Model output discussion - Closing in on Christmas

[Skullzrulerz]

58 minutes ago, mountain shadow said:

If the ECM is closer to being correct with the failed and flatter ridge towards Greenland before Christmas,  then this would be yet another abject failure of the models, particularly the GFS to accurately model the energy leaving the US Eastern seaboard.

This is why I'm a jam tomorrow guy.

The ECM could be wrong of course, but once the downgrades start there's usually no way back.

As a positive,  Christmas looks seasonal with the chance of flurries of snow in the North over hills and mountains. 

Not sure why you think ECM has "failed"? It could turn out to be correct for all we know

This is why I have been saying the last few days to not get excited as it's still out of the reliable timeframe and we all know on here it most likely gets down graded beforehand 

[sheikhy]

12 minutes ago, mb018538 said:

ECM Op was a bit aggressive with the low this morning. Longer range clusters are a bit of a mess too.







 

They keep changing every run at the moment though mate!!!a joke really!just yesterday on the 12z they were fantastic!!but as they are available its one of those things that we just take a look at lol!!

[Vikos]

One scenario that could possibly happen in my oppinion...

[joggs]

Just now, Vikos said:

One scenario that could possibly happen in my oppinion...

100000/1 shot for our tiny Island

[Radiating Dendrite]

1 minute ago, sheikhy said:

They keep changing every run at the moment though mate!!!a joke really!just yesterday on the 12z they were fantastic!!but as they are available its one of those things that we just take a look at lol!!

But they will always chop and change past +144 - they are essentially weighing up solutions and averages, it does not take much to tip them into a different direction. The trend is always your friend and I would still say we are looking cold from Christmas to NY, but I would class it more as chilly rather than bone chilling.

[mb018538]

3 minutes ago, sheikhy said:

They keep changing every run at the moment though mate!!!a joke really!just yesterday on the 12z they were fantastic!!but as they are available its one of those things that we just take a look at lol!!

My worry is that they are over-egging any Atlantic amplification...and that closer to the time low pressure will exert more influence and flatten everything out, leading us nowhere.

[I remember Atlantic 252]

2 minutes ago, mb018538 said:

My worry is that they are over-egging any Atlantic amplification...and that closer to the time low pressure will exert more influence and flatten everything out, leading us nowhere.

99% chance for our island

[Vikos]

1 minute ago, mb018538 said:

My worry is that they are over-egging any Atlantic amplification...and that closer to the time low pressure will exert more influence and flatten everything out, leading us nowhere.

I smell that atlantic bias in the modells. I hope, that once the ridge stands, it will be strong enough to wuthstand the atlantic, since there is not really a lot of cold over canada to engage an active AO/NAO atm.

[Kentish Snowman in Yorks]

Nice set of GFS ensembles in table form this morning.

These are for my location but look just about the coldest set yet in respect of this potential cold spell....

Starting to see more sub -9 and -10 runs towards extreme FI too.  Could be nothing but better to see those runs than not....

Edited December 15, 2020 by Kentish Snowman

[northwestsnow]

Still in the game for a cold Christmas ...

EC det is freezing cold on Christmas Eve ..

Mean supportive of a cold High for the big day ....

I do agree things look a bit flatter this morning,esp EC and its mean ,don't want to see things flatten out further but at the range involved it is entirely possible 

Clusters still look good to me ...

[Daniel]

2 minutes ago, northwestsnow said:

Still in the game for a cold Christmas ...

EC det is freezing cold on Christmas Eve ..

Mean supportive of a cold High for the big day ....

I do agree things look a bit flatter this morning,esp EC and its mean ,don't want to see things flatten out further but at the range involved it is entirely possible 

Clusters still look good to me ...

2m temps for Christmas eve 

[Weather vane]

Some good cross model agreement for seasonal cool weather around xmas day.  Looking at Nao forecasts for longer term cold hints, there is support for soon heading into negative territory (we"ve been near neutral for a while now). However, forecasts for the linked MJO is to stay stubbornly in phase 5, and not enter stages 6-8 (favours neg Nao).

[Radiating Dendrite]

Just now, Weather vane said:

Some good cross model agreement for seasonal cool weather around xmas day.  Looking at Nao forecasts for longer term cold hints, there is support for soon heading into negative territory (we"ve been near neutral for a while now). However, forecasts for the linked MJO is to stay stubbornly in phase 5, and not enter stages 6-8 (favours neg Nao).

Has there been a change in the MJO the last few winters? It feels like it is forever low amplitude and often in the COD. Is climate change driving something here?

[northwestsnow]

5 minutes ago, Daniel said:

2m temps for Christmas eve 

Looked colder on weather.us but I would hazard a guess temps would plummet overnight....

[blizzard81]

I'm just hoping for some seasonal weather for now. The amount of rain up here is just beyond the joke now. I certainly don't 'feel' like the cold that is forecast will be long lasting aka EC46. Looks like a glorified toppler that will provide some nice crisp weather. 

[northwestsnow]

If only the mjo could help us out we would be laughing right now, EC looks reluctant to get into higher amplitude phase 6 , I wonder if this might be tied into the flatter output from its suite this morning ...

Edited December 15, 2020 by northwestsnow

[mb018538]

5 minutes ago, Radiating Dendrite said:

Has there been a change in the MJO the last few winters? It feels like it is forever low amplitude and often in the COD. Is climate change driving something here?

I know @Radiating Dendrite. There were hints of a move into 7/8/1 earlier into December, but yesterdays update has us firmly back in the COD. No MJO help yet again it would seem, and a long cycle to have any chance of 7/8/1 again.

[Skullzrulerz]

5 minutes ago, northwestsnow said:

If only the mjo could help us out we would be laughing right now, EC looks reluctant to get into higher amplitude phase 6 , I wonder if this might be tied into the flatter output from its suite this morning ...

Indeed and will probably be only time till the GFS joins as well

Though with the recent updates it does look like the AO/NAO does go into negative values for some time 

[Weather vane]

14 minutes ago, Radiating Dendrite said:

Has there been a change in the MJO the last few winters? It feels like it is forever low amplitude and often in the COD. Is climate change driving something here?

This article published in Nature has lots of info on climate warming and the MJO.

Madden–Julian_oscillation_chan.pdf

[Guest]

Read this forum this morning thinking 'ooh something colder coming' looked at the detail and for at least the next 7-8days it looks like I'll see maxes into double digits. Clearly hope still being pinned FI.....

Edited December 15, 2020 by Guest

[tight isobar]

Depending on ya views/-what occalation you prefer..and singular members for orbit!!. Is always a million miles from 1/to the other interpretation..     gage the mjo.. then revert to geopotential 500,s.. and compare within the time given @december late...   the orbit stamped.. can be 1 member converting...   in simple terms.. look at geopotential heights... then take the madden oscillations, as background noise..!!!! All imo ... but worthy..   @classic blocking.. and potential..@ pun intended

Edited December 15, 2020 by tight isobar

[chris55]

Christmas Day Channel low on the GFS Control! Oh go on then   ️ 

 

Spaghetti also looking colder, the initial mild hump has all but disappeared (looking at the average)

 

Again it’s the modelling of the initial Atlantic Low that is proving tricky. GFS vs ECM 168

GFS separating the energy and dissipating it while ECM revs it up and that helps to ‘pull’ the pattern east flattening things a bit more.

 

Both perfectly feasible options. Lets hope GFS has this right. 

[TSNWK]

4 minutes ago, tight isobar said:

Depending on ya views/-what occalation you prefer..and singular memebers for orbit!!. Is always a million miles from 1/to the other interpretation..     gage the mjo.. then revert to geopotential 500,s.. and compare within the time given @december late...   the orbit stamped.. can be 1 member converting...   in simple terms.. look at geopotential heights... then take the madden oscillations, as background noise..!!!! All imo ... but worthy..

Thanks! I think

[tight isobar]

9 minutes ago, TSNWK said:

Thanks! I think

I’ve corrected the spelling @members that should clear your pathway??!

[Anthony Burden]

Still a few days to run before we nail down the exact set up regarding how this up and coming 

cold snap or period unfolds.As I mentioned before the high pressure is the key for cold lovers 

the position and orientation and how long it lasts to divert the low pressure systems to keep

us under a cold air supply.