[Model Output Discussion - Spring Has Sprung]

Are we finally heading towards the promised land? As in, a U.K. high? The ensembles certainly think so.

GEFS

GEPS

I’m not going to fret about random GFS Ops progging the big Greenland high. As long as the means stay solid on the U.K. high, we’re all good.

[Model Output Discussion - Spring Has Sprung]

 Rain All Night good spot on the 6z GEFS. Along with the op, it’s the best ensemble set for U.K. high pressure I’ve seen since the January spell (ie the ‘last’ spell )

But, as @johnholmes wisely points out, we need a few days of this sort of U.K. high type output to have any confidence that it’s a trend and not a whim.

Given the tendency the modelling has had to underestimate the flatness of the pattern since last June, I remain highly sceptical of any pattern change - especially up here in the nw; things do look more optimistic for the se. That said, it has to happen sometime and - if the last decade is anything to go by - maybe when it’s stops, it’ll stop if you know what I mean. When the 19/20 barrage ended we went dry for ages. Similarly after the horrors of the 15/16 winter 16/17 had many a long dry period. Long wet spells have generally given way, after 6-9 months, to a drier trend. Especially, like now, after a Nino has faded.

Perhaps the latest ec seasonal - with a +nao and heights close to the U.K. might be suggestive of better things to come in the summer.

Indeed, most seasonal output does seem to be suggesting a +nao and thus the possibility of a warmer, drier summer.

We can’t say we haven’t earned it.

[Model Output Discussion - Spring Has Sprung]

 In Absence of True Seasons absolutely agree mate

 Summer8906 I think the high solar, Atlantic SSTs, the ssw and plain bad luck are driving the continuation. One sure thing about luck is it has to change but the first two aren’t anytime soon. You wouldn’t have thought a quick / rapid transition to a Nina will help either. Maybe the return to a period of relative SPV strength might shake things up. I hate west based -nao more than any other pattern, apart from the dec 2015 pattern. We haven’t had a scandi high that has affected us positively since June. We’ve had about 15 pointless Greenland wedges in that time and all we get are a U.K. low or back door southwesterlies. Regardless, having 10 wetter than average months in a row really would be something. Imagine if it was the other way round? I still think that when it flips it flips these days. I just still can’t see any sign of it happening.

[Model Output Discussion - Spring Has Sprung]

I’m not sure I’ve ever seen so many euro areas this wet before on a 10 day op, gem:

On that chart, only really the western Czech Republic looks dry. 

Fwiw, the gfs seems to apparate a wedge of heights in the extended.

Not very well supported by the ensembles, who continue to indicate a low sandwiched between a west based -nao and a se euro high. Not a pleasant combination and one that we appear to be getting so often recently.

I’m not sure what weather enthusiast could get enthusiastic about that pattern. I realise some people like rain, especially after a dry period. But not after 10 months surely. Everything is just so damp. And boring.

I’m searching hard for signs of drier, sunnier weather. When I find it, you’ll be the first to know.

 

[Model Output Discussion - Spring Has Sprung]

Both gem and ec Ops going down the big block to the nw scenario

Both still manage to be wet though (obviously).

As has been the case for, well, ever, it’s too far Nw to actually bring a cold Ne type instead we get trapped between that high and the ever present se euro high. Something about the Atlantic / solar / SST global setup must be stacking the cards in favour of this kind of blocking. It’s completely useless for us unless you like above average cloud, rain and moaning on this thread.
 

I have found a little smidgen of hope/cope on the GEFS.

Dry weather / spring could be a mere 300 hours away.

If I was a squirrel I would carry on hibernating till then.

[Model Output Discussion - Spring Has Sprung]

Is there light at the end of the tunnel / gutter? 
 

Some signs in the extended range of a post-Easter switch in weather type with more influence from high pressure.

Ec clusters

3 reds at the final step.

GEFS extended is nondescript , but no obvious low…

GEPS has more of a high to the NW

Would still most likely be drier than what we’ve had (not hard). Grey in the east maybe. But still the drier theme.

The mjo also now progged to move quite strongly into phase 8/1

The strong phase 6  -where we’ve been -surely has a part to play in the coming Atlantic /  U.K. trough

Then there’s the downwelling waves from ssw #426. Though to be honest, getting excited about the strat ain’t what it used to be after this winter.

Still, it’s still very reversed, so you would think the easterlies will take over eventually. 

I maintain my belief that the pattern will flip at some point. Hopefully for good and we can revert to a more Nina driven drier trend.
 

This has been a coruscating 9 months - relentless in its miserableness. When the next U.K. high does eventually settle in. Take a moment to appreciate it. 
Thanks 

Josh

[Model Output Discussion - Spring Has Sprung]

 stodge interestingly the op could have been a trendsetter, the mean has strongly moved towards it:

144 current 

168 yesterday 

More of an influence from scandi and a brief easterly, rather than the negatively tilted trough and nw winds.

The mean still gets the Atlantic again eventually; it’s more of a delay. Interesting nonetheless. Perhaps the ssw / WP mjo finally starting to show its hand. Let’s see where we’re at tomorrow.

[Model Output Discussion - Spring Has Sprung]

1% chance: The ec op has spotted a new signal

99% chance: every other model / ensemble

This winter has taught me what I already knew: op runs are simply single perturbations - if they fly in the face of consistent means, then they’re for the

Will the ec op be right then?
I’ll let you decide…

[Model Output Discussion - Spring Has Sprung]

 Rain All Night it’s basically a U.K. low taking the best part of a week to fill. Horrific for crops and yields nationwide.

Probably to be replaced or superseded by another one. God what I’d give for a 2018 or 2022 summer now. On that note my initial analysis hints at a reasonable summer - in the se especially - so maybe not bad for you mate. Long way off mind. We’ve had 2 one week U.K. highs in 9 months (sept and Jan). We need one asap. AI model has this in goo goo land.

Bank?

[Model Output Discussion - Spring Has Sprung]

A predictably pathetic climb down from the gfs. Run after run it has produced a phantom block giving chilly easterlies but we all know what we’re going to get is U.K. low number 353 since last July.

Even the icon gave up the nonsense earlier.

Last run

What we’re actually going to get is something like this monstrosity

I mean come on. What is that? 
 

Save us, La Niña.

[Model Output Discussion - Spring Has Sprung]

Not seeing this phantom U.K. high coming to anything. The last 9 months have seen the U.K. become a beacon of low pressure, rain and gloom. The eps and geps have sacked off any hopes of a meaningful pressure rise. Even a split ssw and high amp mjo into the pacific doesn’t matter anymore. 
 

Im sure it’ll flip eventually, but this is one of my least favourite periods of weather. Always the promise of interesting, settled or cold weather but the reality has been utterly grim. 

[Model Output Discussion - Spring Has Sprung]

 Met4Cast there have been enough ops recently having a go at the cold pool to view it as a feasible option. However,  the blown up trough is probably more likely given recent form - we have really struggled to get lows to undercut in recent years. Need to see that cluster disappear and full model agreement to start even thinking about looking at the cold pool / dew points / precip intensity etc. The ecm op solution nearly goes belly up and then rescues it at day 9/10 - that’s light years away in modelling terms. The UKMO gets there quicker but I’m not convinced it would be particularly snowy.

 

There has been a shift in the forecast for beyond day 10 today, yesterday the models wanted to barrel the Atlantic back, today the high looks more resilient. Plenty of twists and turns to come but personally the excitement has ebbed away for me after the Jan / Feb forecast fiasco.

[Model Output Discussion - Spring Has Sprung]

The upcoming trough disruption against rising heights to the NE is a scenario the modelling typically struggles with. Whilst this time round is no different, the ensembles have actually been rather consistent with their idea of a negatively titled trough and the U.K. in a se wind on the periphery of the high. However, this does feel like one of the few scenarios where upgrades to the strength of the high to the Ne are plausible. 
 

So here’s the UKMO, minibeast?

GEM also has an upgraded scandi high

leaving the gfs continuing  with its encroaching sw low?

The gfs represents the last few days mean pretty well, but the others are the upgrade paths that seem increasingly plausible.

[Model Output Discussion - Spring Has Sprung]

@IDOyou’re absolutely right mate. A se flow, potentially more low pressure dominated than high does seem the form horse on the means. Only reason I wouldn’t rule out something akin to the ec op is the big reversal plus, of course, the irony of avoiding cold Synoptics till after winters finishes. 
 

The op cluster has 8 members so less than 20%. I actually think that’s about right for the probability of a cold long fetch easterly amidst a -15m/s protracted reversal / potentially unfavourable mjo phase. 

[Model Output Discussion - Spring Has Sprung]

Stunning chart!

[Model Output Discussion - Spring Has Sprung]

I am very wary about modelled scandi highs, they tend to be fictitious. However, the one developing next week does seem likely but there are still question marks around its influence over the U.K.s surface conditions. The trend today has been to have it more influential, bringing a very welcome drier trend. Even the gem, which has been annoyingly consistently unsettled has started to entertain the possibility of the scandi high exerting more influence.

But, it could very easily shift back to being a hindrance to such a trend by manifesting too far eastward and allowing a trough to stall up against it - one of the autumn storms did that and brought some severe rainfall totals to eastern Scotland. We don’t need any more storms or stuck fronts.

Beyond that the gfs and, were it to continue, the ecm, suggest a colder pattern could establish with some retrogression and the transport of a cold pool.
 

Ec day 10

Gfs day 12

At this stage, such an evolution is highly fanciful and would require thread the needle style synoptics to force a snowy March scenario. A watching brief then.

On a purely anecdotal note, my own observations tend to gauge these persistent wet spells as generally 6-9 month iterations. The current deluge began with the weekends of July 2023 and has continued ever since - broken only by the Sept and Jan short high pressure visits. The last such super wet spell we had was July 2019 - March 2020. A very dry period followed and broadly continued to June 23. Previous to that it was, with a similar timeframe, in 2015-16. Again we were drier rather than wetter after that. Given we once again have a La Niña on the horizon one would hope that the current now 8 month super wet spell should hopefully come to an end soon and we could have a more generally drier long term period ahead. 

[Model Output Discussion - Spring Has Sprung]

The JMA shows we can still roll snake eyes and end up with this monstrosity:

The ecm op - which over the past few years I have grown to have little faith in - almost makes it with the heights over the top ridging to scandi but, alas, fails miserably. Still, the day 10 chart looks - as well as looking a lot like the strat output - more like the start of something than the end…

 

[Model Output Discussion - Spring Has Sprung]

The track of next weekend’s Atlantic shortwave - diving into the base of the already established long wave trough -and upstream amplification, is certainly of interest this evening. Though we’re still at the stage where the modelling is envisaging it in many different ways…
 

Ukmo

The UKMO barely develops it at all and thus the Atlantic ridge is able to push north

 

Icon

The German model does develop the low, but it stays on a thoroughly NW/SE track and the  Atlantic high pushes north anyway

Gfs

Similar to the UKMO, barely develops the shortwave. The northern arm Of the jet really stretches itself polewards on this run. Will need a lot more runs to convince me of this, but there’s clearly a trend here…

 

Gem

The gem does develop the shortwave, this is related to the Azores high pushing into S Europe.

As a result, the Atlantic high fails to push northwards. 

Before today, this had been the favoured outcome on the Atlantic ensembles. 
 

Today’s GEFS does have plenty of members in the op/UKMO/icon camp but equally it has plenty in the gem club. So the mean is only there to represent the bifurcating options

This winter, whenever we’ve had a ‘crux’ like this, the mild /flat option has usually won out. Even if it hasn’t e.g the start of Dec and Jan cold snaps, we haven’t managed a significant lowland snow event. Will this one be any different? 
 

 

 

 

[Model Output Discussion - Spring Has Sprung]

ECM also banging the euro trough drum

Fits the ensemble pattern pretty well. At the moment, it’s pretty clear where we’re broadly headed  up to around day 11/12 with good model agreement.  
 

After that, the cfs weeklies are hinting at a cool pattern for early March

 

I’m still too upset with the ec46 to post it. Whatever it shows, presume the opposite will happen!
 

[Model Output Discussion - Spring Has Sprung]

Gem with significant blocking by day 9 - not as cold as it might look at first glance but interesting nonetheless. 0z was blocky too.

Gfs has a go at a similar pattern, but ends winter in a way that would be, well, rather apt

Ensembles still keen on a euro trough / Ural ridge combo with systems feeding in.

 

Fairly good agreement between the GEFS and GEPS.

This cool and potentially stormy pattern might stop feb from being the warmest on record, but it won’t save winter for coldies. 

March on the other hand…

[Model Output Discussion - Spring Has Sprung]

18z has a cold northerly, an impressive euro trough and a possible build of heights over the top.

[Model Output Discussion - Spring Has Sprung]

The ensembles are  keen on a euro low. Here’s the big 3 for the start of March 

EPS

Geps

Gefs

The GEFS is the least pronounced, but the other two have a 1010mb low over the se med. 

Like the scandi high, this feature is modelled  many times more than it actually manifests. However, the models have to get something right at some point so maybe this one might verify?

Getting Atlantic amplification has also been hard to come by recently. To really take advantage of the euro low we need the jet to sharpen in the Atlantic. There are members that do this across the suites but not enough to have any confidence. 
 

If I was looking at these charts, post ssw, in a ‘normal’ year I might be getting a little interested. But, given the incredible backtracks on favourable patterns (for cold) we have had all winter, it’s hard to think of anything other than ‘meh’. We are getting to the point where we need more extreme variants on the ar pattern  to force a countrywide snow event. Indeed, I feel a flip to a flatter, zonal pattern is far more likely than more amplification when it comes to verification. My reasoning is based on an unfavourable ssw, the mjo headed to the cod / warm phases and the ongoing high solar background. 

Very happy to be wrong or for an argument to be posited to the contrary. I’m afraid my ‘faith’ has dwindled to the point that I just don’t believe the models anymore when it comes to cold or blocking.

Saying all that, it would be ironic if, after all the winter disappointment, that spring itself started with a cold spell. It wouldn’t be the first time…

[Model Output Discussion - Spring Has Sprung]

Might be time to get the towel ready.

The models have been appalling this winter. Seasonals, ec46, ensembles, Ops: all guilty. I’ll see if this euro trough comes off, about 40% of eps members support the gfs op. If not… I’ll hoy it in.

@Hotspur62 factors I can think of:

- high solar, in times of high solar I feel the models over estimate blocks and downgrade them as it gets closer, the inverse is true for low solar. Just my opinion, not wanting to start a debate. 

- Hunga Tonga impacting the strat

- the mjo has flattered to deceive - although in general I do feel it has led the pattern. 

- The Nino has been too strong and not east based enough and the lingering effects of the +iod were unhelpful

- the pathetic SSWs we have had have spoilt favourable trop patterns by revving  up the Atlantic, twice. (Ridiculous  to think about but somehow totally unsurprising)

- the eternal model bias towards over amplification in the extended 

The last one is the main reason I am losing the joy in what we do. It’s almost as if the modellers need to add an extra 2x to the Atlantic. It’s under modelled 80% of the time.

[Model Output Discussion - Spring Has Sprung]

What’s the ecm up to here?

It has high pressure clinging on well into midweek next week. All other output pushes a trough through at this time. 

@Mcconnor8 I see your point mate but I would rather the ec op than other output, it maintains dry weather for longer for the vast majority, seems to avoid a nasty storm midweek, and still looks like it might end up chilly and blocked by the end of the run - especially if the Atlantic trough disrupts enough…

192

[Model Output Discussion - Spring Has Sprung]

Generally it’s been quite a good morning for building the momentum that the 18z started last night and that the GEFS have been touting for quite a few days e.g a big scandi trough - AR combo in the 11-15 day range. 
The gfs op is very similar to last nights permutation 

Beautiful chart btw

The mean is very much on the same page and consistent over a few days now

Now the Nw heights aren’t currently progged to hold but, crucially, the euro trough is so we do have the opportunity to Build heights over the top towards scandi, especially if the strat  pv goes the other way ala gfs op.

Can’t think of the last time that happened mind so hardly a cert. Obviously any cold, blocked or even half pleasant scenario needs to be taken with a massive bowl full of sea salt after this winter’s modelling shenanigans.

The ecm, not that I trust a pixel that it pontificates these days, has conjured up a scandi high with a U.K. trough deconstructing against it. Make of that what you will.

The gem is settled for a good portion of its run than barrels in a U.K. trough. Notice the very -AO and Atlantic profile - certainly not standard fare and you could see a big northerly not long after 

 

The mjo heading to 4 is a poor portent to me. I find it is one of the strongest indicators of a strong Atlantic. The nature of the strat weakening feels odd to me too. A very brief reversal and a quick reconstruction didn’t help us in late Jan did it. On the contrary.

So there we have it. A rare 0z set that doesn’t completely vanquish cold prospects but instead teases and tantalises like it’s rowdy party time brother from the afternoon. Do we believe it? Probably not. Energy levels for the chase are seemingly at an all time low after let-down has become the norm this winter. 
 

This is the final chase for me. I’m already craving the arrival of mid/late spring (incidentally my favourite season in Cumbria - our dry season). If this quest fails unvaliantly - probably after the 6z haha - then I’ll be searching for south westerlies not sorrowing over them.
 

Are you in then, for one last ride, for old times sake?