Model Output Discussion - 1st February Onwards 12z--->

[polar vortex]

Whilst the ECM  is rolling out I want to highlight the GEFS control.

 

 

Before anyone says I am merely highlighting the chart below towards all those posts saying "Winter is over", "No chance of snow anymore for low lying areas"!!

 

 

GEFS control.png

 

Just add how the ECM differs with regards to the low pressure in the Atlantic between +120 & +168 shows our outlook is far from certain. The ECM has this tracking SE into the Med, other models NE into Scandi!

Cracking run and looks like our most potent easterly since 91. I must admit for me when you see a 1040 mb high orientated in such a way as to allow the  bitterly cold east/ northeasterly air to push west over the UK there are very few better winter

synoptic patterns.

Edited February 6, 2015 by polar vortex

[Nouska]

Well a big change on ECM tonight. No sooner does Fergie suggest a possible low next weekend then it throws this out! Been no sign up until now on any output I dont think? Amazing

 

 

The signal was in the ensembles - I mentioned it yesterday - in reply to mushy.

 

https://forum.netweather.tv/topic/82438-model-output-discussion-1st-february-onwards-12z/?p=3166155

 

Growing support on the GEFS as well. 850 winds on the bottom graph. 

 

[Winter Cold]

The signal was in the ensembles - I mentioned it yesterday - in reply to mushy.

 

 

 

So you did. Sorry Nouska, must have missed that!

 

Nice to see growing support for something a little more interesting then in a weeks time to mix up what could be weeks of boringness. Something to keep watching anyway and its breathed a bit of life into the thread tonight

[Mucka]

I think you will find the low ends up just being centred E of Ibiza.

 

In my experience when you have one model sending a LP into the Med and other models sending this NE towards Iceland/Scandi then maybe none of the model output can be trusted and the outlook becomes rather uncertain.

 

Well it puts the cat among the pigeons to a certain extent but it has no backing from UKMO, JMA. GFS or GEM and non within GFS ensembles so on balance and given recent performance I am as close as I can be to dismissing it though it is sensible to wait until tomorrow's runs before doing so.

The GEM could be the eventual outcome, glancing blow from shallow trough but the diving low scenario looks very low probability on balance.

There is always the small chance ECM is picking up something all the other models have missed but if I had to make a forecast I wouldn't be going the ECM route.

[Summer Sun]

The ECM supports a couple of less settled days later next week before a return to settled weather

 

 

So pretty much following what Fergie said this morning where by any unsettled spell looks very transient

Edited February 6, 2015 by Summer Sun

[ANYWEATHER]

Perhaps more joyful times than we anticipated

[Nick F]

Yep, 12z ECM strikingly at odds with GFS and UKMO as earlier as t+144, which makes you wonder whether it's an outlier.

 

Looking at the jet profiles from both 12z GFS and ECM at t+168, you can see on GFS the west to east zonal jet way to the north over Iceland above a ridge centred over the UK ... while ECM has a more amplified flow over the Atlantic with the jet diving SE from Greenland down toward the Bay of Biscay with low pressure affecting the UK.

 

 

Difference seem to hinge on how the models handle the lobes of the top vortex pushing SE across Labrador/NE Canada and out towards the NW Atlantic which effect the jet stream position. ECMF pushes a lobe SE and pushes the jet south later next week.

 

The models agree on the anticyclone drifting slowly east across the UK early next week, ending up centred over northern Germany by mid-week. This allows a southeasterly flow to develop by Weds, which will feel chilly off the near continent for southern areas. After that, the models come off the rails with regards to confidence ...

Edited February 6, 2015 by Nick F

[knocker]

Indeed

Chart weatherbell

 

[shaky]

Well well more amplification on the gfs 18z in the atlantic! ! Lets see where it goes!!

[Ice Day]

Some very decent cold just off the east coast at 156.  A big change on the 18z vs 12z.  Perhaps the earlier ECM was onto something?  Let's hope so.

 

[Nick F]

Indeed

Chart weatherbell

 

Combine that mslp mean with the 12z ECMWF H500 mean and you can see the signal for a resurgence in mid-Atlantic ridging toward SE Greenland and Iceland:

 

 

NWly flow returning as has been common for much of the winter?

[blizzard81]

Some very decent cold just off the east coast at 156.  A big change on the 18z vs 12z.  Perhaps the earlier ECM was onto something?  Let's hope so.

 

If you imagine the middle ground between the 12z ECM and the 18z GFS, the frigid cold would be UK bound!

[Jason M]

It's like Groundhog Day. More amplification, better charts at day six but still a UK high.

In fairness there does seem to be a window of opportunity around day six, so it will be interesting to see if it develops any further or whether the GEFS do anything different.

[bluearmy]

.

How much would you like to be in New England next weekend?

[Eugene]

Some very decent cold just off the east coast at 156.  A big change on the 18z vs 12z.  Perhaps the earlier ECM was onto something?  Let's hope so.

 

 

 

 

Hey GFS 18Z is nothing like ECM 12Z, HP with cooler air filtering in and hopefully clearing the gloom.

[Ice Day]

If you imagine the middle ground between the 12z ECM and the 18z GFS, the frigid cold would be UK bound!

 

Yes indeed, mind you, luck's not really been on our side this winter.  Time for a last hurrah of winter yet though!

[Ice Day]

Hey GFS 18Z is nothing like ECM 12Z, HP with cooler air filtering in and hopefully clearing the gloom.

 

Similar as in greater amplification rather than the earlier flatter patterns.

[knocker]

image.jpg. image.jpg

How much would you like to be in New England next weekend?

 

Or you could try parts of Alaska which will be down to -50c in two or three days.

[igloo]

better run but this time north africa gets all the cold 

 

[bluearmy]

Or you could try parts of Alaska which will be down to -50c in two or three days.

But Alaska is supposed to be a frozen wasteland in winter. I'm talking countryside that resembles where we live .......just crazy conditions and it looks like it will keep coming through the month for them.

[igloo]

Or you could try parts of Alaska which will be down to -50c in two or three days.

it was -43c on tuesday in dawson city in the klondike a bit nippy

Edited February 6, 2015 by igloo

[Daniel*]

There's room to grow here -

Better on the 12z increased amplification to the NW

It'll probably flatten out... but some more 'pushes' and we could be onto something

[Cheshire Freeze]

Some very decent cold just off the east coast at 156.  A big change on the 18z vs 12z.  Perhaps the earlier ECM was onto something?  Let's hope so.

 

Models starting to 'flinch' already?? I guess we'll know either way over the weekend.

[knocker]

But Alaska is supposed to be a frozen wasteland in winter. I'm talking countryside that resembles where we live .......just crazy conditions and it looks like it will keep coming through the month for them.

 

Oh I agree and I posted charts in the American thread this morning to that effect. Brutal.

Edited February 6, 2015 by knocker

[Trom]

image.jpg. image.jpg

How much would you like to be in New England next weekend?

Trust me there is such a thing as too cold.  Just came back from LaCrosse Wisconsin and it was hitting -24 at night and not above -6 in the day.  I notice it's a bit warmer in the mid west right now.

 

Interesting to see the ECM evolution tonight but without any support it's hard to to believe it.  GFS also showing interest but with a very different evolution.  Leaves us in the usual area of "more runs needed" but some volatility is better than none if your looking to shift that high.