Model Output Discussion - Into February

[Nick F]

2 minutes ago, feb1991blizzard said:

absolute belter that, this year has got a 2013 & 2018 signature written all over it in a big thick marker pen.

When was the date of the Feb 2018 technical SSW again?

[Lukesluckybunch]

That is one hell of a run from the gfs..but the op seems to be on its own the ens are against it..how can we be excited about something developing 10+ days away..let's see what the ECM says in morning..also as I have said before the gfs shows the heights settling in the perfect position in my opinion between Iceland and Norway..and you can see what the results are!

Edited February 2, 2023 by Lukesluckybunch
Adding

[feb1991blizzard]

1 minute ago, Nick F said:

When was the date of the Feb 2018 technical SSW again?

8th feb i think - hope i am not getting mixed up with 2010.

[sundog]

Just now, feb1991blizzard said:

8th feb i think - hope i am not getting mixed up with 2010.

I think it was the 14th.

[Allseasons-Si]

8 minutes ago, feb1991blizzard said:

absolute belter that, this year has got a 2013 & 2018 signature written all over it in a big thick marker pen.

I just got giddy there Feb with you mentioning those dates,...lets hope that that name lives up to it's name

i didn't see them strat charts back in those years or i have prob forgot what they looked like,...i don't want to derail the thread but do you have those charts saved for them years?

it would be interesting if the outcome was to come to fruition like those years

i have forgot about this easterly what was forcast by the gfs but maybe later after another northery plunge(recent showings) that we may have an easterly once the trough drops down into Europe,...just a hunch as the mjo works more in our favour later in the month.

 

Edited February 2, 2023 by Allseasons-si
Added text

[feb1991blizzard]

1 minute ago, sundog said:

I think it was the 14th.

perhaps i was thinking 2010 then 

 

[Mapantz]

6 minutes ago, feb1991blizzard said:

8th feb i think - hope i am not getting mixed up with 2010.

 

5 minutes ago, sundog said:

I think it was the 14th.

 

8 minutes ago, Nick F said:

When was the date of the Feb 2018 technical SSW again?

Some pretty useful stuff here: 

Just a moment...

AGUPUBS.ONLINELIBRARY.WILEY.COM

[Daniel*]

Yes GFS forecasts in strat lately have been dramatic also some signs of a building to split. This would make some twitchy for those hoping for an early spring. 

[Allseasons-Si]

The gfs op led us down the cold garden path not up ha ha.

i mean,...seriously

[Battleground Snow]

I'm just wondering whether or not we can still get this high next week a little further north, 400-500 miles is nothing on a global scale at day 5.

Note the colder cluster around the 8th in the gefs and the jma has also pulled it a little north.

Probably will come to nothing, but something to watch on the 00z runs.

 

Edited February 3, 2023 by Battleground Snow

[Lukesluckybunch]

8 minutes ago, Battleground Snow said:

I'm just wondering whether or not we can still get this high next week a little further north, 400-500 miles is nothing on a global scale at day 5.

Note the colder cluster around the 8th in the gefs and the jma has also pulled it a little north.

Probably will come to nothing, but something to watch on the 00z runs.

 

Even with that adjustment by the JMA winds are still South southeast so not great

[Dancerwithwings]

Well that’s very nice if you don’t mind me saying 

[Battleground Snow]

4 minutes ago, Lukesluckybunch said:

Even with that adjustment by the JMA winds are still South southeast so not great

Yes it's a going to be a stretch to get the high far enough north to make the wind veer easterly, but there is just enough time for an adjustment in the next 2-3 runs

[geordiekev]

2 hours ago, feb1991blizzard said:

for the SE & London this run would be up there with the greats.

 

Are our tickets transferrable for the next journey, seeing as we didn't get our current ones stamped. Will defo be paying more attention to the postage stamps, rather than just the graphs or ops.

For instance this same date, above, has nearly every scenario going, though not sure if the UK HP showing on a fair few, actually sunk anywhere or is the same pressure as we expecting now.

Edited February 3, 2023 by geordiekev

[Kirkcaldy Weather]

15 hours ago, Kirkcaldy Weather said:

I mentioned a couple of weeks ago some similarities in the outputs then to 2018 and with that being one of the Ninà composite years that we could see similarities continue to show up, regardless whether it goes exactly like this the sheer fact of seeing such an amazingly similar run and within Day 7 is enough amazement for me

 Mean 

2018  

 

 

1 hour ago, Allseasons-si said:

Here we go,...the control going for it just like the op,this would be more plausible evolution i think, @Kirkcaldy Weather showed us the phases and it ties in with this also with heights north of the UK around Griceland.

🫡

[Mucka]

GFS bringing forward the next SSW, or does it all count as one event?

 

I still fancy some high lat blocking and a cold and possibly snowy spell 2nd half of Feb. 

 

Meanwhile GFS going for a cheeky and improbable backdoor snow event around the 10th. That is quite a tour for that cold pool.

[Mucka]

GFS ensembles trending a tad colder again?

Certainly a bit more continental flavour to the wind direction

 

It won't be the Beast or Winter wonderland but it could still give some surprise transient snow if it is right.

UKMO, Icon, GEM not remotely interested in any wintriness though

[Nick2373]

 

18z GFS once again picks the idea of something colder yesterday there was shouts of glee and high fiving when it backed down on the 12z. are we going to see a repeat? another day of  spills and frills on the GFS Rollercoaster 

 

[Vikos]

6 hours ago, Mapantz said:

 

 

Some pretty useful stuff here: 

Just a moment...

AGUPUBS.ONLINELIBRARY.WILEY.COM

The link is gold! Thank you! 
 

Abstract

A major stratospheric sudden warming (SSW) event was observed in February 2018 after a 4-year absence since the winter of 2013/2014. Based on the reanalysis data, the polar night jet changed from a very strong state to a moderate state during 12–19 January, and the moderate westerlies directly reversed to easterlies during 5–15 February. The intensified East Asian trough, Alaskan blocking, and East U.S. trough amplified the extratropical climatological wave 2, which propagated upward into the stratosphere, leading to a vortex-splitting SSW event. Predictions of the February 2018 SSW event are explored in hindcasts initialized 0–4 weeks in advance by the Beijing Climate Center Climate System Model. Less than 20% of the 28 ensemble members predict the reversal of [U]60°N, 10hPa hindcasts initialized 3 or 4 weeks in advance if a 5-day error is allowed, while this ratio increases to 43% in hindcasts initialized 1 week in advance. Based on the climatological occurrence of SSW events in the forecast system, the maximum deterministic predictable limit of this event is 1–2 weeks in this forecast system. The eddy heat flux and its domination by wave 2 can only be predicted within the predictable time limit. A comparison between hindcast members initialized 2 weeks in advance suggests that the extratropical troughs and blockings are responsible for the upward propagation of waves from the troposphere to the stratosphere. The predictable limit of the stratospheric circulation pattern for the February 2018 SSW, 1–2 weeks, also generalizes to other vortex split SSW events such as the January 2009 and February 1999 cases.

[Ali1977]

The GFS obliterated the strat at T330, the decides to heat up again by T384. Something tells me things could be properly interesting late in feb and throughout March. Have we every had a SSW on a SSW? 

[sunnijim]

14 minutes ago, Ali1977 said:

The GFS obliterated the strat at T330, the decides to heat up again by T384. Something tells me things could be properly interesting late in feb and throughout March. Have we every had a SSW on a SSW? 

Can somebody advise how long the lag time was after the SSW event in February 2018.

For some reason I have it in mind the warming had a relatively quick impact on wind reversal and effects 'on the ground' were felt as little as 10 days after the event?

We hear alot about a warming event taking up to a month to have impacts on our climate, just feel the transition in 2018 was quicker..

I might be wrong.

[Ali1977]

3 minutes ago, sunnijim said:

Can somebody advise how long the lag time was after the SSW event in February 2018.

For some reason I have it in mind the warming had a relatively quick impact on wind reversal and effects 'on the ground' were felt as little as 10 days after the event?

We hear alot about a warming event taking up to a month to have impacts on our climate, just feel the transition in 2018 was quicker..

I might be wrong.

I think the SSW happened around 12 Feb, so around 2 weeks. Whether that depends on the conditions already in place at ground level I don’t know, but it definitely depends on the type of SSW and location of the warming.

IF we do get a SSW I’m hoping for a v quick response to get the most out of it - we can still get -15c uppers into March with the perfect set up.

[Vikos]

7 minutes ago, sunnijim said:

Can somebody advise how long the lag time was after the SSW event in February 2018.

For some reason I have it in mind the warming had a relatively quick impact on wind reversal and effects 'on the ground' were felt as little as 10 days after the event?

We hear alot about a warming event taking up to a month to have impacts on our climate, just feel the transition in 2018 was quicker..

I might be wrong.

In the reanalysis, two large deceleration periods are observed before the SSW onset (12–19 January and 5–15 February). The zonal mean zonal wind is steady at ~30 m/s between the two periods. It is clear that the [U]60°N, 10hPa decelerates most rapidly in the second period. The westerlies begin to reverse to easterlies on 11 February, and the easterlies persist for more than 2 weeks. The easterlies fluctuate below the zero line from 11 to 28 February, and the maximum easterlies reach ~20 m/s on 15 February. It can be seen that the circumpolar westerlies gradually recover after 28 February.

 

Source 

Just a moment...

AGUPUBS.ONLINELIBRARY.WILEY.COM

 

[Spikey M]

17 minutes ago, sunnijim said:

Can somebody advise how long the lag time was after the SSW event in February 2018.

For some reason I have it in mind the warming had a relatively quick impact on wind reversal and effects 'on the ground' were felt as little as 10 days after the event?

We hear alot about a warming event taking up to a month to have impacts on our climate, just feel the transition in 2018 was quicker..

I might be wrong.

Depends on conditions already in place. It takes less time if it's going with the flow. 

Edited February 3, 2023 by Spikey M

[Stuie]

The UKMO overnight run for the 9th is a better looking chart for cold than the GEFS, UKMO hinting at bringing in colder air from the NW also due to better HP positioning over Scandi.

 

Edited February 3, 2023 by Stuie W