Model discussion: Hunt for cold - into mid-January

[Lukesluckybunch]

1 minute ago, Ali1977 said:

The UKMO is too early to show the PM flow I think, it’s beyond 168 where it kicks in on other models mainly. 

oh yes,wasnt it around 4/5th february..

[Ali1977]

6 minutes ago, Lukesluckybunch said:

oh yes,wasnt it around 4/5th february..

GFS and UKMO similar at 144, so let’s see if we can get that PM back in by day 8/9  - UKMO does look to be parting the PV a little better though.

Edited January 27, 2022 by Ali1977

[Allseasons-Si]

The UKMO at day 6(144hrs) looking good here if i am not mistaken with a more pronounced trough to the NW with tpv not as strong over N Canada allowing a better ridge into Labrador,...lets see how the UKMO 168 looks like soon.

12z 144 vs 00z 156...

 

[phil b]

On 26/01/2022 at 15:43, phil b said:

Hi Guys not sure if this has been posted, on the Wetterzentrale site you can now view the ECM charts in 3hr increments rather than the usual 24hr, shame there's not much to look at the moment!

Just an update on this, we can now see the 06z and the 18z ECM although only up to 90hrs

[Lukesluckybunch]

3 minutes ago, Allseasons-si said:

The UKMO at day 6(144hrs) looking good here if i am not mistaken with a more pronounced trough to the NW with tpv not as strong over N Canada allowing a better ridge into Labrador,...lets see how the UKMO 168 looks like soon.

12z 144 vs 00z 156...

 

it looks ok,lets not hope it turns out too west based

[Lukesluckybunch]

bit of a slower evolution on the 12z,but looks to be heading the same route!..with a horrible looking PV like that at 204h,its about the best we can hope for in terms of cold!

Edited January 27, 2022 by Lukesluckybunch
adding text

[Allseasons-Si]

UKMO 168

[Ali1977]

UKMO looking better than the GFS at 168, with a little more Atlantic amplification. The PV cut off to our north is also elongated so that should have a longer draw of colder air when it swings past.

Edited January 27, 2022 by Ali1977

[Lukesluckybunch]

omg the consistency between the 6z and 12z at 240,almost idenctical! never seen like it.thought we was in for another shot from the northwest at 240,but the low moves eastward rather then SE!

Edited January 27, 2022 by Lukesluckybunch
adding

[damianslaw]

Just now, Ali1977 said:

UKMO looking better than the GFS at 168, with a little more Atlantic amplification.

GFS heading same way though.. 

[Ali1977]

Day 10 is way in FI, last run there was a LP at Newfoundland at T270, the 12z now has a HP  at 264 . The actual charts look like that should be the other way round!! 

 

The cold associated to our NW is epic though, bring that in a PM flow at the snow would surely come!! 

Edited January 27, 2022 by Ali1977

[BLAST FROM THE PAST]

3 hours ago, bluearmy said:

The models seem to finally be moving onto the ‘wild ride’ i expected to begin a few days ago ….. it will only be about 10 days late ! 
 

whether we see this verify remains uncertain and we could still retain the displaced ridge across the south of the U.K. 

I don’t think so, it seems the first bite (LO diving NW/SE) I foresaw isn’t as pronounced but is occurring.  The second one in early Feb is getting back into favour with stormy weather and very cold northerlies to follow.  This is the zone of pattern change to allow some decent cold spell to take hold latter half of Feb.   I’m pretty optimistic right now and I think NE to E’ly flow will persevere the latter half.  It’s a little ramp but I’m liking very much what I’m seeing (but I’ll water down the depth of cold as the storminess isn’t looking as potentially severe as I thought).

 

BFTP 

[Ali1977]

The pressure charts looks fairly innocuous, but here comes that frigid PM air. 

 

Edited January 27, 2022 by Ali1977

[Ali1977]

FI, but that’s a good looking NH going forward. Look at that WAA blasting in from Alaska

[damianslaw]

All the forcing coming from the Polar Vortex to the NW and its interaction with the jetstream. Fine margins but there is a strong chance some of its frigid cold will be ebbed our way..

[Kasim Awan]

6 hours ago, northwestsnow said:

The likes of @Kasim Awanamongst others must be a bit more excited this morning.

Lots of cold PM shots on offer which will be good for those with altitude exposed to NW winds ..

Yes this has potential.

[Mapantz]

10 minutes ago, Ali1977 said:

FI, but that’s a good looking NH going forward. Look at that WAA blasting in from Alaska

Reminds me of charts  back in January 2014.. WAA in a similar place..

[Kasim Awan]

28 minutes ago, Mapantz said:

Reminds me of charts  back in January 2014.. WAA in a similar place..

So not great going forward then.

Edited January 27, 2022 by Kasim Awan

[Summer8906]

1 hour ago, Lukesluckybunch said:

UKMO not too bad,but that azores high is a feature at 144! we need that sinking south!

Would we want an Azores high to go south for cold weather? Migrating north would be better I'd have thought: if an Azores high becomes a mid-Atlantic high then we might be in with the chance for some northerlies.

Edited January 27, 2022 by Summer8906

[Summer8906]

1 hour ago, Stu_London said:

Looks like the model output discussion has sprung back into life spurred on by some improvements (from a cold perspective) to this morning's model output.

Still all in FI and the nature of cold zonality is that favoured spots tend to do well, whereas a lot areas do not either because they are too sheltered or more likely to the south, some marginality creeps in.

I, for one, will welcome the change from anticyclonic gloom that seems to have gone for ever.

 

Yes, for down here "cold zonality" is usually an oxymoron in winter; setups described as such are almost invariably wet and not particularly cold, indeed rather milder than average.To get cold weather out of an 'Atlantic' setup we need strong meridionality, a NW-SE path to the lows at the very least, something like late January 2015.

Edited January 27, 2022 by Summer8906

[Stu_London]

For me, a bog-standard north westerly in winter will often bring in uppers of -5C to -7C, maybe a touch lower briefly. However this set up looks a bit colder than this and some of the ensembles are significantly colder, so potentially an interesting set up, albeit a long way from verifying at present.

[Summerstorm]

12 minutes ago, Summer8906 said:

Would we want an Azores high to go south for cold weather? Migrating north would be better I'd have thought: if an Azores high becomes a mid-Atlantic high then we might be in with the chance for some northerlies.

Usually yes however given the current parameters this can't happen as the PV is too strong. Plus we've already had multiple attempts at this evolution. So at this juncture it going south and resetting the pattern is much better if we can tap into the cold Polar Maritime air from a NW direction. 

Maybe then down the road we could benefit from an Arctic High as Any ridging attempts towards Scandi/Greenland will likely be flattened out by the strong jet stream. 

 

 

Edited January 27, 2022 by Summerstorm

[damianslaw]

35 minutes ago, Mapantz said:

Reminds me of charts  back in January 2014.. WAA in a similar place..

Do you mean 1984 or 2015, similarities with them rather than 2014. Yes possibly a potent shot of polar maritime air on the cards from 4th Feb onwards, still over a week though..  let's see if ECM continues the theme.

[Summer8906]

20 minutes ago, Summerstorm said:

Usually yes however given the current parameters this can't happen as the PV is too strong. Plus we've already had multiple attempts at this evolution. So at this juncture it going south and resetting the pattern is much better if we can tap into the cold Polar Maritime air from a NW direction. 

Maybe then down the road we could benefit from an Arctic High as Any ridging attempts towards Scandi/Greenland will likely be flattened out by the strong jet stream. 

 

 

So in essence we have to transition through a period of more cyclonic before we can have a chance at cold, as the jet stream has to sink south over us first before it can go further south still?

Danger I guess from that is the jet stream just gets stuck over us and we just end up, particularly down here, with much wind and rain?

Edited January 27, 2022 by Summer8906

[carinthian]

22 minutes ago, Summer8906 said:

So in essence we have to transition through a period of more cyclonic before we can have a chance at cold, as the jet stream has to sink south over us first before it can go further south still?

Danger I guess from that is the jet stream just gets stuck over us and we just end up, particularly down here, with much wind and rain?

Yep, the forecast Jet shown on the UKMO extended remains zonal. Pm air mass will be modified especially for Southern Britain. Colder uppers into the Northern half, although not especially cold at this stage would be lower enough for some wintry precipitation on the hills over Northern United Kingdom.  Very difficult to forecast 850mb temps that far out though. 

C