Model Output Discussion - Spring Has Sprung

[blizzard81]

 Kasim Awan I see things differently. The cold week 2 weeks ago was modelled very similarly to this potential upcoming cold spell. The models were very undecided as to whether the cold push from the north would make it down across the country. At many stages it only looked like northern Scotland would go cold. Lots of toing and froing on the exact extent of the southward projection of cold from model run to model run. Those in the south were especially (and understandably) angst ridden about it. They were worried it wouldn't be cold enough for that azores low incoming to give that much needed snow fix. What happened in the end? The cold flooded down with ease - which ended any hopes of that azores low delivering as it was kept well south. This is what I expect this time round too - a classic repeating pattern. The cold will sweep in due south/south westwards. However with one important difference - heights lowering much more to our south. Not the bowling ball azores low type though - more disrupted. The other potentially important difference will be the all important wedge cutting down through Iceland. This is something we sadly lacked during the mid January cold snap. This feature will be crucial and it's just about getting into the mid range of all outputs now. 

[Lukesluckybunch]

192 is a real joke in the 18z..east of the uk it's a real freeze up!and we are left with mild southwesterlies!

[Metwatch]

Polar jetstream moving over the northern fringes of the Sahara, and temperatures in most of central - eastern England still managing to just about touch the double digits

The inconsistency from run to run on the dets is hilarious, but is to be expected at that time frame... Still all to play for.

Edited January 30 by Metwatch

[damianslaw]

The GFS runs often fall into the following camps :

0z run - most progressive and zonal

6z - most least progressive and amplified

12z - often a toned down version of 6z or most closely aligned to it

18z - the wild child, flips from extreme to another

Today - a great example of the above.

[Duane S.]

A very positive day from a coldy’s POV. 

Eastern Pacific activity showing up is now on the charts downstream.

Slow erosion of EU heights definitely trending.

Even the Wedge option gaining some traction. Although, personally, I don’t think cold will arrive via this route.

 

 

 

[northwestsnow]

UKMO /GEM 168

GEM then goes on to produce a snowfest at 192 onwards

GFS is rubbish but looks the odd one out at 168

[northwestsnow]

FWIW GEFS control and mean follow the op.

Hoping GFS/GEFS are hopelessly wrong.

[DavidS]

I’m quite liking the ICON at 180 this morning. It maintains a wedge of heights to the NNW and we go colder. Looks a bit on its own at that time frame though

[SLEETY]

The high pressure to the South of the uk dominating the weather, some wild weather in Norway because of it. 

Turning very mild, another very mild opening to Feb incoming. 

Watch the heights to the South magically vanish though once march onwards arrives again....

Edited January 31 by SLEETY

[Dennis]

see the KMA

interesting from 10th

scandi pressure rises

BOMM MJO

Edited January 31 by Dennis

[IDO]

I am still not seeing anything too interesting in the next ten days, but there are possibilities as we head towards mid-February, maybe the last chance saloon.

The GEM mean at D16 is the paradigm for a cold spell: upstream Alaskan ridge and the corresponding Atlantic push:

The GEFS mean is not quite there yet at that time scale but sees the Alashan amplification:

The upcoming eight days for London looking dry and relatively mild:

After that, a trough attempts to sink south/SE but is thwarted by a rising Azore/Iberian High (mean D8-15):

Maybe some westerly-based wishy-washy 850s from that outcome.

 

[northwestsnow]

EC v GFS day 8

 

[Gowon]

 northwestsnow Preferred last nights wedge over Iceland, but it'll do:

[northwestsnow]

 Gowon

Regardless GFS is the village idiot this morning...

[northwestsnow]

Day 10 

its going one way ...and a good way ..

[Lukesluckybunch]

Horrible ecm ..with fairly decent sypnotics,we still end up on the wrong side..I mentioned it yesterday,we need trough disruption..to set up a slider like possibility

[northwestsnow]

Wz gives a good picture 

cold incoming

..

[Lukesluckybunch]

2 minutes ago, northwestsnow said:

its going one way ...and a good way ..

I'm not sure about that nw..looks mild and wet to me

[northwestsnow]

 Lukesluckybunch

It is mild and wet ..

I'm talking about the evolution

 

 

[Lukesluckybunch]

4 minutes ago, northwestsnow said:

It is mild and wet ..

I'm talking about the evolution

I would say 50/50 after day 10..centre of the low,still a bit too far north..my opinionbut the cold air over Scandi doesn't really budge,which is a good thing!

Edited January 31 by Lukesluckybunch
Adding

[That ECM]

T240 for me gfs is the least appealing from a cold perspective. The other two have possibilities especially for some parts of the country. Too much that is unresolved at this time so we will have to wait to see what looks like the way forward. Need some things to fall right please.

[Lukesluckybunch]

Ecm mean very much like the op..awful!

[IDO]

The ECM mean is similar to GEFS:

850 ensembles for EC for the next ten days, also similar to GFS, so some level of consistency in the means:

 

[Chesil View]

 Lukesluckybunch  IDO

Lot of where to flow under the bridge before the 10th Feb

[Gowon]

All the models are evolving the same way this morning from the NH perspective. It's whether the jet can be forced further south, otherwise the low blows up over us. 

 

Edited January 31 by Gowon