Model Output Discussion - Spring Has Sprung

[Anthony Burden]

 Met4Cast Hi a usually safe statement to make with global warming,but I feel spring will be held up for sometime I don’t think we have to wait to long to find out the effects of this major SSW.

[Sherry]

 Anthony Burden highly unlikely anything will happen 

[phil nw.]

Starting to think that this next strat warming could end up with it being the final one.

The slow rate of downwelling of the negative zonal winds look like taking us well into March.

With the return of the sun across the pole it seems unlikely that much if any recovery of the strat.vortex will occur by then.

[KTtom]

My personal feelings was that this SSW was far too late to help the UK into a wintry spell, but boy, I do hope it knocks us out of the diabolical pattern we seem to be stuck in..GFS for next weekend dominated by yet another UK limpet low with knowhere to go!

Edited February 25 by KTtom

[Bricriu]

I think the second half of March will be quite cold due to the SSW- but probably too late in the day to bring wintry nirvana.  The lament of if only this was a month ago might be expressed.

[geordiekev]

4 hours ago, Met4Cast said:

In essence though - For those still chasing cold/snowier outcomes, I think it might almost be time to give up the ghost. 

With the unreliability of most of the models/teleconnections beyond 10 days, it's a brave person to make forecasts out to the far envelope of possibilities which is different obviously depending on location & altitude.

For me, as Cambrian states it's the lack of an organised trop PV which I feel has blighted the usual IMBY opportunities, as 10 falling days is below average thus far up here.

The 'normal' zonal pattern does nearly always present gaps in the Griceland area for a good old omega block but this seasons disjointed & disorganised tPV patterns, due to the early Canadian warming, won't be on my Christmas list next year for sure.

My birthday after mid month does more often than not end up snowy, so for me I'll hold out till 21st with the towel

[Metwatch]

5 hours ago, Mike Poole said:

Looking at the representative members at T144, the 580 hPa temperatures are as follows (in order for clusters 1-5):

If those really were the 580hPa temperatures, I would be quite worried!

[Cloud 10]

12z GEM looking quite blocky,with a succession of troughs dropping down from the North backing further West each time.

 

[minus10]

Another trough dropped down and nowhere to go on the gfs 12z...

[phil nw.]

Models continue to show a slow moving pattern with further lows dropping in from the north west keeping us rather cold and unsettled.

The next attack from the nw showing for Thursday/Friday brings some lower uppers with the rain but any snowfall seems limited  to higher levels now,

 

The UK trough continues to be modeled as an ongoing feature,trapped between heights to the east and west.

 minus10

Yes It seems we are stuck in a rut with this pattern.

[RJBingham]

It's all a bit meh. 

[MJB]

23 hours ago, Mike Poole said:

For me, unfortunately, the evidence seems to increasingly suggest that we can no longer get the right set up, during the months that matter, or at least it is now extremely unlikely

I doubt that very much Mike .

We will get cold in the months we know to be Winter without a doubt. 

One big thing that has come out from this season is , many people on here are very very knowledgeable and know more than I ever want to know if I'm honest. 

It's clear we and the super computers and the professionals still don't know enough. Back loaded winter was mentioned, seasonal models claimed a colder end to the winter SSW's yet in this part of the world not a snow flake.   

We can forecast 7 days out reasonably well , 10 days in a mobile pattern, specifics aren't always accurate and that's your lot. The caveat would be when there is a stubborn HP...........dry and sunny , dry and foggy with frost.

Just my opinion of course and we all have those whether its mild or cold  

[Cheshire Freeze]

Any dry spell looks on thin ice to me- two week rainfall totals approaching 80-90mm in places

We look to be well and truly in the midst of an extended wet period.

We could well end up with a slow moving undercutting jet through March (given any modelled HP will likely end up further N due to SSW effects).

Edited February 25 by Cheshire Freeze

[Metwatch]

Already 6 years now since the Beast was about to be unleashed to our shores. How many more years until a SSW will deliver something similar again I wonder, maybe 10 or 20...

[WYorksWeather]

Still pretty much a holding pattern for now with the GFS. The ensemble shows a bit of a warming trend into early March as to be expected at this time of year. But it's all relatively close to the 30-year average, so neither unduly cold nor warm and spring-like, though usually these sort of patterns end up a little above average. Pressure does look like rising as well so hope of something drier, but not exactly very enthusiastic, with the mean only briefly topping 1020mb in the south.

Probably the best thing I can do for a bit of light relief in this instance is to take a look at some of the more entertaining outliers. So for a bit of laugh, let's look at P27 of the GFS. How on earth do we get a -5C 2m temperature (and a -15C 850hPa temperature!) in the middle of March?

It all actually starts with a very mild spell. Around day 10, we get the Azores high ridging in, and in fact some very mild temperatures.

Much the same around day 12.

Again much the same around day 13, but something is stirring around Greenland - a massive block setting up!

Day 14, and the cold air begins to move - a textbook northerly.

 

And then this is just to marvel at. 12 hour steps from T+348 to T+384, with the 850hPa temperatures. An enormous chunk of the Greenland cold pool gets dragged southwards, and we even have the -16C isotherm over the UK briefly. Absolutely unbelievable for mid-March!

Of course, this entire post is just for a bit of fun, we all know this chart is bonkers and will never verify. But what a crazy chart it is!

Maybe the ECM later will have something equally crazy in its ensemble in the opposite direction...

 

 

 

 

[Summer8906]

 Cheshire Freeze Hope not, that might produce something (incredibly) wetter than 2023 if that were at all possible. Just hope that the current modelling for March is as wrong as models for February were around the turn of the month.

[Norrance]

 Metwatch Just took three years for here at least. 15 inches of snow by the 10th Feb in 2021.

Edited February 25 by Norrance

[Mike Poole]

ECM clusters tonight have some interesting setups, T192-T240:

Strong (red border) signal for blocking around Scandi there, clusters 1,5 and 6 the potential to bring winds from the east, but probably south of east on clusters 1 and 5 so its unlikely to be particularly cold.  Clusters 2,3,4 have UK in a southwesterly.

T264+:

A variety of patterns there, but some high latitude blocking in most, with clusters 3 and 4 showing the coldest evolutions.  Cluster 6 on its own with high pressure into the UK in week 2.

Zonal winds chart showing a strong reversal consistently now, could strengthen an existing signal for blocked patterns into mid-March, interestingly the mean does make it back into positive territory into April:

 

[Jordan S]

 Cheshire Freeze

I agree, except for the drier* and milder couple of days that are likely after 3rd further south/southeast curtesy of transitory heights moving across areas south of the uk on the dates shown on the charts below.. 

It’s looking generally very unsettled for many, especially southern UK through first half of March as a whole especially later in the second week of March, Scotland may fare better by around the 10th onwards with blocking highs set to feature to our north as my post yesterday and indeed as your post would also indicate.

Gfs 12z certainly the more extreme wetter scenario it has to be said, but I think the pattern it shows is quite accurate going forward, stalling cut off lows in abundance to our southwest.

[WYorksWeather]

ECM at T+240 eventually gets us some higher pressure, though a lot of rain to get through first. 

The ensemble still struggling to decide what to make of it as we go further into March. High pressure is definitely an option, but I still feel quite uneasy until we see that mean pressure line consistently well above 1020mb for a prolonged period. Temperatures most likely a little above average for the time of year into early March, but plenty of scatter still evident.

It does seem to be a long process this, waiting for some clarity on where we go after the likely cold (but not very cold) plunge next weekend. Until proven otherwise, probably can't go wrong with saying likely drier than of late but not totally dry, and warmer than of late but only slightly above the early March average.

[ANYWEATHER]

At least day ten from both ecm and gfs show something drier from  the east .....☺

[Dennis]

pattern seems to change into march

 

[stodge]

Evening all

Some very interesting output this evening from the 12Z suite.

Having been the first to moot the idea of next weekend's LP disrupting to the south, both GFS and ECM have moved on having the likes of GEM and JMA looking they are 24 hours off the pace.

Neither GFS nor ECM have a "clean" disruption of energy to the south allowing the ridge to build through the mid Atlantic and into Scandinavia. Instead some energy heads back west to the Atlantic and restarts the mobile pattern. GFS has a third attempt at dropping the trough through the British Isles in the second week of March and for those hoping for some respite from rain down in the south, this is the nightmare scenario as the cut off LP takes up residence close to southern Britain keeping unsettled conditions going for a while.

Presumably due to the weakness of the PV and the decrease in zonal winds we see the jet weaken and amplify into March with the trough stalling or dipping south with heights extending towards Greenland - again, nothing unusual in and of itself though perhaps a month or so then we often see so it ends up an April synoptic pattern.

KSA 12Z has a pretty good take on it though I've seen no verification stats for the South Korean model.

[andymusic]

what have we got here then - pub run gfs 18z lovely scandi and reversal around 8th/9th March and then the cold 850s ploughing in too - we shall have to see - but it could be the ssw effect incoming!

North Sea Snow machine kicking off too

into la la land around 10th/11th March alot of the UK have snow

Edited February 25 by andymusic

[Battleground Snow]

 andymusic

Poor winter overall, but still wouldn't turn my nose up at this.