Model output discussion - Jan 3rd onwards

[DavidS]

I think the ECM is still interesting from a NHP point of view. I like the way, the vortex is moving west to east.  This has been a theme of late.

Images are 48hr intervals out to D10

 

 

[Paul_1978]

One thing that I have been doing more of in the last couple of days is looking at the Northern Hemisphere view on the charts rather than the Europe view. The reason being is that obviously we need to be looking for signs of a "reverse" flow over the Pole, ie signs that the SSW has permeated to the Trop.

To me (and I might be reading this wrong), on the GFS a reverse flow doesn't even get going within 200 hours, and even then it's nothing to write home about. Only approaching 300 hours is there a flow that might have a bit of meat on the bones over the Pole. 

The ECM doesn't even get anything remotely looking like a reverse flow until T+240, and also nothing to write home about. I am sure the models are aware of the goings-on in the Strat, so there is perhaps a longer lag time for things to start affecting the Trop. Patience is the key. It is only 4th Jan, it's not as if we are at the end of winter - we haven't even entered the heart of winter yet!

Like I say, I might be looking at this the wrong way - but now that the SSW is starting to kick in, we should hopefully start seeing some better "reverse flows" over the Pole on the NH view of the models, and then what impact there might be on north west Europe.

Edited January 4, 2021 by Paul_1978
typo

[DanDorsetUK]

Looking at how fast its filtering down personally i cant see anything but a quick response. High latitude blocking will be evident by next Sunday mark my words. All i can see is the probability of high pressure over the pole, cold rushing into Europe and America a long fetch eastily with new wave 1 showing this morning on top to see us through February.

All looking good in my book.

[johnholmes]

1 hour ago, fromey said:

10hpa and 30hpa going up nicely 

Some years ago when I tried using this as an indicator of a possible cold spell for the UK, on occasions when it did happen, the time scale was about 12-15 days.

[festivalking]

16 minutes ago, ryanoroo said:

It would seem that back in 2018 post SSW the gfs picked up on the BFTE 12 days before (modelled it 13th and hit us around the 25th) it hit our little island... might mean nothing but worth keeping an eye on what the gfs is saying in the coming days ?

I seem to remember ICON led the way before the others fell into line. The only time I can remember ICON had its moment in the sun!!

[ryanoroo]

1 minute ago, festivalking said:

I seem to remember ICON led the way before the others fell into line. The only time I can remember ICON had its moment in the sun!!

Haha! indeed, got onto that bit in the subsequent threads of the beast arriving! Think it kinda went... gfs saw it 1st... ecm smoothed out the details and the ICON nailed it (as such) atmospherically!

[Battleground Snow]

GFS increasing the Arctic heights once more 156 v 162. The deeper the AO goes negative the better.

 

[Battleground Snow]

5 hours ago, John88B said:

Hi, a question from a complete novice. So is the SSW affecting the models already even though it hasn't actually occurred yet? Or has it occurred? Sorry really confused. Thanks in advance.

Hi John.

Sorry I didn't reply, earlier. Work is getting in the way of model watching again now!

I am novice too, the warming has occurred, we should see a technical SSW by tomorrow. I believe the models are being affected now due to the swings run to run in the 120-192 timeframe.

 

[Lukesluckybunch]

Looking for a wedge around Iceland on the 06z around 180h

[Methuselah]

A nice push of warm Uppers, into SE Europe. Again... Something which, I think, has gotten more common during our winters -- especially since 2019?

    

Now back to SSW watch!

[sebastiaan1973]

19 minutes ago, Paul_1978 said:

One thing that I have been doing more of in the last couple of days is looking at the Northern Hemisphere view on the charts rather than the Europe view. The reason being is that obviously we need to be looking for signs of a "reverse" flow over the Pole, ie signs that the SSW has permeated to the Trop.

To me (and I might be reading this wrong), on the GFS a reverse flow doesn't even get going within 200 hours, and even then it's nothing to write home about. Only approaching 300 hours is there a flow that might have a bit of meat on the bones over the Pole. 

The ECM doesn't even get anything remotely looking like a reverse flow until T+240, and also nothing to write home about. I am sure the models are aware of the goings-on in the Strat, so there is perhaps a longer lag time for things to start affecting the Trop. Patience is the key. It is only 4th Jan, it's not as if we are at the end of winter - we haven't even entered the heart of winter yet!

Like I say, I might be looking at this the wrong way - but now that the SSW is starting to kick in, we should hopefully start seeing some better "reverse flows" over the Pole on the NH view of the models, and then what impact there might be on north west Europe.

Well, it seems to me that the downwelling is not going as wished (GFS wise)

[fromey]

7 minutes ago, johnholmes said:

Some years ago when I tried using this as an indicator of a possible cold spell for the UK, on occasions when it did happen, the time scale was about 12-15 days.

Thanks John, I’m not using it as an indicator for a cold spell for the uk, just showing what’s going on up above us.

I find it fascinating and we still know very little about it. 

[feb1991blizzard]

4 minutes ago, sebastiaan1973 said:

Well, it seems to me that the downwelling is not going as wished (GFS wise)

I still think it will take that second period of -ve zonal winds at the top to start seeing the stellar charts, one problem though is there looks to be a wave near the UK in the strat on the GFS, i just hope that doesn't transpire into residual shortwave energy in the trop stretching from southern Greenland to UK but have a big fear of this happening now.

Edited January 4, 2021 by feb1991blizzard

[chris55]

SSW can take time to impact the lower levels. Two to four weeks is normal. I would say a quick response would be the 10-14 day period. 
 

So if the technical SSW is happening around now/tomorrow and we see a quick response you’d hope to see the far reaches of ECM and GfS FI picking up hints in the operational runs towards the end of the working week. 
 

Could be a painful/enjoyable period coming up  

[Weathizard]

HP nearby the U.K. seems the form horse in the medium range, albeit we aren’t sure of the ground conditions yet (SSW impact?) and so the said horse might end up in a Tesco burger.

 

There’s just too much annoying residual energy around the GL area, one thing is for sure if we don’t get any cold spell this January it will be a truly remarkable feat of bad luck, although that seems like the usual for most of us nowadays  

[Scott Ingham]

1 hour ago, bluearmy said:

 

Yes it was - saves him commenting until the next set of runs are out ....

just checked out the eps clusters and beyond day 5/6, the system dropping se into scandi may end up closer to the U.K. with less ridging across nw Europe in general 

there are enough northerly clusters with the ridging held a little to our west to maintain momentum on here ....

Certainly.

A level head is still needed 

No one should be proclaiming a bfte right now just as no one should be saying 36 hours of model runs mean its turning mild.

I still believe we could see a more middle ground where the high pressure moves further away to the west than is being shown and the previous runs being a blip

Theres certainly some small momentum building in the clusters for a reversal of the warm theme now.

On the fence i stay!

See you all after the ECM!

[PiscesStar]

3 minutes ago, chris55 said:

SSW can take time to impact the lower levels. Two to four weeks is normal. I would say a quick response would be the 10-14 day period. 
 

So if the technical SSW is happening around now/tomorrow and we see a quick response you’d hope to see the far reaches of ECM and GfS FI picking up hints in the operational runs towards the end of the working week. 
 

Could be a painful/enjoyable period coming up  

 Summed up and my thoughts exactly 

[Skullzrulerz]

NAO starting to go into two groups while one goes back to just around negative while the other remains negative 

AO more scattered though only two members go above to postives the majority remains below negative

[Scott Ingham]

46 minutes ago, Weather-history said:

Its subtle but the Manchester ECM 2m temp ensembles 

12z run yesterday                            0z run today 

Yeah evidence is stacking of an over reaction unitially from the models to send the high over NW Europe.

Big runs this evening

[Cavehill Snow]

32 minutes ago, Paul_1978 said:

 

The ECM doesn't even get anything remotely looking like a reverse flow until T+240, and also nothing to write home about. 

 

I am mystified by this also - i acknowledge that many are looking for a cold / snowy outcome for our neck of the woods, but what i am perplexed by is that there will be much less high latitude blocking anywhere in the northern hemisphere @240 hrs compared to what we have seen over the last week.

[That ECM]

The thing about this run thus far is the heights to the ne. Have a look at the mean and the perts. Also right over the North Pole. 

Edited January 4, 2021 by That ECM

[feb1991blizzard]

[bluearmy]

5 minutes ago, feb1991blizzard said:

You’d be surprised to see that particular solution repeat ...... could be worse - might be three hundred miles to our west ! 

[wellington boot]

20 minutes ago, Scott Ingham said:

Certainly.

A level head is still needed 

No one should be proclaiming a bfte right now just as no one should be saying 36 hours of model runs mean its turning mild.

I still believe we could see a more middle ground where the high pressure moves further away to the west than is being shown and the previous runs being a blip

Theres certainly some small momentum building in the clusters for a reversal of the warm theme now.

On the fence i stay!

See you all after the ECM!

Hey get off that fence! You have been emphatically in the cold camp, rejected models suggesting a warm up, insisted it would stay blocked and cold.

And I for one hope you are right.

[nick sussex]

Almost but not quite there on the GFS06 her run .

The trigger shortwave ejected off the main upstream low around day 7 is certainly something to keep an eye on.

We need a bit more cut back sw wards in the jet and more amplification upstream but it’s not a big leap of faith within the current evolution .