule out bands of showers pushing south from northern Scotland that are currently not being picked up at this range.

[Ali1977]

Fax vs ECM at 120, pretty similar I reckon. 

Just now, Ali1977 said:

Fax vs ECM at 120, pretty similar I reckon. 

Although saying that, the fax looks better still holding a northerly to the east of Iceland 

[Metwatch]

2 minutes ago, Scott Ingham said:

Yeah and many more features will pop up for sure! We won’t know till Saturday at the earliest for Monday - Wednesday

Very true, but frontal clashes with cold air will almost always be better in terms of being widespread, so more are in with a chance of snow, especially central areas. I know which one myself and those in Midlands prefer, but those living close to coastal areas prefer the latter which I still respect.

[IDO]

So with EC moving in line with the ens, we can see longevity being to D8-9. In that case, I would rather have the low from the Azores further north for a snow event before we head back to the westerly regime. D9:

The low undercutting south may lead to some surprises but a big snow event is my pick. 

[offerman]

21 minutes ago, Malarky said:

PLEASE bring it home UKMO. Bank x100.

Could you post a link for me please where i can view these met office charts. Thanks 

[Ali1977]

1 minute ago, offerman said:

Could you post a link for me please where i can view these met office charts. Thanks 

Fax Synoptic Charts From The UK Met Office - Neweather.tv

WWW.NETWEATHER.TV

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Latest Met Office Fax synoptic weather maps

 

[Scott Ingham]

1 minute ago, Metwatch said:

Very true, but frontal clashes with cold air will almost always be better in terms of being widespread, so more are in with a chance of snow, especially central areas. I know which one myself and those in Midlands prefer, but those living close to coastal areas prefer the latter which I still respect.

The issue with frontal clashes is it tends to be a day of snow then mild air coming in 48 hours later. I prefer to keep the cold in and get several troughs shortwaves in a flow for a week or two. But each. To their own I guess!

[Mike Poole]

JMA clean at T96 too:

Similar evolution to ECM after, possibly more snow.  I think we are now in a good position at T96.

But I think the period T120-T168 is not yet nailed on any of the models.  I think the move to deflate the ridge and close the separation of the two lobes is overstated by the models, and will maybe take place slower or even not at all.  

[mountain shadow]

Just now, markw2680 said:

Personally I cannot stand northerly’s it’s always just wishbone crap, 

We're not really getting a Northerly though, the shortwaves between Scotland and Iceland have put a dampner on that.

[Bricriu]

Just now, Scott Ingham said:

The issue with frontal clashes is it tends to be a day of snow then mild air coming in 48 hours later. I prefer to keep the cold in and get several troughs shortwaves in a flow for a week or two. But each. To their own I guess!

Well that is a big ask, despite the suggestion from some  that cold may hang on past next weekend it doesn't seem likely now whether we have a frontal event or not, but I agree it could lead to a big dump of snow more widely  for a lot of people who will likely  be dry otherwise.

[That ECM]

The track off the low nowhere near sorted imo.

[Ali1977]

2 minutes ago, That ECM said:

The track off the low nowhere near sorted imo.

JMA would agree 

[Captain Shortwave]

3 minutes ago, Mike Poole said:

JMA clean at T96 too:

Similar evolution to ECM after, possibly more snow.  I think we are now in a good position at T96.

But I think the period T120-T168 is not yet nailed on any of the models.  I think the move to deflate the ridge and close the separation of the two lobes is overstated by the models, and will maybe take place slower or even not at all.  

Worth noting the JMA brings organised precipitation down from the north west as the channel low clears eastwards (thanks to another secondary low developing over the north of the UK), which would likely deliver a snow event.

Heights look very low and the airmass will be very cold. Lots of potential but it would be nice to see the models picking something up more broadly.

[Scott Ingham]

1 minute ago, Bricriu said:

Well that is a big ask, despite the suggestion from some  that cold may hang on past next weekend it doesn't seem likely now whether we have a frontal event or not, but I agree it could lead to a big dump of snow more widely  for a lot of people who will likely  be dry otherwise.

If you read Tamara’s take there are wedges that won’t be picked up until 120s. I agree the end back mild winning at day 9 but I wouldn’t put my mortgage on it if wedges send low pressure into Europe and keep us on the right side of the jet. That’s something to keep an eye on and until I see it I have to go with the ensembles atm and say I agree mild “should” be coming in 9 days time. Just watch this space….

[Purga]

Business as usual resumes. HP over Iberia, wet windy & mild.

[Tim Bland]

ECM is worst case scenario for the south if it’s snow you’re after. South of Birmingham it delivers almost nothing. The north get a couple of days of snow cover end of the week before it warms up  

[mountain shadow]

1 minute ago, Bricriu said:

Well that is a big ask, despite the suggestion from some  that cold may hang on past next weekend it doesn't seem likely now whether we have a frontal event or not, but I agree it could lead to a big dump of snow more widely  for a lot of people who will likely  be dry otherwise.

Next week doesn't look anything special snow wise at all now away from the North East.

Bits of snow here and there then a quick return to wet and windy with some transient snow as the mild moves back in.

Still time for change of course, but it all looks a bit meh to me despite the positivity of the background teleconnections. 

[Snowy L]

ECM -3 NAO to + 3 NAO in a couple of days. Have to give it credit that is impressive dedication to mild.

[Scott Ingham]

Just now, mountain shadow said:

Next week doesn't look anything special snow wise at all now away from the North East.

Bits of snow here and there then a quick return to wet and windy with some transient snow as the mild moves back in.

Still time for change of course, but it all looks a bit meh to me despite the positivity of the background teleconnections. 

Snow can’t be forecast until 48hours before the models don’t have the resolution to pick up disturbances so to say it’s dry now is a lesson we learnt years ago in these spells. Best bet is your hi res models 48hours out

[Captain Shortwave]

I will say the trend for week 2 could potentially be a flip from quite notable cold to potentially quite notable mildness as the pattern seems to want to develop a broad west to south west flow with heights building over south west Europe. However this is at a timeframe where potential wedges of heights will not be reliably picked up. I will add that even if conditions do go mild, it is purely because the long wave pattern is favouring this, rather than the polar vortex is recovering, as such a flip to cold again is quite probable and of course the mild might not even happen.

[Metwatch]

12 minutes ago, Scott Ingham said:

The issue with frontal clashes is it tends to be a day of snow then mild air coming in 48 hours later. I prefer to keep the cold in and get several troughs shortwaves in a flow for a week or two. But each. To their own I guess!

Some cases yes, not always though. It does seem to be less often these days compared to more severe winters where frontal clashes would bring the snow, then the cold would come back in for a longer period and so you get those brutally cold nights over that snowcover. For me I hate longer cold spells when not much snow is brought in, especially the case with faux cold spells but other cases here i.e December 2022, so something like December 2017 or 24th January 2021 is ideal but again not for everyone. Jan 2010 / December 2010 is best for almost everyone, but I wouldn't say a repeat of that is set in stone. A lot of lmbyism there but it is what it is...

I'm still thinking less cold air arrives from the west (maybe not for long) from next weekend based on current model data despite the background signals showing it to not exactly do so? Sooner get the snow the better with the upcoming spell. More opportunites to come with more widespread snow events rest of this month if we get those wedges and sliding lows, I am fairly confident with sticking my neck out with that.

Edited January 11 by Metwatch

[Sweatyman]

1 minute ago, Tim Bland said:

ECM is worst case scenario for the south if it’s snow you’re after. South of Birmingham it delivers almost nothing. The north get a couple of days of snow cover end of the week before it warms up  

it's a rubbish run from Brum south. i want JMA all day long!

[SilverWolf]

1 minute ago, Scott Ingham said:

Snow can’t be forecast until 48hours before the models don’t have the resolution to pick up disturbances so to say it’s dry now is a lesson we learnt years ago in these spells. Best bet is your hi res models 48hours out

Not nationwide, but the fairly substantial snow I had in Dec 22 wasn’t predicted 12 hours before! I’ll always remember that when scenarios like next week are probably upcoming…