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

[Stephen W]

I don’t think I was quite expecting such an exceptionally mild looking set of charts to appear in the model output as is currently showing for next week. And there is nothing indicating at the moment that won’t be for an extended period, ie 10 days + (waxing and waning a bit). I take note and value those more knowledgeable members who are confident of a more blocked and cold pattern re-emerging end Jan into Feb. I do hope we get something of more note than this upcoming week before winter is out.  At the moment, I’m looking at these charts and thinking they look all too familiar (not favourable to coldies) despite the favourable background signals that many have been discussing.

Still, we should enjoy the short lived cold spell this week and the break from all that rain and some will no doubt be posting some wonderful winter photos that many of us will, sadly,  have to enjoy vicariously.

[kold weather]

Ensembles from all models continue to suggest that the south do need to keep a watching brief over the midweek frontal zone. 

Broadly seems to.be about 20% on most suites, with maybe another 20% very close or just touching the south coast.

Itsenough odds that it needs to be watched still because there are some very high impact scenarios on there (some go to 20cms for example).

[stodge]

3 minutes ago, LRD said:

This is what EC46 was showing (pressure anomaly-wise) this time last week for week of 22 Jan

Not bad that far out. For a week, the evidence has been there that next week will be much warmer than this.

No denying that this week will be another load of 'meh' in many central and southern areas and looks like another pretty boring cold spell. I sense that frustration on here and people are lashing out a bit

Yes, the next pattern change to a westerly-based regime was and has been well signalled and those hoping for some continuation of the cold were really clutching at the flimmiest of straws.

As to the week beginning 22nd, mild or very mild conditions but much windier and probably dry for much of the south of Britain. Further north, a likelihood of rain though not in large quantities but again probably strong winds the main feature.

At the end of the month, who knows? It's far too early to come up with ludicrous assertion that the chances of lowland snow have gone - there's the small matters of February and March both of which (oddly enough more the latter than the former) can deliver snow for many. On a personal note, we are overdue a traditional cold February - will 2024 be one?

[bluearmy]

14 minutes ago, CoventryWeather said:

Seen a number of models shift Tuesday's Low southwards - nearly 100miles on the latest ICON, ECM also follows it. 

Some on the ECM/GEFS06z had it as far south as North Wales, so clearly another feature yet to be nailed. Expecting a further shift in this over the next day. 

Not really seeing much adjustment through todays runs 

looks to come in through the isle of arran and exit N of the Humber 

I think that’s been a fairly consistent passage over the last few days modelling. Agree if there has been any adjustment over the past five days then it’s south but annoyingly the nwp has done a good job on this shortwave 

 

 

[Stephen W]

4 minutes ago, stodge said:

Yes, the next pattern change to a westerly-based regime was and has been well signalled and those hoping for some continuation of the cold were really clutching at the flimmiest of straws.

 

I don’t think a continuation of the cold was necessarily expected but neither are the exceptionally mild charts currently being shown in the model output. What many were thinking is that the breakdown would not be as abrupt and would potentially offer a slower and possibly snowier transition to less cold conditions.

[LRD]

3 minutes ago, Stephen W said:

I don’t think a continuation of the cold was necessarily expected but neither are the exceptionally mild charts currently being shown in the model output. What many were thinking is that the breakdown would not be as abrupt and would potentially offer a slower and possibly snowier transition to less cold conditions.

A) the very mild charts might not come off

B) does it even matter if ends up being mild or very mild. It's still mild!

I never sensed any real prospect of a snowy transition but, you're right, some did. The evidence was never really, consistently there though

[Met4Cast]

 

Difficult to argue against the signal for milder & unsettled weather looking at the ensembles but the longer term prospects still favour a return to cold/blocked patterns. 

Edited January 14 by Cambrian

[Paul]

All posts are being pre checked by the team currently. It's a temporary change 

[JimBob]

2 minutes ago, LRD said:

A) the very mild charts might not come off

B) does it even matter if ends up being mild or very mild. It's still mild!

I never sensed any real prospect of a snowy transition but, you're right, some did. The evidence was never really, consistently there though

The mild charts always come off as the Atlantic is our default weather pattern! 

[AO-]

5 minutes ago, Met4Cast said:

 

Anyway - Difficult to argue against the signal for milder & unsettled weather looking at the ensembles but the longer term prospects still favour a return to cold/blocked patterns. 

I am affraid that the blocked pattern might as well be a Euro block with a Westerly flow into Scandinavia. A pattern that I have seen a lot the last few years with 2020 as a perfect example. 

Edited January 14 by Cambrian

[January Snowstorm]

The ecm @ 216hrs shows a very mild flow over the UK and Ireland. It really will be quite the change after this weeks cold spell. We have come accustomed to temps of 3 to 6, anything up around 13 or 14C really will feel very mild!

[LRD]

7 minutes ago, JimBob said:

The mild charts always come off as the Atlantic is our default weather pattern! 

I said the VERY mild charts might not come off

I realise it's going to turn warmer week of 22nd. I've been saying that warmer conditions looked on the cards since last week. I'm just putting it out there that the EXCEPTIONALLY mild stuff some models are showing might not come off.

But, as I say, mild is mild! 9C and 14C - all the same to me!

Edited January 14 by LRD
Typo

[legritter]

Hi gang , realy enjoying your posts , thanks to all those who post interesting charts etc .The outlook for 140 hours time is a kick in the Baps , but still loads of time for something cold and snowy , cheers gang .

 

[AO-]

Sorry to be posting EPSs for my location, but nevertheless I hope it is insightful. The latest EPS shows that we must be keeping aan eye on the 27-28th. I am not sure about the synoptics, but colder members come into play by then. Hope they will be increasing by number in the coming days and that it is a start of a cold February.

 

Edited January 14 by AO-

[LRD]

28 minutes ago, stodge said:

Yes, the next pattern change to a westerly-based regime was and has been well signalled and those hoping for some continuation of the cold were really clutching at the flimmiest of straws.

As to the week beginning 22nd, mild or very mild conditions but much windier and probably dry for much of the south of Britain. Further north, a likelihood of rain though not in large quantities but again probably strong winds the main feature.

At the end of the month, who knows? It's far too early to come up with ludicrous assertion that the chances of lowland snow have gone - there's the small matters of February and March both of which (oddly enough more the latter than the former) can deliver snow for many. On a personal note, we are overdue a traditional cold February - will 2024 be one?

Yes, good points

I am getting a feeling of 2019 at the moment. There was a projected cold spell in Jan of that year that looked like it had potential to become quite severe. That ended in a bit of a damp squib and the prospects of a SSW looked promising for Feb. We all know how that turned out. What was it... 19C/20C right near the end of Feb '19? Remarkable warmth

However, a cold, wintry Feb certainly feels possible at this point in time, although EC46 has backed off that further tonight with high pressure over or very near us looking favoured. It will change, I expect

Feb charts. Week of 5th:

Week of 12th:

 

[Dunstable Snow]

I’ve been following and reading all the posts over the last few weeks. It’s been terrific to follow and a lot of the contributions have been of a really high quality. 
 

Things don’t appear to have fallen our way and if you go back and read the threads there have been some key moments which have highlighted the fact that we could well end up and indeed were likely to be disappointed not withstanding deterministic outputs. 
 

We will end up with two weeks of cool, cold and very cold weather pretty much looking at the latest models and that has been very well signposted by knowledgeable, experienced posters on here. 

The situation can and does change quickly and I am very hopeful that the next chase will be underway by this time next week. 
 

it’s a bit like Fulham getting into the top eight of the Premier League. Unlikely to happen and if it does it’s fleeting and to be enjoyed because the inevitable knock backs and return to normal soon follow.

[MJB]

Not a huge fan of these charts but I'd take that if F&F can be produced 

Let's see where we sit come the 5th

[Paul]

29 minutes ago, Paul said:

All posts are being pre checked by the team currently. It's a temporary change 

We're back to normal now. It's important everyone makes an effort to stay on topic and within the community guidelines from here on in though. 

[bluearmy]

8 minutes ago, LRD said:

Yes, good points

I am getting a feeling of 2019 at the moment. There was a projected cold spell in Jan of that year that looked like it had potential to become quite severe. That ended in a bit of a damp squib and the prospects of a SSW looked promising for Feb. We all know how that turned out. What was it... 19C/20C right near the end of Feb '19? Remarkable warmth

However, a cold, wintry Feb certainly feels possible at this point in time, although EC46 has backed off that further tonight with high pressure over or very near us looking favoured. It will change, I expect

Feb charts. Week of 5th:

Week of 12th:

 

Whilst the ec46 no longer shows the cold set ups it was doing for feb up until a week ago, it continues to show high anomalies close to nw europe and we know it won’t be accurate. (So perhaps move those anomolies around a bit). If it was showing a climatological average zonal flat westerly with +nao then we’d be wondering what it was seeing next month when set against expectations 

[Singularity]

IMO it’ll be worth keeping an eye out for any adjustments toward a more northward direction of travel for the big surge of very mild air being modelled the week after this coming one. That would serve as a trigger for shifting high pressure fully northward through the UK.

I only flag this due to the expected AAM/MJO situation not really being conducive to a massively pumped up high centred south of the UK (such would be fitting if AAM was a lot lower). In other words, it’ll take a lot to force such an outcome rather than open a path for northward migration of the high at some point during that week.

[iowpompeylee]

Looking at the latest Met Office fax chart for Wednesday surely that will clip the south coast? That has to completely drop like a stone to miss us all. Think tomorrow’s run will nail it one way or another 

[Mike Poole]

34 minutes ago, LRD said:

Yes, good points

I am getting a feeling of 2019 at the moment. There was a projected cold spell in Jan of that year that looked like it had potential to become quite severe. That ended in a bit of a damp squib and the prospects of a SSW looked promising for Feb. We all know how that turned out. What was it... 19C/20C right near the end of Feb '19? Remarkable warmth

However, a cold, wintry Feb certainly feels possible at this point in time, although EC46 has backed off that further tonight with high pressure over or very near us looking favoured. It will change, I expect

Feb charts. Week of 5th:

Week of 12th:

 

Yes, the 46 signal for February has been eroding a bit lately.  I’m not as bullish about the February cold spell yet as I was about the current one.  Don’t want to put too much store in the 46 because I don’t rate it, but one component of the idea of increased blocking potential is a decent amplitude MJO through into the favourable phases, and what is the 46 seeing:

The moment it gets to phase 7 it goes directly to the COD without passing ‘go’ or collecting £200!  We need to keep our eye on this, it may be just the vagaries of the 46, of course, but I think we do need at least some contribution from the MJO to break out of this upcoming zonal spell.

On the other hand the seasonal models bode well for February:

Particularly strong signal on GloSea6, JMA and Meteo France, one proviso with those is they were run on or before 1 Jan, and we’ve had developments in the strat since then.

Clusters zonal out for the foreseeable, T264+:

Cluster 3 has a reasonable stab at a Scandi high, and 4 looks interested too - but note that this is at odds with the 46 and the seasonals which suggest heights would build to the NW not NE if anything.  

So a lot of uncertainty, hopefully some of this will become clearer soon, along with - well I won’t say fallout from the SSW (as will be one in name only as @bluearmy post earlier illustrated clearly) - further developments in the strat, shall we say.  But at the moment I’m not going to be ramping February.  

 

Edited January 14 by Mike Poole

[Man With Beard]

58 minutes ago, kold weather said:

Ensembles from all models continue to suggest that the south do need to keep a watching brief over the midweek frontal zone. 

Broadly seems to.be about 20% on most suites, with maybe another 20% very close or just touching the south coast.

Itsenough odds that it needs to be watched still because there are some very high impact scenarios on there (some go to 20cms for example).

I made it 18 out of 51 ensemble members on the ECM 12Z that would likely lead to a covering of snow for the southern most counties (I didn't include the op or control as they generally returned less than 1cm). That's the most members for a couple of days. And yes, as you mention, there's the outside chance of a significant fall.

[johncam]

23 minutes ago, LRD said:

Yes, good points

I am getting a feeling of 2019 at the moment. There was a projected cold spell in Jan of that year that looked like it had potential to become quite severe. That ended in a bit of a damp squib and the prospects of a SSW looked promising for Feb. We all know how that turned out. What was it... 19C/20C right near the end of Feb '19? Remarkable warmth

However, a cold, wintry Feb certainly feels possible at this point in time, although EC46 has backed off that further tonight with high pressure over or very near us looking favoured. It will change, I expect

Feb charts. Week of 5th:

Week of 12th:

 

Looks very similar to what has just happened/happening 

[Downburst]

1 hour ago, MJB said:

Chocolate teapot and are taken from the 0z run, only really accurate a week out...............at best 

We’ll have to disagree on that I’m afraid. That’s totally fine of course. They are a weekly mean also, so one has to watch the trend and understand in the case I used that’s surface pressure anomaly. I’ll let ecmwf know your review.