Model Output Discussion - Spring Has Sprung

[northwestsnow]

Suprise suprise..

Here come the Stella winter charts, in spring.

 

[KTtom]

 northwestsnow yea, sadly not unusual as the PV weakens in spring. Even with that chart the air source over the UK is circulating round the low and now a direct easterly. A look at the ens, a few still living the dream, including the op, but the vast majority following the average line and creeping into possitive values. As Met4cast said yesterday, unlikely to see anything particular cold or warm over the next 2 weeks.

[Lukesluckybunch]

Ecm watered down this morning...gem isn't having any of it,and the ukmo not quite so good!it's going to be one he'll of a struggle to get a decent nationwide cold spell..from now on!..this chart somes up the uk weather..quite often close but rarely the full show!..I think the most likely option is a few colder days 5/6c..but a cold and snowy spell..I would give only 10/20% chance

Edited March 3 by Lukesluckybunch
Adding

[IDO]

 KTtom

The trend, if anything, for the south is less cold 850s and milder 2m temps. In fact, after this brief colder few days the 2m max mean in London stays above 10c until D16 with some members going close to 15c. If we want to pluck a few cold runs out, we should also look at the milder ones. Hence why we use the mean:

There is a clear rise in temps over the next 16 days. We need to see the trend of moving in the opposite direction to be hopeful of a cold finish to winter. 

Gem to D10 and even less keen on any significant UK cold:

We remain on the cold side of the jet but the NH pattern needs a little nudge as any harsh cold is falling to our east and west^^^.

EC to D9:

I do not post D10 EC charts for obvious reasons!

So it looks like decreasing chances for the UK to see any of the cold spilling from the Arctic without a reset from tropical forcing or the models to change the current predicted pattern.

[Lukesluckybunch]

A few have mentioned it..but apart from a few cold op runs..the ens across the major models..have never really fancied something cold!

Edited March 3 by Lukesluckybunch
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[Chesil View]

As usual for the past few months the road to getting any genuine deep cold to the UK is proving a long and tortuous one.

[Mike Poole]

9 hours ago, Rain All Night said:

Note the new (to Meteociel) addition here - the ECMWF machine learning model, AIFS.

Good spot!  It will be much easier to bring this into the discussion more if it is in the same format and with the same plotting variables as all the others!

Edited March 3 by Mike Poole

[Jordan S]

I somewhat agree with @Met4Cast in terms of a flattening out pattern around mid month, and it would to some extent tie in with my thoughts of higher pressure moving south over UK around same time that I’ve mentioned previously which would ofcourse be a precursor to the Atlantic lows return along with milder air and subsequent unsettled weather attempting to cover all areas with some form of “flattening” of the pattern over our part of the Globe, with declining blocking from high latitudes around mid month, though perhaps slightly different thinking with me thereafter in that some form of high pressure may retreat to Greenland also and that would still result in the synoptic likelihood I have mentioned previously with two potential opposite transitions, a colder pattern trying to develop from our northeast but an equally very mild pattern trying to establish further south, note with heat beginning to really build over Northern Africa by this point.. , low pressures are aiming right for southern UK by this point pretty sure of that past mid month, sadly that means further potential rainfall issues, possibly making March somewhat wetter than normal for the south even with the drier few day’s expected around mid month, but not as much as February, northern areas may see a drier than average March with a more wintry period for a time past mid month before a milder and wetter regime returns here too by months end and declining Greenland heights .we’ll see

Showing these anomaly charts below because they highlight the north/south split very well, especially synoptically. The unsettled conditions returning to the south only for a short time from 8th anyway, before the drier conditions return for a time here. We’ll have to see if these charts below show a similar or same synoptic pattern as I’ve described for mid month onwards above when the time in question is properly within the charts time scale. But I would say it’s a reasonable bet they will.

 

@Mike Poole the Ecmwf ai model has also been introduced on the charts I use, couple of them I posted yesterday, was a pleasant surprise to see those appear and with the same variables as all the others to look at.

Edited March 3 by Jordan S

[Anthony Burden]

Morning all,ECM/GFS /UKMO/ICON all showing some very cold air in Europe in fantasy island all about the positioning and orientation of the Scandinavian high if it starts to filter over the UK.Nothing clear cut as yet,interesting to say the least one thing certain no spring like weather on show as far as I’m concerned.

[Penicuikblizzard]

 Anthony Burden no

winter weather on show either looks like more of the same cold rain as has been throughout the whole of this winter 

[Lukesluckybunch]

BBC going for a blocked month...focus of the hp to be over Greenland area

[CoventryWeather]

I'm personally not buying the colder runs at the moment, until we start seeing some sort of consistency from the Operationals and some movement from the ensembles, then average seems the way to go.

Continuation of a wetter theme, although perhaps not as much as recently. Anything cold seems limited to the north east, the south most likely keeping somewhat milder with a southeasterly. A fairly N-S split but nothing really unusual for early spring.

On regards for the stratosphere reversal, most likely to come into play past mid month. I'd say this is possibly when colder synoptics will be more likely, especially in a northerly more than an easterly.

[syed2878]

 Lukesluckybunch   looking at some of the models this morning, I think your being rather generous with the prediction of 1020% chance of a nation wide called snowy spell I would go as far as giving it five or 6% chance thank goodness this crap of a winter is over so much potential such a failure that’s the story of winter, 20,23, 20,24 for the southern half of the country anyway

[Scandinavian High.]

Interesting charts starting crop up now milder wetter to start to march . later part week 2 of march  Im  looking around 16th onwards turning much colder from east with wintery weather I’m thinking models are being to early bring in the colder weather from east. My forecast don’t shoot me down please

Edited March 3 by Scandinavian High.

[January Snowstorm]

The 06z isn’t any better. 

Edited March 3 by January Snowstorm

[Lukesluckybunch]

37 minutes ago, syed2878 said:

looking at some of the models this morning, I think your being rather generous with the prediction of 1020% chance of a nation wide called snowy spell I would go as far as giving it five or 6% chance thank goodness this crap of a winter is over so much potential such a failure that’s the story of winter, 20,23, 20,24 for the southern half of the country anyway

Well that percentage being the absolute max..I'm talking a nationwide cold spell 4/5 days with temps 2-4c!..yes I agree the models have been all over the place..we have learnt not too trust even the best models at 4/5 day range!!

23 minutes ago, January Snowstorm said:

The 06z isn’t any better. 

It's the same old story..getting pushed back further and further!I will give it too day 7/8 see what happens..it's looking like this run wants to push all the cold north!dire..it's an absolute horror show by 228! 14/15c in South!

Edited March 3 by Lukesluckybunch
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[Penrith Snow]

 Chesil View At this rate any cold leaving the Russian Arctic next week  will arrive just in time for Christmas!

[Met4Cast]

On 26/02/2024 at 10:48, Met4Cast said:

With the recent sharp fall and rise in AAM tendency it does seem plausible that we'll see the jet stream encountering some road blocks in the form of high pressure, probably to the NE of the UK (though as mentioned previously, the high probably too far NE to influence the UK much) before the pattern flattens out again by the end of week 1 into week 2 of March.

 

Going back to this post from the 26th February we are now seeing this broader evolution play out within modelling. 

High pressure forming across Scandinavia but increasing support that it’ll be too far NE to really drive energy SEwards & advect cold west across Europe. 

The pattern flattening out is now well advertised. 

I think it’s probably fairly safe to rule out any cold weather through the first half of March & probably beyond now. 

Edited March 3 by Met4Cast

[Cambrian]

The most populated of the 3 clusters from the 0z ECM ensemble at day 10, which gathers 28 of the 51 members, is a NAO- scenario. The representative member is 14, showing the UK and Ireland in a flow off the continent, chilly at the surface no doubt, but not cold air at T850. From there, the low to the southwest runs along the southern flank of the high pressure before fizzling out. The high then relaxes south before the next Atlantic low brings us into a flow from the southwest by day 15. 

   

Cluster 2 has 13 members and is a more blocked scenario at day 10. The representative member is 47, which has the UK in a dry, cold, easterly flow from Russia. Again, the high sinks south by day 15, low surface temperatures probably but the cold air is pushed to the south over Italy. Nice March weather that one. 

  

Cluster 3 has 10 members and though designated as a blocking scenario, it doesn’t look very blocked from the perspective of the UK and Ireland (nor for the rest of Europe for that matter), the representative member is 49, with an Atlantic westerly flow presiding. By day 15, the pattern is cyclonic with some hints of a chillier polar maritime influence eventually on the way from the northwest. 

  

So, all in all, presently looking like a strong signal for an easterly flow but only roughly 1 in 4 chance of a cold easterly for a short while around day 10, before the Scandinavian high sinks south, perhaps giving us a few days of a pleasant anticyclonic influence, but more likely the Atlantic pattern reasserting itself by day 15. 

The ensemble mean captures it nicely, with a southeasterly to easterly flow at day 10, rather cold for a few days, before the next Atlantic trough approaches bringing us into a flow from the west by day 15, with temperatures recovering to near normal. 

   

By then, we’ll be two days away from the spring equinox, and just a few days from the Easter break. ‘Nuff said.

Have a lovely Sunday.

[Rain All Night]

13 hours ago, Rain All Night said:

12z deterministic runs, out to Sat 9th (day 7)

Note the new (to Meteociel) addition here - the ECMWF machine learning model, AIFS.

12z ensemble means, out to Sun 17th (day 15)

It's been 36 hours since I posted the outputs, and what I see now is that we're left with the impression from the ensemble means that the high-latitude block will collapse from about 13th March - I think @Met4Cast has been predicting that. However, the subsequent signal is for a mid-latitude block, so all is not lost in the dryness stakes.

0z/6z deterministic runs, out to Sun 10th (day 7)

Oh pleeease let that low go under and not blow up, I so want to stay dry...

0z/6z ensemble means, out to Mon 18th (day 15)

These ensemble means suggest that the low won't go under, and that the pattern will flatten out from 13th March (or earlier on the GEFS), with less sign of residual mid-latitude blocking than yesterday. Rats.

[Derecho]

Just to add some further interest to this thread. The new EC weather model which incorporates AI machine learning is now available on WZ. Will be interesting to see how it performs!:
 

Wetterzentrale - Top Karten - AIFS Europe 06Z

WWW.WETTERZENTRALE.DE

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Wetterkarten AIFS Europe 06Z

 

It's on the colder side of things for its latest run.

[Rain All Night]

 Derecho I've just noticed from the blurb on both Meteociel and Wetterzentrale that the AIFS runs out to 360 hours on all of 0z, 6z, 12z, 18z. So now the GFS won't be the only "pub run" available for us to view on these sites!

Edited March 3 by Rain All Night

[Rain All Night]

26 minutes ago, Derecho said:

Will be interesting to see how it performs!

The evidence so far available... ("IFS" is regular ECM)

AIFS day 10 is about as good as classic ECM day 9

https://charts.ecmwf.int/products/plwww_3m_fc_aimodels_wp_mean?area=Europe&parameter=Geopotential 500hPa&score=Anomaly correlation

Edited March 3 by Rain All Night

[bluearmy]

 Rain All Night the ec control should also be used as an op to day 15 but by the time it’s out on meteociel, most are warming up for the 18z gfs 

pedeantically speaking only the 18z gfs is the pub run

[Rain All Night]

 bluearmy I'm hoping the AIFS runs don't take quite as long to be published as the ECM ensemble/control runs.