TEITS

January 10

13 minutes ago, TillyS said:

This is no ’63

Let's see. I’m in the wary camp this morning but then that’s my default as I’ve been let down sooooo many times in this country.

Anyway, on my travels again shortly. Have just booked some time in the Cairngorms next month. That should means some snow

No sadly it isn't and I would of loved to experienced it. Still have the great 1978 blizzard as my first memory. I envy your break in the Cairngorms as i've never been further N than Newcastle!

Much better 06Z with the GH extending further S.

January 10

Going to disagree with some of the posts today especially with regards to the initial N,ly and how far S this spreads.

If you remember for my location there was a lot of scatter with regards to the N,ly around 16th Jan. Now we have a solid cluster around -8C which for my location isn't bad for a N,ly. Also take note how even 11 days away the mean is still at -4C.

ECM ensembles for my location is also at -4C upto 20th Jan. This might not sound very cold but could be cold enough for snowfall, should fronts move in from the S.

Next take a look at ECM for N France. The mean suggests the operational was too far N.

So in summary. We begin with a N,ly, followed by a potential snow event next week (No idea where). Possibly turning less cold for the S before turning back colder again from the N into the following weekend with further snowfall opportunities. Into the following week i.e 21st Jan onwards the potential for an E,ly as I mentioned a few days ago. If this doesn't occur then still likely to remain on the cold side with further snowfall especially for the N as the pattern of blocking and a jet stream further S than normal looks the most likely outcome.

Just remember even during the classic winters of 63 (even though I wasn't born) at times the blocking did relent and briefly the upper temps increased but surface temps remained cold.

January 9

I don't often post in the middle of run but my word at the UKMO. Rather than backing towards the GFS it goes the other way and so does the Icon.

January 9

Have to say regardless of your location the current output is excellent and to be fair you will never get a set up that will deliver for everyone. Only the likes of 1947 do this when blocking alternates between Scandi & Greenland.

So the initial surge of cold N,lys around 14th/15th Jan looks likely despite some dodgy ECM runs a few days ago. At this stage snowfall looks limited but you never know what will develop in the N,ly flow.

Now onto my favourite part which reminds me of the late 1970s, 80s. The classic old skool situation of a blizzard for some, snow to rain for others, and then some seeing snow to rain and then back to snow again. At the moment impossible to say who will hit the jackpot but based on the current output and my own personal experiences I would say the bullseye is slightly further S than the ECM has this.

My reasoning is this. Note for my location the ECM operational is very close to the mean.

Now look for the S coast of England. This is way higher than the operational.

So the above combined with my own personal experience of these set ups suggest the main risk of heavy snow is further S with the N limit being around 30miles N of London. Subject to change though!!

Original post: https://community.netweather.tv/topic/99706-model-output-discussion-into-2024/?do=findComment&comment=5002842

January 9

6 minutes ago, Nick123 said:

For my own sanity I'm taking a break till the weekend. I dunno how you guys Do it!

Simple for me. There was a time when I used to view all model runs as they come out and view each individual ensemble member. I was also dreadfully biased towards cold weather. Now I try and take a more balanced approach to viewing the models but I also have less time to look at them like I used.

Also with all the pain and suffering in the world I tend to put the UK getting snow into perspective.

January 9

Have to say regardless of your location the current output is excellent and to be fair you will never get a set up that will deliver for everyone. Only the likes of 1947 do this when blocking alternates between Scandi & Greenland.

So the initial surge of cold N,lys around 14th/15th Jan looks likely despite some dodgy ECM runs a few days ago. At this stage snowfall looks limited but you never know what will develop in the N,ly flow.

Now onto my favourite part which reminds me of the late 1970s, 80s. The classic old skool situation of a blizzard for some, snow to rain for others, and then some seeing snow to rain and then back to snow again. At the moment impossible to say who will hit the jackpot but based on the current output and my own personal experiences I would say the bullseye is slightly further S than the ECM has this.

My reasoning is this. Note for my location the ECM operational is very close to the mean.

Now look for the S coast of England. This is way higher than the operational.

So the above combined with my own personal experience of these set ups suggest the main risk of heavy snow is further S with the N limit being around 30miles N of London. Subject to change though!!

January 7

10 minutes ago, sheikhy said:

West based nao at the end but its better than the 00z overall!!keep an eye on that little cold pool northwest greenland in future runs between 144 and 168 hours!!!!could derail everything quite a bit if it dont get absorbed further west or further east!!!!

No the ECM doesn't show a W based NAO.

Take a look at the N Hemisphere chart and note the pressure in Svalbard at +168 is 1000mb. By +240 the pressure increases to 1030mb. So the opposite is true if you run the sequence you will see the Arctic HP transfer E.

If ECM went out further I believe you would be looking at a prolonged cold spell with winds veering towards an E,ly.

January 7

Fantastic set of 12Zs. Shame the same cannot be said for some of the posts on this thread!

The date has always been around 15th Jan for the cold spell to really start and that remains the case.

January 7

Little chance to post these past 24hrs.

Overall I am happier today compared to yesterday. The swing of the pendulum has gone back towards cold especially with regards to the ECM. The uncertainty with regards to how far S the N,ly penetrates is clearly shown on the GEFS ensembles.

Note for my location on the 16th with the exception of one member they all reach at least -8C.

Now the S coast of England. Note the increased scatter for the 16th of Jan.

Northern parts of France and this scatter is even more noticeable.

Like I say the trend today has gone back towards the N,ly extending across most of the UK. Lets hope this shift S continues and who knows we may see a trend towards the N,ly being followed by an even colder E/ENE,ly towards the end of the following week i.e 20th Jan .

January 6

I have mixed feelings about the output today.

After looking at the ECM and then other output including the ensembles I am somewhat confused. Partly because despite what the ensembles say if the ECM operational strays away from the ensemble mean on successive runs then my concern is the ensembles will eventually follow the operational.

Having said this when it comes the a Greenland high pressure and the ECM then all sorts of past memories come flooding back. During 2009 & 2010 the ECM caused alot of drama by just backtracking from the projected cold spell for about 48hrs. When the cold spell returned I remember the surprised comments by a member called Ian Brown. The Greenland high caused similar drama in Dec 2010. Again the same member called Ian Brown accused me and Nick Sussex of being SE biased. This was because the ECM was sending the cold arctic blast into the Atlantic Ocean rather than the UK. Slowly the ECM backtracked to moving everything E. Always makes me laugh as Nick S doesn't even live in the UK anymore!

So my point is basically don't worry just yet but hope the ECM comes back on board. When it did during 2009, 2010 it actually massively upgraded the cold spell.

January 5

Going to be honest I am disappointed with the commentary on here these past 24hrs. So much so I couldn't be bothered to post.

Lets begin by saying some of the model output these past 24hrs has been sensational and you could not draw any better charts for the UK. I would even go as far to say the best cold weather output I have seen. So when the bar has been set so high you are bound to see less impressive runs. However even the less impressive runs will deliver what many seek.

The GEFS/ECM mean continue to be fantastic, especially the ECM.

Some people have been referring to a W based NAO. The ECM mean at +240 does the opposite as to me a W based NAO is when the blocking backs W and allows SW,lys via atlantic low pressure systems moving in. The ECM mean is extending the block even further S. The ECM even causes a low pressure in the Atlantic to move W!!

Lets also not forget the argument that all cold spells downgrade is flawed. Even recently some were suggesting the GFS would be right and we wouldn't even have an E,ly next week as low pressure was supposed to track NE into Iceland and our HP sinking over the UK.

Moving onwards and at the moment even the transitional phase from the E,ly to a Greenland block is uncertain with regards to timing and detail and won't be resolved for another 72hrs. I could spend all day typing out various scenarios beyond this for mid Jan onwards.

Overall a wintry outlook is most likely but could this be a convective N,ly or Bitter convective ENE,ly or will low pressure approach from the SW bringing a blizzard to some locations. Another option is low pressure in the atlantic phasing with the low that is moving S from the arctic, enhancing the bitter flow from the ENE.

Original post: https://community.netweather.tv/topic/99706-model-output-discussion-into-2024/?do=findComment&comment=4996050

January 5

Going to be honest I am disappointed with the commentary on here these past 24hrs. So much so I couldn't be bothered to post.

Lets begin by saying some of the model output these past 24hrs has been sensational and you could not draw any better charts for the UK. I would even go as far to say the best cold weather output I have seen. So when the bar has been set so high you are bound to see less impressive runs. However even the less impressive runs will deliver what many seek.

The GEFS/ECM mean continue to be fantastic, especially the ECM.

Some people have been referring to a W based NAO. The ECM mean at +240 does the opposite as to me a W based NAO is when the blocking backs W and allows SW,lys via atlantic low pressure systems moving in. The ECM mean is extending the block even further S. The ECM even causes a low pressure in the Atlantic to move W!!

Lets also not forget the argument that all cold spells downgrade is flawed. Even recently some were suggesting the GFS would be right and we wouldn't even have an E,ly next week as low pressure was supposed to track NE into Iceland and our HP sinking over the UK.

Moving onwards and at the moment even the transitional phase from the E,ly to a Greenland block is uncertain with regards to timing and detail and won't be resolved for another 72hrs. I could spend all day typing out various scenarios beyond this for mid Jan onwards.

Overall a wintry outlook is most likely but could this be a convective N,ly or Bitter convective ENE,ly or will low pressure approach from the SW bringing a blizzard to some locations. Another option is low pressure in the atlantic phasing with the low that is moving S from the arctic, enhancing the bitter flow from the ENE.

January 3

I am sure some newcomers must be utterly confused by reading this thread this morning. So here is my assessment of what the models actually show rather than what may go wrong.

Firstly very good agreement it will turn colder this weekend. Probably not cold enough for snow showers but still uncertain as the mean is at -8C but the ensembles vary between -5 to -10C. Regardless of snow I think many will welcome this change in our weather pattern.

Note the increase in the upper temps for next week. This is the transitional phase before we see blocking develop over Greenland. Much of next week is likely to be settled, cold, frosty but locations such as Wales, W Midlands may struggle to reach much above zero during the day. Freezing fog could be a big issue.

Now onto my favourite part and that is the following weekend 12th Jan. The GEFS/ECM mean is fantastic with regards to blocking over Greenland. A SLP mean of 1030-1035mb in Iceland is incredible and is comparable to what we witnessed prior to the 2010 cold spell.

The error that some are making is by not viewing the models from a N Hemisphere perspective. The greenland high is as a result of what is happening to the PV and pressure increasing over the Arctic. The Greenland HP isn't because of our high pressure over the UK this weekend moving into Greenland.

I shall just add that in 2010 the models made a right drama over the Greenland high and a W based NAO. For many runs they had this too far W with the low sinking S in the Atlantic rather than the UK. Thankfully as we know this was corrected E.

Original post: https://community.netweather.tv/topic/99706-model-output-discussion-into-2024/?do=findComment&comment=4992996

January 3

2 minutes ago, Kasim Awan said:

To say nothing has changed from yesterday is inaccurate, I have posted clear changes between yesterday and today's ensemble means, minor changes yes but affect the balance of the outlook slightly.

Sorry you are wrong based on the ECM.

Todays ECM mean at +216.

Yesterdays 0Z at +240.

January 3

I am sure some newcomers must be utterly confused by reading this thread this morning. So here is my assessment of what the models actually show rather than what may go wrong.

Firstly very good agreement it will turn colder this weekend. Probably not cold enough for snow showers but still uncertain as the mean is at -8C but the ensembles vary between -5 to -10C. Regardless of snow I think many will welcome this change in our weather pattern.

Note the increase in the upper temps for next week. This is the transitional phase before we see blocking develop over Greenland. Much of next week is likely to be settled, cold, frosty but locations such as Wales, W Midlands may struggle to reach much above zero during the day. Freezing fog could be a big issue.

Now onto my favourite part and that is the following weekend 12th Jan. The GEFS/ECM mean is fantastic with regards to blocking over Greenland. A SLP mean of 1030-1035mb in Iceland is incredible and is comparable to what we witnessed prior to the 2010 cold spell.

The error that some are making is by not viewing the models from a N Hemisphere perspective. The greenland high is as a result of what is happening to the PV and pressure increasing over the Arctic. The Greenland HP isn't because of our high pressure over the UK this weekend moving into Greenland.

I shall just add that in 2010 the models made a right drama over the Greenland high and a W based NAO. For many runs they had this too far W with the low sinking S in the Atlantic rather than the UK. Thankfully as we know this was corrected E.

January 2

The truth is little has changed in this mornings runs compared to yesterday. At no stage has any model suggested widespread cold upper temps or heavy convective snow showers for this weekend. The models have varied between dry and cold and cold plus maybe a few snow showers.

What the models continue to suggest is a genuine Greenland high block bringing a surge of N,lys from the 12th Jan onwards. The high pressure this weekend DOES NOT sink and remains in situ before moving NW as we see a negative AO develop.

So in summary turning colder this weekend, possibly even a few snow showers if the high pressure is far enough N. Beyond a rise in the upper temps as the high pressure begins to transfer NW. A cold, settled spell for next week followed by the chance of becoming very cold with widespread snow from the N (12th Jan onwards).

January 1

The GEM isn't surprising if you read my post last from the ECM ensemble mean.

So as it stands this weekend is the starter before the main course as we become more settled, colder. However between this weekend and next week we see a parting of the PV with a lobe heading to Canada and the other moving E into Russia. This leaves a lovely gap for the arctic HP to act as a Dyson and hoover the high pressure towards Greenland. The end result being a frigid N/NE,ly and a tanking negative AO with the ultimate blocking situation for a cold spell in the UK.

The above is subject to change but that is how it is currently looking.

January 1

Forget about the longer range. Even at +33 we have a difference between GFS and other models with regards to the track of this low. A small but significant spell of gusty winds associated as the base of this low.

GFS backtracking. Note the low to the W of Iceland.

December 31, 2023

Im encouraged with the output so far this evening. Firstly the 18Z JMA is very much on the side of the UKMO than the GFS. The most appealing model run is take a look at the N Hemisphere on the ECM ensemble mean and note what happens to the Polar Vortex between +144 to +240.

Even if the first attempt is unsuccessful I can see many further opportunities with the AO becoming more negative as we head into Jan especially mid Jan.

December 31, 2023

1 minute ago, Kasim Awan said:

ECM closer to GFS than UKMO at day 5. Let's see where it goes from here.

Except GFS has a deep low pressure around Iceland. The ECM has SLP at 1015-1020mb.

The truth is the ECM is in the middle between GFS & UKMO. Saying otherwise is either misleading or just on a wind up!

December 31, 2023

This you rarely see even at this timeframe.

My summary is simple.

As a former Chef the better the ingredients the better the main course & dessert would be. At the moment it looks as though we have some of the finest ingredients arriving. Just bloody frustrating they keep getting delayed!

December 29, 2023

On 28/12/2023 at 10:44, Kasim Awan said:

Still early days yet especially for mid January however the last 72 hours has definitely shifted the direction towards a more Atlantic setup.

Your post yesterday never made any sense to me and even more so today. This also applies to all those who suggested the Atlantic low pressure systems will dominate.

Taking into account all the model output and ensembles the trend towards high pressure of around 1030mb around the Iceland area is gaining momentum. The GEFS did backtrack from 1025mb a few days ago to 1010mb. However now the 06Z has come out I expect the GEFS mean to increase again.

December 28, 2023

9 minutes ago, Marting said:

The ECM ensembles are fairly bold this morning, continuing with that steady decline. Very different to the GEFS.

Thanks for posting this.

The massive difference in some of those 850hpa ensembles just highlights why it's pointless posting some of the mean ensemble charts for the 11th Jan.

I am still positive this morning for a big change in our weather pattern. At the moment the models are very inconsistent even on the operationals at a relatively early timeframe i.e +144. As I mentioned yesterday there is the chance that between +96 and +168 we see the low pressure systems take a more S,ly track on a more SE,ly trajectory. The ECM is already starting to show this.

So in summary I have very high confidence of a change to more settled weather. High confidence of it turning colder with snowfall either from a N,ly or NE,E,ly. Moderate confidence that we could see a prolonged, very cold spell of weather this Jan.

December 27, 2023

2 minutes ago, BartyHater said:

It’s really not…nothing is kicking off at 186hrs.

Jigsaw pieces are moving into position. The jigsaw will not be completed until around 7th Jan. Could be earlier if you read my previous post.

December 27, 2023

The best set of GEFS ensembles so far this winter. The Iceland SLP mean has now gone from 1020mb on yesterdays 0Z to 1025mb today.

Just add that whilst the 0Z outputs from yesterday might of been too progressive in bringing in the cold earlier. The outputs today could be delaying the arrival of the cold by incorrectly modelling the track of the low pressure systems. These could track further S on a more SE,ly trajectory than currently modelled.

Finally I wanted to say the post by Met4cast on the 28th September was very impressive considering the current situation we find ourselves in.

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