Model output discussion - Closing in on Christmas

[northwestsnow]

To be fair,this is a pretty important set of 12z runs...

Those like myself hoping GFS has this need to see UKMO esp change track at 120- 144 which is a timeframe approaching reliable ....

Fingers and toes crossed ...

[johnholmes]

To add spice to the main models, try this site. There are enough links to keep most going to Xmas!

A very interesting one for ECMWF, surface, 500mb, and 850 mb temperature information out to 10 days from its 00 and 12 Z runs

Meteorological Charts Analysis Forecast North Atlantic Europe

WWW.WEATHERCHARTS.ORG

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Meteorological weather charts, surface pressure analysis, forecast maps , satellite pictures , North Atlantic and Europe

 

 

[MATTWOLVES 3]

35 minutes ago, Jon Snow said:

Hey Matt, you are already a netweather legend..couldn’t agree with you more!..I think the models look a lot better from a cold perspective than this time last year.,(obviously)!!!..and the year before..and the year before that..etc..etc..good job mate.. I think this looks better..lol

There are plenty of colder ensembles out there still,I noticed quite a fair few from just running through half of the 30...yes I can understand some posters pointing out everything is at day 10 all the time..but like I say,we have to start somewhere. Obviously we don't want to be in a scenario where we are still eying up day 10 scenarios a month from now...the atmosphere does look more blocked this year,and for sure we have to take advantage of it sooner or later. I know some are saying we can't rely on SSW bringing us the pot of gold...but its a fact that while it does not guarantee it,a cold spell follows more often than not!! And I think I will most definitely take those odds. There is going to be some wild and fluctuating model runs in the coming few weeks...the strat guys are saying Patience is gonna be key...I have to agree with them. Let's start with some more positive 12z runs...

Ps...not so sure about Netweather Legend mate....more of a leg  end perhaps

Edited December 19, 2020 by MATTWOLVES

[Chesil View]

I particularly like P26 the trendsetting minus 15 run on the GFS 06z

[terrier]

Well it’s almost time to strap ourselves in again. We really need to see a big adjustment from the ukmo around the T120 mark. And we could do with an improvement from the Ecm later aswell. I think if the ukmo and ecm stick to there earlier parts of the output from this morning then I feel the gfs is leading us up the garden path again. Anyway not long now let’s see what occurs. 

[Mark Parsons]

23 minutes ago, Broadmayne blizzard said:

I particularly like P26 the trendsetting minus 15 run on the GFS 06z

Hey Mark long time no chat lol........Can you show that chart out of interest please bud?

[Allseasons-Si]

41 minutes ago, johnholmes said:

To add spice to the main models, try this site. There are enough links to keep most going to Xmas!

A very interesting one for ECMWF, surface, 500mb, and 850 mb temperature information out to 10 days from its 00 and 12 Z runs

Meteorological Charts Analysis Forecast North Atlantic Europe

WWW.WEATHERCHARTS.ORG

---

Meteorological weather charts, surface pressure analysis, forecast maps , satellite pictures , North Atlantic and Europe

 

 

Thanks for this John

it got me thinking that maybe there should be a separate thread with all these links to sites/models etc etc! as they would get lost in here with all the clutter and the amount of post's

seems a reasonable idea.

Edited December 19, 2020 by Allseasons-si

[Kasim Awan]

Icon has finally dropped it's unsupported Xmas evolution. 

[Ice Day]

Just before the 12z's kick off, you can see the 6z GEFS (on the left) were not quite as cold a set as the 0z (although we do see -15 uppers in for a short while), so will be interesting what the next set show.  

   

[Captain Shortwave]

Well Christmas day is now within the realms of the UKMO, so lets have a look at what might be on offer (6 days is still too far out to fully call this).

ICON

Mostly fine for most with long spells of sunshine. There is the chance of wintry showers along eastern coasts, probably areas such as Norfolk more at risk of these moving any way inland. The 2m temperatures look cold (Generally 2-4C). After some quite awful (Usually mild) Christmas days, this would be pretty decent for most, even if the vast majority do no record a "White Christmas".

Lets see what the UKMO/GFS/GEM have in store as they roll out now.

Edited December 19, 2020 by Captain Shortwave

[Ventnor Viking]

On 17/12/2020 at 17:48, Ventnor Viking said:

Looking at the latest models, it looks as though there is too much energy just west of Greenland to allow any linking or ridging to form a decent block. 

The most probable outcome based on the latest runs are that the cold spell/s will continue to be watered down. Any cold spells will be short lived and if we dont get a SSW warming then things could become more zonal when the energy from Canada/Greenland push the HP east/south east.  

I still can see this being the case. I'm sure there will be many disappointed but the NH profile as a whole looks good, but not really for us. Im sure we may see a brief cold/cooler period just before the New Year. The uppers aren't all that cold and the HP orientations just aren't good. That along with the energy just west of Greenland just won't allow for a decent set up for us to tap into anything cold. It will probably just end up being frosty mornings and wintry showers/snow in Scotland over the hills and mountains leaving the rest of us with cold and wet conditions, with the possibility of wintriness over the high ground of any fronts pushing through from the north and that's at best.  

p.s Mods this isnt a moan or to wind anyone up. Its just bringing some much needed realism into the mix. 

[Frosty.]

45 minutes ago, MATTWOLVES said:

Ps...not so sure about Netweather Legend mate....more of a leg  end perhaps

Wow buddy, I was about to give you a like but then I found out I didn’t have any?..go figure..anyway, I think the 0z / 6z has some wintry potential..or am I a liar?...you guys decide!

Edited December 19, 2020 by Jon Snow

[Daniel*]

I don’t understand why people keep saying next run will be absolutely crucial even from experienced posters it’s not like we have an easterly modelled at day 4. Things are never straightforward models drop and revert back often seen this in run up to cold spells - we should have a better idea early next week, but do not expect an answer this weekend.  

[Scott Ingham]

Quite a stark amount of extra amplification already noticeable on the GFS12z. Could we squeeze a few flurries Christmas day?

[Frosty.]

8 minutes ago, Scott Ingham said:

Could we squeeze a few flurries Christmas day?

Hmm I doubt that, but a seasonal rather chilly day for sure following an overnight frost?..I reckon Darren bett would be very upset if there was any suggestion of a flurry on crimbo day..or any other day for that matter!

Edited December 19, 2020 by Jon Snow

[iowpompeylee]

1 minute ago, Scott Ingham said:

Quite a stark amount of extra amplification already noticeable on the GFS12z. Could we squeeze a few flurries Christmas day?

This is the sort of thing I will be looking for. My main target is Xmas day and Boxing Day, now just moving into a reliable timeframe. Looking noticeably colder with the windchill too! 

[Captain Shortwave]

Day 4 

UKMO                                                                    GFS

              

 

In terms of detail for a large part of the UK, that is two completely different outcomes. The UKMO already bringing colder air through the UK, whilst the GFS as a low tracking across the south of England bring rain and potentially some strong winds. Essentially the UKMO takes more of that cold pooling (Atlantic low) southwards leaving very little to travel eastwards, whilst the GFS maintains a fully enclosed area of low pressure.

The GFS does give the potential for back edge snow on that rain band as the cold air finally pushes through (Probably needing a modest amount of height through - say 200m).

Edited December 19, 2020 by Captain Shortwave

[Mike Poole]

UKMO T144:

Looks a tad more amplified to me, from memory, slightly difficult to tell because i wasn’t expecting the T144 before the T120 and I hadn’t saved the 0z chart, and of course there is a 12 hour difference anyway.

[Scott Ingham]

2 minutes ago, Jon Snow said:

Hmm I doubt that, but a seasonal rather chilly day for sure following an overnight frost!

I imagine your right but its encouraging for the second bout of amp to know we have upgrades at short notice 

[SMU]

Afternoon >
 

24 hours ago I mentioned the possible development of a snowy trough for xmas eve ( not many picked up on it )

Its finally appeared on the GFS 108 chart > bringing some snow for Scotland

- GFS colder through 108 as well so the possibility of more snow in that low as it tracks away-

Excellent UKMO 144 seeing probable upsream amplification day 7

 

[Scott Ingham]

3 minutes ago, Steve Murr said:

Afternoon >
 

24 hours ago I mentioned the possible development of a snowy trough for xmas eve ( not many picked up on it )

Its finally appeared on the GFS 108 chart > bringing some snow for Scotland

- GFS colder through 108 as well so the possibility of more snow in that low as it tracks away-

Excellent UKMO 144 seeing probable upsream amplification day 7

 

This is a devoloping situation. I really wouldnt rule out Christmas snow Steve. Look at the uppers at 120.....

Look at how much closer the cold air is at 126 hours

Edited December 19, 2020 by Scott Ingham

[sebastiaan1973]

Excellent upgrade from UKMO. Here you see the charts for 144h. Much more meandering in the USA.

[Kasim Awan]

The icon/gfs has slightly lower heights over the North Sea during Xmas eve. Soundings are conducive for a wintry mix, with snow the main ppn type above 100m inland & in heavier bursts.

The UKMO is quite different. This macrodetail will not be fully resolved until T72.

[sheikhy]

Gfs sticking to its greenland high scenario at 150 hours?!!ukmo looks much better as well!!

[Ice Day]

4 minutes ago, Scott Ingham said:

This is a devoloping situation. I really wouldnt rule out Christmas snow Steve. Look at the uppers at 120.....

Yep, uppers are a degree or two lower than the 6z

We're always concerned about downgrades, however we could just as easily in this situation be seeing upgrades at short notice!