Model output discussion - cold spell approaching?

[sheikhy]

What did i say about the 00z bringing us back down to earth!!!!we got problems these cold charts are struggling to get closer and when they do they are gettin watered down as always!!the only good thing bout this morning is the upgrade in snow for the midlands and for once the ecm is actually playing catch up on this event which is quiet refreshing to see!!!think we we need to look east between 72 and 120 hours just incase that ridge into scandi upgrades!!

[Frosty.]

There’s still plenty of cold GEFS 0z members for the last third of January!

️ 

[sheikhy]

14 minutes ago, Paul said:

3z ukv is quite snowy on Saturday, so suspect the fax may follow along similar lines.

Any charts mate!!!

[bluearmy]

A few days ago, the cold trough was supposed to set up across nw Europe initially from the ene. that is no longer the case. We should have established a cold upper trough into which the Atlantic would run (and that would be to our south). Now it’s more about that trough dropping down from the north in a less defined manner and the Atlantic running into that. You can imagine that this presents an issue where the two air masses phase much further north and west than the models had been showing. 

the envelope is still open though.......

[Vikos]

10 minutes ago, northwestsnow said:

Is it fair to say cold hunting in this country is a bit masochistic? 

Not only in your country. Seeing Spain drowning in snow while we have this wonderful green-brown enviroment is... the word with f and cked at the end plus an "up".

It's like beeing cursed, even the best options don't deliver anymore.

My last hope is a radical switch after the 20th as it was always pronounced to be the turn-over-point. I am confident that February will deliver some strong easterlys.

EC (12z) is still promising

  

Edited January 13, 2021 by Vikos

[KTtom]

17 minutes ago, Paul said:

3z ukv is quite snowy on Saturday, so suspect the fax may follow along similar lines.

Surely the UKMO cant be so wrong at just 72 hours...be amazed if this gives any snow on Saturday?

[bluearmy]

 

not liking this run (which follows on from the same theme).  Basically, the cold is lessening, run by run,  from the ens mean in the 7/10 day period ........

[ICE COLD]

Unbelievable. No beating around the bush from me . What a downgrade across the board . Not just 1 or 2 wobbles , the runs across the board are terrible compared to yesterday . Can’t believe how flat it’s gone in the mid range . Time to have a break , these  false dawns are frustrating the hell out of me man

[bluearmy]

1 minute ago, KTtom said:

Surely the UKMO cant be so wrong at just 72 hours...be amazed if this gives any snow on Saturday?

That’s Friday night and the surface ridge will be cold underneath 

[mulzy]

2 minutes ago, bluearmy said:

 

not liking this run (which follows on from the same theme).  Basically, the cold is lessening, run by run,  from the ens mean in the 7/10 day period ........

And the trend continues in the extended timeframe too (though not as mild as the GEFS).

[northwestsnow]

Mean looks a bit of a backward step too.

Hmmmm.

Bed time for me , hoping to wake up later to a swing back....

Edited January 13, 2021 by northwestsnow

[Tim Bland]

Thurs & Sat snow for the east from ECM ...

[Gustywind]

3 minutes ago, Broadmayne blizzard said:

Just another set of runs for something still a week away so these charts and people acting as though these are the ones that will definitely verify in every detail. It laughable really.

Trouble is once downgrades begin they usually go from strength to strength. In truth it began before this morning, with the much deeper cold from the NE being replaced yesterday with a more tepid/marginal affair, good still for the North, not so good further south. Now we’ve seen even this downgrade.

Those elusive Greenie highs remain elusive.

[Tim Bland]

Aperge further west & south with the snow tomorrow...

Euro 4 has snow as far west as central southern parts. Unlikely to settle much but could be a nIce surprise for for those who haven’t seen a snow yet..

 

Edited January 13, 2021 by Tim Bland

[Man With Beard]

ECM mean this morning, in keeping with most op runs, keeps the dividing line between cold and mild further up the country.

Still very good for cold further north, but southern areas would be biting finger nails. Heights to the south not falling enough here, which has been a danger consistently signalled. 

Not the final word on the matter, too close for that, just "more runs needed"

[DanDorsetUK]

For me this is a big precursor pattern shift. If PV-forecast last night was right saying a PV split possible today then everything we've been looking at was surely wrong anyway. This looks like an instant shift to goings on above. I wouldn't trust anything being seen right now. Almost looks like something you see with a Tsunami response with the tide rushing out before a sudden surge. 

[Paul]

25 minutes ago, KTtom said:

Surely the UKMO cant be so wrong at just 72 hours...be amazed if this gives any snow on Saturday?

This is what's showing.

Prec type:

  

Wet bulb freezing heights

  

850-1000 thicknesses

  

 

 

[IDO]

From an IMBY perspective, based here in the south, nothing has really changed. The models have been suggesting 2-3c below average as the trough drops with minimal snow chances and this morning's runs a slight downgrade in that, which is within expectations bearing in mind the proximity of the south to the base of the trough:

The above ecm means reflect this. The further north the better the chances for a couple of snow events from d5-10, but nothing memorable. Post-d10 is still a work in progress so no idea how that will go. We can go as far as saying that:

d6-10; Heights building to Greenland + cut-off low dropping over the UK. Then the Greenland wedge warming out. Minimal sustained cold flow so rather underwhelming cold pool. The gefs d10-16 have some interesting NH charts, but from a uk perspective not very good. Hopefully that will change! And we have Feb and March to get something better so unlike the late SSWE's we can afford to lose out on the initial stages of this event.

[Man With Beard]

I think it's possible to go too far the other way when looking at this morning's charts, though. The overall air mass has had an injection from a northerly direction at some point, if the ensemble mean is right. All it may take is a running channel low to put the UK on the right side of the snow line, the temperature profile is still just about favourable for that. So while yes, the charts could be better for cold and snow this morning, they are far from a write-off, either.

[Paul]

Another batch of posts moved to the chat thread - please only post in here if you're commenting on the specifics of the model output. If you just want a general moan about it, the chat thread is the place to do it.

 

[nick sussex]

The phasing issues have come back this morning .

The earlier phasing now makes it a struggle , delays any cold and the low blowing up over the UK is also not helping .

Ironically whilst all the attention has been on the medium term there’s still the chance of some more localized snow in the shorter term .

At this point I’d rather hope last nights UKMO had found a new trend and was ready to back everything west , rather than relying on scraps later on from the long winded Greenie ridge saga .

 

[Notty]

I posted a few days ago that the models were struggling after 14/15 Jan. The output has been very volatile recently and probably still is.

[Paul]

Following up on the 3z UKV, it actuallly has quite a lot of lying snow coming out of the front on Saturday, certainly something to keep an eye on...

  

 

 

[PiscesStar]

12 minutes ago, Notty said:

I posted a few days ago that the models were struggling after 14/15 Jan. The output has been very volatile recently and probably still is.

I woukd agree the period to watch is 19th January pivotal around that date as developments go

[DEYS(Kent)]

Whilst the deep cold runs and the specific synoptics have undoubtedly changed, I really do advise to hold off the wrist slashing for 48hrs. That said, if the latest trend continues; the blocking in the Atlantic should still be sufficient to send LP’s on a more southerly track which sets up those battlegrounds. All is not lost and still hopeful of the second bite of cold from the NE to arrive..

Edited January 13, 2021 by DEYS(Kent)