Model Output Discussion - A cold start to Spring?

[seabreeze86]

GEM keeping a small pocket of higher pressure in the Atlantic. This is what Nick S was hinting at the other day I think 

[EML Network]

11 minutes ago, Cambrian said:

12z GFS op at day 5….

 

Hammer blow.

 

Can someone explain why in that bottom chart theres a big area across Southern Scotland that shows as rain ?

 

[Cloud 10]

GEM snowfest by day 8.

 

[Tog]

36 minutes ago, lawrenk said:

To those more knowledgeable than I, is this situation comparable to March 13, when we spent what felt like a week worrying where the rain/snow divide would be, only for the incoming low to be corrected so far south that it was Jersey and Guernsey that ended up getting buried?

Not knowledgeable, but I think it was March 13 we had masses in Jersey but none in Mar 2018.  I can say just a few miles between Jersey, Guernsey and Alderney makes a huge difference with sometimes one island getting nothing and the others buried. 

[Ali1977]

Still cold with the UKMO at day 7, but not a great looking set up unless the heights regain some strength 

[That ECM]

I was hoping for better tbh

[Spah1]

Looks like a 2 day cold snap. UKMO 168hrs loses the blocking. 

[nick sussex]

Oh dear what happened to the UKMO.

A very poor day 7 chart and the writing was on the wall at day 6 . Low heights to the ne phase with the Atlantic low .

No disruption at day 6 is the issue here .

A real mood sourer after the good GFS and GEM outputs .

Its questionable whether it would be able to eject the shortwave cleanly at day 7 into 8 although there is a pocket of heights to the north .

Edited March 1, 2023 by nick sussex

[seabreeze86]

Wedges starting to appear on the op runs now don’t pay much attention to where they are there sniffing something 

[NewEra21]

The past few runs the UKMO has been the worst for any longevity to this potential cold spell.

[Snowy L]

Give me the GEM please. GFS desperate to repeat the December shambles where we got a mini Euro high allowing the Atlantic in at an unfavourable angle. It's uncanny actually.

[Theresnoway]

3 minutes ago, That ECM said:

I was hoping for better tbh

I wouldn’t be too disappointed, it’s one det run 7 days out. Still all to play for in terms of potential outcomes.

[snowblind]

Just now, NewEra21 said:

The past few runs the UKMO has been the worst for any longevity to this potential cold spell.

Seems to tie in with the met office extended outlook. Snow opportunities north and east early on then milder with rain across the country after that. Low confidence on that last bit though.

[Bricriu]

The UKMO video forecasts upgrades the cold in terms of longetivity then the model downgrades it. Poor runs. We have to hope the ECM stick to its guns. 

[seabreeze86]

Just now, nick sussex said:

Oh dear what happened to the UKMO.

A very poor day 7 chart and the writing was on the wall at day 6 . Low heights to the ne phase with the Atlantic low .

No disruption at day 6 is the issue here .

A real mood sourer after the good GFS and GEM outputs .

I’m not so sure Nick about the UKMO I think it could easily turn cold again from there 

[NewEra21]

7 minutes ago, That ECM said:

I was hoping for better tbh

Definitely don't want to see too much of this amongst the ensembles of the GFS or ECM. Could go downhill quickly otherwise.

[That ECM]

3 minutes ago, Theresnoway said:

I wouldn’t be too disappointed, it’s one det run 7 days out. Still all to play for in terms of potential outcomes.

There’s time I agree but……

let’s see what ecm has to say.

[IDO]

The three models so far all indicate a breakdown around D8-11, with the UKMO being the most progressive, but quite feasible, but worst case IMHO:

So this looks like the SSW effects are short-term with the blocking pattern collapsing as the Greenland and Pacific ridge/highs slip away. Hopefully, there will be some wedges that help the cold linger a bit longer, or alternatively, we get a further SSW downwelling on the back of this.

[mulzy]

ECM was the pick this morning - it really needs to be again this evening.  Things could unravel fast here (toys and prams and all that) if ECM is poor.

[nick sussex]

2 minutes ago, seabreeze86 said:

I’m not so sure Nick about the UKMO I think it could easily turn cold again from there 

I’d rather not find out ! 

[Froze were the Days]

3 minutes ago, IDO said:

SSW downwelling on the back of this.

Another one?...the first one hasn't amounted to much, we were meant to be seeing the effects around about 2nd/3rd initially, signs not looking good for any length of cold which is not surprising, even the 2018 event although a short sharp affair managed to last 5 days or so.

Edited March 1, 2023 by Froze were the Days

[Willsy]

some very interesting output from the models the last few days. i really hope we don’t get led up the garden path again tho as has happened more than enough this winter. praying we can get these tasty charts within t24 

[Bricriu]

7 minutes ago, IDO said:

The three models so far all indicate a breakdown around D8-11, with the UKMO being the most progressive, but quite feasible, but worst case IMHO:

So this looks like the SSW effects are short-term with the blocking pattern collapsing as the Greenland and Pacific ridge/highs slip away. Hopefully, there will be some wedges that help the cold linger a bit longer, or alternatively, we get a further SSW downwelling on the back of this.

According to the Met Office deep dive video they think this is the result of the first warming two weeks ago. So if that the case, then maybe we will get another round of blocking in another two weeks from the recent warming. If it is going to be a short lived cold spell it's somewhat disappointing given we have had the ssw and  mjo phases conducive to blocking. Unless one is somehow working against the other? Could that be possible? 

Edited March 1, 2023 by Bricriu

[Johnp]

I remember the days when people wouldn’t give the time of day to the UKMO day 6 chart - and now we’re having kittens over what it shows at day 7.

The old adage always applies - get the cold in first and then see what happens. 

[NewEra21]

Just now, Willsy said:

some very interesting output from the models the last few days. i really hope we don’t get led up the garden path again tho as has happened more than enough this winter. praying we can get these tasty charts within t24 

If nothing comes of next week, the chase will be over for me. Just can't get excited from the middle of March onwards. So here's hoping next week gives us all cold and snow fix!