Model Output Discussion - Spring Has Sprung

[bluearmy]

49 minutes ago, CoventryWeather said:

There's a risk of something cooler later next week, looks like a core of the polar vortex moves near to Scotland. 

Most wish that were so 

sadly it’s just a deep low spawned from the remnants of the Newfoundland segment 

the Atlantic is way too warm for anything to survive the long sea track from n America. Certainly opportunities for snow over the north of the U.K. with elevation 

we’ve seen a couple of gfs ops headed more blocky - is that a consequence of the reversal high up now being in the starting data ?  if it continues then you’d have to wonder …

[phil nw.]

 bluearmy

It's been a strange season wrt trusting any strat.forecasts and the nwp projections from them.

Zonal wind forecasts have been widely variable.We have had instances when we have dipped below 0m/s but they been very brief.

We have been running with a weaker than normal vortex for much of Winter but never really benefited.

I can only conclude that the warmings have not been sufficient to impinge on the trop.pattern.No real split in the spv but plenty of displacements which just haven't worked for us.

Back to now it would be sods law that March could well deliver Arctic blocking as the vortex naturally begins to warm anyway.

It wouldn't be too much of a surprise to many of us to see the best cold charts since early December appear before next month is out.

 

[bluearmy]

 phil nw. I think the lack of strong reversal below 65N has meant we’ve not seen an appetite to drive blocking at a latitude that delivers deep cold uppers to where we would need it to 

we’ve had a lot of neg AO this winter (likely a consequence of the warmings early dec and first half Jan) but this hasn’t forced the cold far enough south. If we’d seen those reverse flows properly getting down to 60N then maybe we’d have seen the February many expected

 

[Purga]

Looks like an early Spring for March or rather a merging of a dismal continuous autumn into spring. Winter was virtually absent,

[Uncertainty]

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…

[damianslaw]

Where are we heading as we enter latter stage to February..

GFS, ECM and UKMO all in strong agreement of a generally very unsettled outlook, but we lose the very mild south westerly flow in exchange for a westerly becoming north westerly flow. Tropical maritime air then returning polar maritime, and eventually polar maritime air. 

Alot of dull wet weather ahead.

Northern high ground likely to see some snow, temps trending back to near average.

 

 

[Stuie]

 damianslaw You have summed it up well Damian.

[Mike Poole]

Clusters T192-T240 have pretty high confidence in a northerly by day 10:

Just cluster 4 not going with it.  However, on none of the clusters is it a long fetch northerly, trace the contours north, they soon veer to the west, so the ultimate source is not going to be very cold, earlier in winter the same might have delivered better, I guess.

[joggs]

Absolutely horrible outlook from most suites(I'm looking for warmer and drier now).

Absolutely suck to death of soggy ground.

I'll bob back in a week or so and hopefully see something more settled in the horizon.

[Uncertainty]

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!
 

[feb1991blizzard]

3 SSW's in one season and hardly any snow anyone??

[Frigid]

 feb1991blizzard Mean going below 0 again in March.. laughable really. The strat has been trolling us all winter, only about time it delivers the goods 

[bluearmy]

Just noticed that some of the AI models now go to day 15 

be interesting to see how their verification stats check out 

[Met4Cast]

8 minutes ago, Frigid said:

Mean going below 0 again in March.. laughable really. The strat has been trolling us all winter, only about time it delivers the goods

In fairness that’s not too unusual, will likely be the final warming. 

[stodge]

 damianslaw Indeed, the Iberian HP retreats west into mid-Atlantic allowing the trough to drop down through the British Isles ushering in a cooler and more unsettled phase with plenty of rain and wind and for higher ground as the PM air digs in, snow.

That's basically a week on from now but beyond that, plenty of evolutions and no real clue. 

The negative alignment prompts a strong pressure rise in mid Atlantic but will that translate into anything favourable for UK cold? Another option is the souward jet will encourage more LP from the Atlantic to move in from the west and of course we could see HP try to move back into Europe to reset the mild pattern. 

All up for grabs at the moment.

[bluearmy]

 feb1991blizzard  first week march is v early for a final warming so could be 4 tech reversals !

[feb1991blizzard]

 bluearmy

yes, i am thinking this (mid march) will deliver the blocking but too late!, just an (irrelevant) sidenote though, not all EC46 members show this upcoming one to be a reversal, not sure about EPS & GEFS.

[Blessed Weather]

 bluearmy

Apologies for being pedantic, but strictly speaking any SSW in March (assuming it's not the final warming) would be technical reversal number three. The SSW on the 4th Jan was a minor warming, i.e. no technical reversal of zonal winds at 10 hPa 60N. There was a full technical reversal on the 17th Jan and we're on course for the second technical reversal in a couple of days time. More info in the latest NOAA blog co written by Laura Ciasto and Dr Amy Butler:

A polar vortex double header
The majority of the forecast models say yes, the polar vortex winds will briefly reverse direction within the next week or so, commencing the second major sudden stratospheric warming in as many months.
https://www.climate.gov/news-features/blogs/polar-vortex/polar-vortex-double-header

[bluearmy]

 Blessed Weather you’re not being pedantic BW 

I just followed what had been posted earlier without counting !

[Chesil View]

Time for me to call it a day for this winter from a southern snow lovers point of view.  Its been a frustrating one promising much but delivering very little of substance.

Even the northerly progged around day 10 just means cold wet instead of warm and wet.

The weather will probably continue to take the pee and bring a blizzard in April but I can't be bothered to sit through another 6-8 weeks of daily runs to see great looking synoptics with uppers that won't cut the mustard.

Edited February 16 by Chesil View

[ANYWEATHER]

Probably ,turning colder by day ten then....ecm and gfs start to remove high pressure from southern Europe. Watch out ,for some brutal weather across southern Europe by late March into April. Flooding and snow  will be making the news and that's just the start....!  The UK,  on the periphery of drier , colder weather ,but lots of sunshine. As the PV weakens given the time of year ,winds turn more northerly and perhaps easterly .......

[WYorksWeather]

Right, quick evening post.

12z ensembles

Mostly a mild pattern up until the 23rd, then colder than average at 850hPa level, but still near average at the surface. ECM and GFS ensembles are broadly telling the same story. Possibly a little cooler than average at the surface further north.

Meteogram

The ECM meteogram for Reading has actually got slightly milder. Looks like only a couple of days of north-westerlies, then more of a split with a higher chance of a return to south-westerlies by the final couple of days of February and into the very early stages of March. Mild nights and near average days.

SSTs

In absolute terms, SSTs are likely to stop falling by the end of the month.

Days 0, 5, 10 and 15 below. 

In anomaly terms, we continue to see the warm Azores SSTs persisting. Definitely a major part of our current turbo-charged mild weather. Days 0, 5, 10 and 15 again. Maybe a slight moderation by day 15, but that's all.

Summary

Something a little closer to normal towards the end of the month, but only a drop in temperatures to around average.

It is too early to have much of a view on where things will be in early March but certainly not a strong signal for cold at this stage.

[Dennis]

Good weekend to all

NOAA

[Dennis]

 late febr/start march

patternchange 

[Gadje]

 Chesil View Thanks for your input. Your positive and informative posts I've enjoyed reading like many here. Till the next chase . Perhaps its time for spring.

Edited February 17 by Polar Maritime
To move discussion on.