Model output discussion - after the beast, what next?

[stodge]

1 hour ago, Mike Poole said:

It's difficult to know what to say this evening. Yesterday the models were split between cold north of easterlies, and south of easterlies and it is a massive difference for the UK at this time of year. Easterlies it  look like we are going to get but ECM (here at T192) supports earlier model output for the warmer option

This is why I enjoy looking at the models at this time of the year. The synoptic evolutions on offer are many and varied and some look completely improbable. That being said, the GEFS 12Z is actually more solid for northern blocking than the 00Z:

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=240

A strong cluster of members holding heights to the north or north east by this time and with the European trough weaker and less defined the air flow is more south east than east drawing up warmer air. I see a more notable signal for blocking from Greenland at the very edge of FI past the middle of the month.

It's possible we could have a warmer spell before the middle of the month before it turns cooler again further on - at this time of year, almost anything is possible. 

[Frosty.]

Tonight's Ecm 12z ensemble mean shows we are about to scoop up some warmer air sourced from southern europe during the next few days with temps in favoured spots further s / se hitting the low to mid 60's F and even beyond the weekend there is no sign of a return to the unseasonably cold weather that we have seen so much of so far this spring, indeed on the whole it stays on the mild side and feeling warm in the sunshine but it's not a settled outlook, with trough influence continuing at least into the first part of next week there is likely to be some rain / showers at times but with high pressure persisting to the E / NE the atlantic systems are held at bay or even pushed back further which is still the situation by day 10..so, it's not perfect by any means but at least it's more spring-like!? 

[Summer Sun]

Plenty of mild air on this mornings 00z ECM temps in the east are likely to be tampered by the north sea at times but with some shelter, in the west, the mid to upper teens is more than possible

[Frosty.]

Starting with some good news, today could be the warmest day of the year so far if temperatures reach 17c across the SE (london) is the favoured spot.

The Ecm 00z op pretty much follows what I posted last night about the Ecm 12z ensemble mean with the emphasis on spring-like temperatures whereas the Gfs 00z turns colder for a time later next week, especially further north.

This weekend it's hit and miss regarding warmth with warm uppers bathing the uk but where there's cloud and rain it will feel cold but where it's dry with sunny spells, temps could reach 18c 64f (again it's the SE most favoured) which would feel very nice indeed..the Ecm 00z ends very positively with the azores high ridging in and heights persisting to the NE .? 

Edited April 6, 2018 by Frosty.

[stodge]

Morning all

Am I going to be first up on the morning output ? Certainly plenty of interest yesterday with the previously firm-looking easterly for next week starting to be challenged in some of the OP models by a resurgent Atlantic but heights never far away from the NE or NW suggesting the strength and direction of any Atlantic push was far from defined at this time.

This morning's medium term analysis takes us to Monday April 16th so just into the second half of the month and we'll start with the ECM 00Z OP at T+240:

A messy evolution but the key features are the trough over Europe and heights over Scandinavia. This morning the former is proving more resilient than the latter which is the reverse of yesterday. BY this time the HP has declined SE with a weak residual ridge over Scandinavia linking back SW to a ridge building through the west of the British Isles from the Azores. Southern and Eastern areas are nearer the weak LP over Europe and there is a slack NE'ly in place with a risk of showers for these areas while most of the rest of us enjoy fine conditions. A developing Atlantic LP is moving slowly NE well to the west but it's too early to be sure how that will play.

GEM 00Z OP at T+240:

A little different from ECM. There's a pattern of heights to the NE and small Atlantic features disrupting SE to the west of the British Isles and ending up over western Europe and by T+240 we have a significant LP centred over northern Italy with the trough aligned back NW across southern Britain bringing plenty of rain or showers for southern and western parts. Further north, the east coast is plagued by an ESE'ly air flow sourced from Turkey so not cold but probably picking up plenty of sea fog crossing the North Sea so the coasts dull but to the western side decent conditions and a good time for that Hebridean break you've always promised yourself. Not quite sure how we break this pattern at this time with the trough lying through the southern parts of Britain.

GFS 00Z OP at T+240:

GFS throws spring a real curveball this morning to use an American expression by dishing up a cold run. The key differences are the role of Greenland heights rather than Scandinavian heights and the trough extends out into the Atlantic to the south of Britain. Next week looks particularly bracing along the east coast and the theme continues by T+240 albeit with a slacker flow. The 850s aren't bad but nothing very spring like, Further into FI, the air flow gets a more southerly tilt as the Atlantic LP tries to fight its way in against the strong northern blocking.

GFS 00Z Control at T+240:

We catch the HP in mid retrogression from Scandinavia to Greenland and the air flow is a warmer ESE'ly but rain or showers for southern and western parts close to the European trough. Further into FI and little changes with the Atlantic moribund and northern blocking in charge. Plenty of cold air building to the east and north east so spring still very much on hold.

The GEFS 00Z at T+240:

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=240

With the OP and Control leading the way and supported by the Mean, there are no surprises the easterly outlook, after yesterday's wobble, is firmly in charge with the GFS. Northern blocking rules, mainly from Scandinavia or to the north of the British Isles and while there are variations over the orientation of the HP and the trough, the signal for some form of easterly is clear.

Moving further on and entering the last third of the month, a strong signal for blocking to transfer to Greenland. That doesn't necessarily mean a cold Arctic blast though if P14 verified we'll all be looking for our thermals. A number of the Members have the LP more or less over the British Isles with the coldest air deflected to the west while others modify the NE flow by having the HP close to the north west coast of Scotland. There is no signal for MLB to the east or for heights to the south.

In conclusion, I said "game, set and match" to the easterly earlier in the week but there was a wobble of sorts yesterday but this morning GFS has clearly and unequivocally backed it with northern blocking likely to dominate for much of the month. GEM and ECM are more equivocal - yes, next week looks to be dominated by air from the east or south east but both models have signs of an awakening Atlantic around mid month. To be fair, GEM has a disrupting trough pattern which could simply continue so ECM looks the most positive if you want a break from the easterly but GFS looks to have it locked in for a fortnight.

To be fair, easterlies in April aren't unknown and given what has happened this late winter and early spring the likelihood was almost certainly increased. Nobody's talking Beast 3.0 or whatever - indeed, with good fortune, it might be reasonably warm at times and for those in north-west Scotland who often get the rough end of the deal, there could be some excellent weather to be had if the cards drop right. For southern and eastern Britain, however, it doesn't look promising with the coasts troubled by sea fog and rain or showers never far away thanks to the persistent trough over western and central Europe.

[stodge]

Strange how some only want to comment on one model for some reason but that's their prerogative. Across the model suite, the easterly now seems confirmed:

Nothing cold about that but unsettled especially for southern areas with rain or showers likely from the LP in Biscay - could there be a storm or two in that mix ? Maybe as there is some warmer air to the east the moisture could engage - one to note.

[Man With Beard]

I think I've made a bit of a mistake with my recent analysis of the upcoming situation. I've only had time to look briefly at 500mb charts in the past few days and I've missed the fact that the UK is set to be a boundary point between easterly sourced and westerly sourced air. As a result, there looks set to be a lot of precipitation next week. This is GFS 00Z rain totals by D7 - ECM 00Z rain totals are broadly similar though slightly different in locations:

So on this morning's charts, actually a pretty wet week coming up in central/western areas of England and Wales, with 3 inches quite possible in places. Both western/eastern coasts (except NE), as well as Scotland, look set to avoid much of the rain.

Best places for a late Easter break look to be E Anglia, Scotland and the Lake District. In fact the ECM has quite a warm week in inland parts of E Anglia.

It doesn't look particularly cold anywhere next week except on days where areas are stuck under persistent rain.

Further ahead, both GEFS and ECM ens generally want to keep heights slightly to the N or E - in theory this should mean continental weather for the UK and therefore quite dry (and potentially warm by mid-April) - but as we're probably going to see in the next week, if the block is slightly less influential over the UK, then the UK can be left in a wet slot.

 

[stodge]

4 minutes ago, Man With Beard said:

So on this morning's charts, actually a pretty wet week coming up in central/western areas of England and Wales, with 3 inches quite possible in places. Both western/eastern coasts (except NE), as well as Scotland, look set to avoid much of the rain.

Do you think the large inland figures could be from convection in the form of showers or storms ? The wind blows on to the east coast and meets the warm air rising off the land forming heavy and possibly thundery showers.

I though the far NW of Scotland would do better but as you say the influence of HP and positioning of the trough aren't resolved yet. IF the trough stays close to the south, then more rain is the only call but ease that south and have the HP closer to the north and it would be more settled.

[Man With Beard]

3 minutes ago, stodge said:

Do you think the large inland figures could be from convection in the form of showers or storms ? The wind blows on to the east coast and meets the warm air rising off the land forming heavy and possibly thundery showers.

I though the far NW of Scotland would do better but as you say the influence of HP and positioning of the trough aren't resolved yet. IF the trough stays close to the south, then more rain is the only call but ease that south and have the HP closer to the north and it would be more settled.

Yes I think so - April showers, and bad ones by the looks of it

[Jonathan Rhodri Roberts]

6 minutes ago, Man With Beard said:

I think I've made a bit of a mistake with my recent analysis of the upcoming situation. I've only had time to look briefly at 500mb charts in the past few days and I've missed the fact that the UK is set to be a boundary point between easterly sourced and westerly sourced air. As a result, there looks set to be a lot of precipitation next week. This is GFS 00Z rain totals by D7 - ECM 00Z rain totals are broadly similar though slightly different in locations:

So on this morning's charts, actually a pretty wet week coming up in central/western areas of England and Wales, with 3 inches quite possible in places. Both western/eastern coasts (except NE), as well as Scotland, look set to avoid much of the rain.

Best places for a late Easter break look to be E Anglia, Scotland and the Lake District. In fact the ECM has quite a warm week in inland parts of E Anglia.

It doesn't look particularly cold anywhere next week except on days where areas are stuck under persistent rain.

Further ahead, both GEFS and ECM ens generally want to keep heights slightly to the N or E - in theory this should mean continental weather for the UK and therefore quite dry (and potentially warm by mid-April) - but as we're probably going to see in the next week, if the block is slightly less influential over the UK, then the UK can be left in a wet slot.

 

To be honest after last week's very wet weather in south Wales with some flooding in Pembrokeshire, that chart is actually looking much drier, especially around the coasts giving an indication that most of the rain/showers will be inland probably due to surface heating whereas the sea is colder than average so far this April. 

[Frosty.]

The Gfs 6z operational run really perks up through low res with high pressure and pleasant warmth developing nationwide..that would be lovely during the second half of april..I think most would agree!?

[Frosty.]

There's certainly some support for the Gfs 6z op for a pleasant anticyclonic spell around or just beyond mid month from the Gefs 6z..fingers crossed!?

[Summer Sun]

What a difference 6hrs makes 

06z GFS

12z GFS

Edited April 6, 2018 by Summer Sun

[Summer Sun]

Nice turn around from GFS this afternoon

Hope this continues  

[Summer Sun]

It looks like the warmth will be really building for the likes of Germany and Poland next week with the right set up we could easily tap into that later next week as hinted at above

[Summer Sun]

A coldies special to end the 12z

[OldBloke]

I wouldn't be surprised if the east side of the UK from about the Wash northwards gets a little bit of the white stuff next week.

[Ice Man 85]

1 hour ago, Summer Sun said:

Nice turn around from GFS this afternoon

Hope this continues  

Well these are the TWO charts for the same run:

So someone's got their wires crossed.

Edited April 6, 2018 by Ice Man 85
more to add

[Frosty.]

2 minutes ago, Ice Man 85 said:

Well these are the TWO charts for the same run:

So someone's got their wires crossed.

Yes you have, Gavin's charts are 3pm (warmest part of the day) and yours are 6pm which is why the temperatures are lower on yours!!

[Ice Man 85]

9 minutes ago, Frosty. said:

Yes you have, Gavin's charts are 3pm (warmest part of the day) and yours are 6pm which is why the temperatures are lower on yours!!

Sorry to disappoint you: Still different. Might want to check the GEFS too. not one member shows anything like the netweather saturday chart and the sunday chart has a whopping 10% support!

 

Edited April 6, 2018 by Ice Man 85
more to add

[Frosty.]

5 minutes ago, Ice Man 85 said:

Sorry to disappoint you: Still different.

 

netweather charts are better / higher resolution..does that answer your question now?

[Ice Man 85]

1 minute ago, Frosty. said:

netweather charts are better / higher resolution..does that answer your question now?

Meteociel also disagrees. netweather doesn't show the entire suite. cherrypick all you want.

[Summer Sun]

11 minutes ago, Ice Man 85 said:

Meteociel also disagrees. netweather doesn't show the entire suite. cherrypick all you want.

Sorry to disappoint you but it does agree with netweather

Edited April 6, 2018 by Summer Sun

[Ice Man 85]

1 minute ago, Summer Sun said:

Sorry to disappoint you but it does agree with netweather

only one of them. when you have 3 different charts from the same run, whose to say which one is right? guess old brian best stop posting model outputs then, eh?

[Mike Poole]

Odd discussion in here tonight.  The different websites that produce charts of model output will have different resolution, different colours etc.  My advice would be to find a site that suits you and stick to it.  Personally, I prefer Meteociel, because it has charts from so many models, plus reanalysis charts using the same graphics, and because use of the full colour spectrum rather than just pastal shades makes the charts much easier to read.  But that's just my personal preference.

Anyway, how's the ECM shaping up?  T168

Going for the warmer evolution, that's not to say it will be dry!

Edited April 6, 2018 by Mike Poole