Model Output Discussion - Spring Has Sprung

[jules216]

Following on the previous post dare I look at T850hPa outcome and its quite shocking about +7°C anomally before *if that trough clears. Taking it to extreme about that time of year for settled Snow I need here about -9 uppers and they are going wrong way to start with. How on earth would that trough suddenly pickup about 14°C colder uppers if it manages to be a cut off feature oscilating somewhere west/central Europe. This is more then enough evidence to throw in the towel if one doesnt wear a huge "rose glasses" and doesnt accept reality/most likely outcome. There very little alternative available to be even 10% optimistic.

[BarnetBlizzard]

For us in the UK the GFS 6z mean is a bit of an improvement in comparison to the 0z mean. More energy sliding SE across UK into Europe - the more the better. 

You can bet if we were still in the 70s and 80s then you'd get more energy disrupted south east as we got closer to T0 - unfortunately it's 2024 and what can go wrong normally does. 

If i were to look at my glass half full, I'd say we're in with a chance of something exciting in the next 10-12 days. 

[AO-]

Note the (huge) difference at day 9 between GFS and EC. I believe GFS has a bias in throughing, so it might as well be a less progressive outcome. If the shortwave holds back even more than in the EC scenario (of which I'm not sure is possible), then it could be game on. Sliders could emerge it the shortwave becomes a slider eventually due to higher pressure from the north. As did, it is a very delicate situation in which everything can go wrong. With some luck, and this will become clear in a few days, it might end up in the right direction. But given the history of this winter the probability of the cold not getting far enough South is very likely.

Edited January 31 by AO-

[AO-]

P03 is also a possibility and it's a scenario that is preferred by me, but certainly not unlikely. Shortwave moving through and advecting cold air south.

[E17boy]

Hi peeps,

Right I am going to give it just one more week to see where we are by next Friday Feb 9th. If by then we have not seen any positive swings in the output then I think it will be time done for me for this season. There’s me hoping there will be a turnaround but as things stand it looks like a fighting battle to see some good output  for the reliable. Although deep down even the alarm bells are sounding but we live in that hope.

[ANYWEATHER]

 BarnetBlizzard believe me it did go wrong lots of times in the 70s and 80s

[BarnetBlizzard]

6 minutes ago, ANYWEATHER said:

believe me it did go wrong lots of times in the 70s and 80s

True... but it did go very right in a similar set up on one occasion 

 

Edited January 31 by BarnetBlizzard

[Battleground Snow]

It was disappointing to see the models step back from a block/wedge to the north this morning,

Perhaps the erratic nature and slow progression of the mjo wave is to blame for the uncertainty.

The plots still look good but, its taking a long time get into phase 8.

Any further delays will not be welcome with the season drawing to a close.

 

 

Edited January 31 by Battleground Snow

[Rain All Night]

15 hours ago, RainAllNight said:

12z ensemble means, Wed 31st to Tue 13th (day 14)

GFS is still determined to scrape us with the northerly on 5th/6th Feb.

At face value, the ensemble means are showing us a cyclonic period of weather from the 8th to 12th, as the high pressure to our south yields. But check out the northern flank of the mean low pressure area on the ECM ensemble... rather flat, isn't it? Now granted, the mean easterly is aimed at Iceland, but the deterministic run (further down this post) shows us that it's possible that it could end up further south.

At the end of week 2, pressure seems to be rising again from the south.

12z deterministic runs, Tue 6th (day 7)

The T+168h charts are messy around the UK, which I think is rather interesting to note in the circumstances.

12z deterministic runs, Fri 9th (day 10)

I wouldn't normally show individual runs at day 10, but let's give ourselves an excuse to view those ECM and GFS wedges once more, alongside some less savoury suggestions of what we might see instead should those wedges fail to form.

0z/6z ensemble means, 31st Jan to 15th Feb (day 15)

No change to the expectation of a switch to a cyclonic spell of weather from 8th/9th Feb, and it still appears that after about five days of this, pressure will start to rise again from the southwest. ECM's mean low pressure area is noticeably less intense than that shown by the GEFS (and still has a flatter top), implying that the ECM ensemble members might offer less miserable weather for the UK than the GEFS ensemble members.

0z/6z deterministic runs, 7th Feb (day 7)

The end of the semi-reliable timeframe is still a day or two before the expected pattern change, so the appearance of any "saviour wedges" would still lie just beyond this - unless you ask the ICON.

Edited January 31 by RainAllNight

[Tim Bland]

Only decent op chart I can see now is the GEM which looks similar to last nights ECM, let’s hope models revert back to this ! 

[AO-]

A lot of variation in the GFS output at day 10, but the majority of the members is going along with the operational. The more interesting members show a lot of scatter and there is certainly no clear direction among them. But I think day 8-10 is the key timeframe for a change, if any. 

[Derecho]

With the phase 7 transition coming right at the start of the month, I was unsure what kind of synoptics we'd get. Clearly we are leaning towards this composite for a brief time rather then the much more favourable January composite. Then a loop into phase 6 if the EC is to be believed (the GFS lingers in phase 7). The output does bear some similarities to what we see below:

More so with the phase 6 composite on the right but note the phase 7 composite has the Iberian positive GPH anomaly along with to the NW. Again we will struggle to get notable cold until that goes.

Phase 6 doesn't favour an Iberian high anomaly though that may be brief if the below plot is anything to go by. Any progression into phase 8 of the MJO looks highly uncertain and painfully slow if it does. A shame because that composite is highly favourable towards cold.

Though we seem to be hitting a brick wall in phase 7. The EC does make it towards the end of February but we probably wouldn't see a response until early March. Sadly I'm running out of patience with this winter. It hasn't been a good one.

February may still throw up a surprise but I'm highly doubtful now. The soil temperatures from the mild spell and the increasing solar radiation as we go through this month means it'll be tricky for snow to stick even in great synoptics unless we get exceptional cold.

I'd rather have some nice weather and save on heating bills unless we get a beast from the east. Come on models, show us some improvement in the next few days otherwise I'll be going into summer mode.

 

 

[Daniel*]

Generally the overnight guidance was an improvement. 

GEM latest and previous 

 

UKMO 

 

ICON 

[SLEETY]

Ecm  00z ensembles were  trending colder breaching the minus 10 hpa mark previous runs hadn't breached it.

Edited January 31 by SLEETY

[Daniel*]

There seems to be more enthusiasm for progression into phase 8 mid month - timing wise this feels like 2018.

[BarnetBlizzard]

Not a bad start on the ICON - energy disrupting south-east. Can we keep a wedge of higher pressure in the area circled? 

 

[northwestsnow]

ICON will do nicely

[danm]

 

[danm]

Multi-model confidence is much lower than usual post 5th Feb. Basically they don't have a scooby what will happen:

[Rain All Night]

14 minutes ago, BarnetBlizzard said:

Not a bad start on the ICON - energy disrupting south-east. Can we keep a wedge of higher pressure in the area circled?

 BarnetBlizzard Just to nitpick, it's actually going due east, the hemispheric view makes it look like it's southeast:

Edited January 31 by RainAllNight

[DavidS]

12z ICON is not quite as good as the 00z but at least some consistency.

[feb1991blizzard]

GFS is going for a quick kill in a few frames.

[Lukesluckybunch]

It looks to be that even with a fairly weak vortex,we still can't get lucky!

[Battleground Snow]

 Lukesluckybunch

Gem should head where we want it to around 192. Decent wedge in and around Greenland 

Ukmo looks okay at 144, 168 will be more telling when it comes out though.

Edited January 31 by Battleground Snow

[Metwatch]

Can only hope this gets a southward trend... Unless you're in the north.

Good signal for Greenland pressure rise now and lowering in Northern Spain:

Edited January 31 by Metwatch