Model Output Discussion 01/09/17

[January Snowstorm]

Certainly for my area and the West in general it looks cold and frosty with very little ppn. ......frost likely to persist through the day by mid week.  I understand why you guys in UK are excited being closer to the low pressure

[Derecho]

Looks like another build of SLP around Greenland, the Azores low means that I can't see a return to zonal anytime soon.

[Singularity]

12z UKMO. Hmm. That low N of Iceland needs to split cleanly from the Canadian lobe for this to go anywhere particularly enticing.


Meanwhile GFS has the Canadian low heights so much further west that having had little lows sneaking across Greenland has not mattered, in fact it's being turned in our favour by the looks of it via a new round of height building in the N. Atlantic.

Question is whether UKMO's positioning of the Canadian low heights is old news with the model lagging behind, if GFS' new idea is just a flight of fancy; a fluctuation in what happened to be a nice direction? That it fits to some extent with the 00z ECM reduces the chances of this, but even so, UKMO makes me wary of any expectations of a prolonged or (at least very) quickly reloading cold spell.

[karlos1983]

Here she comes, heights building north again

Edited November 25, 2017 by karlos1983

[swfc]

To be honest up to 190hrs gfs really is a shambles in its consistency imo

Cold outlook granted,which direction no idea!!!

[SLEETY]

Wretched UKMO run  hope ECM better

[northwestsnow]

1 minute ago, SLEETY said:

Wretched UKMO run  hope ECM better

Agreed...ukmo model starting to get on my wick now...was great this morning now its gone and chucked out a poor run...

[terrier]

Well it’s all abit meh tonight so far. Gfs flipping about like a fish out of water upto t190. The ukmo is a worry and seems to match the extended outlook last night from the met. So next week looks cold and frosty with few wintry flurries. Where we go from here who knows. Let’s hope the ecm can shed some more light later. Just hope it doesn’t follow the ukmo. 

[damianslaw]

Overall theme from all models if for generally cold conditions to persist, with a blocked atlantic. GFS and ECM suggesting re-building heights in the vicinity of Greenland and a significant arctic high, with mid atlantic ridge development - if the three combine then a very cold wintry outlook could eventually develop, but as shown by UKMO shortwave development could scupper it. What I can't see from any of the models is a swift return to atlantic zonal stuff anytime soon. Keep an eye on developments over NE USA as it is here where the key lies to developments our way through early December. We are in an excellent synoptical set up for quite a sustained colder period, how cold remains to be seen.

Happy to see the fells covered in snow today, indeed there was snow down to 150 metres this morning. 

[Summer Sun]

UKMO has the coldest air slipping away as we move towards winter still no sign of any Atlantic lows though so remaining chilly

 

[bluearmy]

Some of the gefs members have developed a west based neg NAO in week 2 - maybe this op will do similar ??

the transition between amplifications is uncertain but gfs 12z isn’t too far from ecm 00z so that would seem to be a decent call at present 

 

 

Edited November 25, 2017 by bluearmy

[Mucka]

There is an element of the models trying to snatch defeat from the jaws of victory this afternoon but I suspect ECM will restore the faith.

There is still a lot of variation in how blocking will develop and take hold but the main thing is blocking is still strongly modelled throughout.

We may well just be seeing worse case scenarios which themselves seem to be slow burners to a possible deeper cold setup.

And we are guaranteed at least a cold spell to come so not too concerned at the moment - just the normal run to run ebb and flow.

Also GFS is BS from 192. (not just because it is FI but the way it develops a bowling ball secondary trough to pump up Euro heights.

Edited November 25, 2017 by Mucka

[That ECM]

Funny how we can view things differently. I am not disappointed in this, it's where you see the high going form there I guess. Happy for others to disagree, it's all part of the fascination.

[Met4Cast]

UKMO - Yuck. It makes a mess of a shortwave and as a result, poor blocking. UKMO has been all over the shop

GFS - Good. Differing solutions for the extended but overall theme for a continuation of blocked/cold is still very much there

ECM - Ideally we want to see it follow the GFS and tell the UKMO to step up it's game. This mornings ECM clusters/ensembles were very good.

 

Very cold next week, slight easing of cold thereafter as the high orientates itself. (hopefully back towards Greenland) We have 6-7 days of guaranteed cold weather with snow likely cropping up at short notice. The FAX charts will be key, look for toughs/small wave like features in the unstable flow.

 

Edited November 25, 2017 by Daniel Smith

[Tracy Flick]

GFS and UKMO aren't really that different, locally at least. The UKMO high is slightly farther south, but I doubt it's critical in the grand scheme of things going forward(?):

[swfc]

So now At 240hrs heigths building to the south stopping pressure falling???haha 

[Ice Day]

The 12z's are a little underwhelming in comparison to this mornings output, but the reliable time-frame is still looking very good for most of the UK.  It will be interesting to see if the ECM sticks to its guns tonight.  Back here at 6.00 for the next gripping instalment!

[Summer Sun]

GEM slowly get's less cold as we move into winter ending with a westerly

Over to ECM now

[SLEETY]

Gfs gets cold again at the end,buts it’s a complete mess before then.Over to Ecm for the next round of fun 

[feb1991blizzard]

Whatever strat warming we were talking about earlier, the main thing is its still there on the 12z, only good news so far from the 12z's

[Frosty.]

Lots of increasingly wintry weather next week on the Gfs 12z with the midweek period seeing a risk of snow just about anywhere as arctic air digs south..these are great charts from a coldies point of view for the end of autumn..biting cold Northerly winds for a time next week with snow showers across exposed northern and eastern areas, even the southeast seeing some snow on this run..hope we do get these colder uppers to support wintry ppn!frosty, icy and for some, snowy through most of next week according to this!

[snowstorm445]

GFS certainly remains very chilly towards the end of the run, although the Synoptics are a bit of a mess with a very weak Greenland high setting up alongside the Azores high.

[Day 10]

16 minutes ago, Mucka said:

There is an element of the models trying to snatch defeat from the jaws of victory this afternoon but I suspect ECM will restore the faith.

There is still a lot of variation in how blocking will develop and take hold but the main thing is blocking is still strongly modelled throughout.

We may well just be seeing worse case scenarios which themselves seem to be slow burners to a possible deeper cold setup.

And we are guaranteed at least a cold spell to come so not too concerned at the moment - just the normal run to run ebb and flow.

Also GFS is BS from 192. (not just because it is FI but the way it develops a bowling ball secondary trough to pump up Euro heights.

You didn't think it was just going to go all according to plan did you? Let's hope it just a wobble from the UKMO and nothing more. For most on here a proper cold spell is needed to finally get that long awaited snow. Please ECM restore the faith!

[bluearmy]

Gem on a similar page to ec 00z and gfs 12z

the clusters on the eps 00z say that the 12z op could go in a few directions in the transition period  -  

[Mucka]

Even by 144 a lot of variance within GFS ensembles.

Everything from this

to this