bradymk

Very different day 7 from GFS 18z to 12z. The trough disrupting over the UK and heights much lower over France and Germany in particular. Some snow to even Southern areas next Thursday. Models probably struggling with handling the energy up against the block. If we see more energy going south east than has been modelled though, 18z very plausible as Nick says. Also, completely seperate point but it was a colder ECM run tonight too than it probably looked, with some snow next Thursday on the ECM for some central areas of UK too.

Could be quite chilly next week and the run up to Xmas if we can get that high north enough. Cold, dry and frosty in any cloud breaks. Better than the 13/14c mush the last few days but still not what we all crave unfortunately. Parallel even chillier. UKMO just rubbish Much more seasonal!

The longer range looks not as good on GFS as a few previous runs with the Atlantic ridge and low heights in Europe not showing in FI. But it looks better in the mid term. Still a chance of an easterly for me at around day 8. Quite a few GEFS members agree...

ECM EPS and GEFS at +360.... Both v similar hemispherically but differ in our locale with the above average heights located further to the north west of U.K (Iceland basically) on GEFS compared to further SE and more directly over or to the east of the UK on EPS. JMA probably best output of evening as Nick explains above.

Fed up of commenting on the longer range outputs when the models can't even agree and keep flipping at Day 4/5. But anyway, forgetting what rubbish it's churned up before FI, the third GFS in a row showing heights to our west/north west towards the end... Crumbs I know but not much else to talk about today.

GEFS mean at +384 looking very similar to CFS weekly for similar timeframe....

Perhaps like JMA 12z from last night, showed a High re-establishing itself over north west Europe again around Day 10.

No consistency at all in the longer ranges of the models which is making it quite a challenge as to what happens after the warm up next week. Still a lot of uncertainty in the Pacific and there are changes of the intensity of the aleutian high every run from GFS. This afternoon run shows a much more intense ridge than 00z run. It's not going to change the outcome next week I know but a stronger poleward ridge may help us further down the line and affects the positioning and intensity of any arctic high Big differences between UKMO and GFS in America too at Day 6 and 7. Coldies like us on the east coast won't want the UKMO to verify over GFS here that's for sure. Pretty grim viewing for U.K next week though, but probably just had the coldest week here since Nov 2010 for the time of year. Now let's hope the EC and GFS ens start to pick up on a more blocked trend in the extended period. I probably sound a bit optimistic but there's a lot more to be optimistic about than the last few years...

Could be about to enter a period of quite prolonged below average temperatures at the surface anyway. ECM temperatures from tonight's run looking below average for all for the next week. An example is for the London area, ECM going for maximum of only 1/2c Tuesday, and possible lows of -6/-7c tuesday night. A very cold night for some, -9c Tuesday night in some spots!!

Very good 144 chart from ECM. Negatively tilted trough, it models the energy so much better.

Wow the mid range is so uncertain. ECM run is basically what John Hammond said last night that there was still a risk that the high would be further west. Was not expecting that run though...

Looks like ecmwf seeing an easterly flow weeks 3 and getting stronger week 4 then judging by those temperature charts. Haven't seen any 500hpa anomaly charts yet. Shame it's still 3 weeks away but like I said last night, would still rather it be showing the cold outcome it is rather than mild anomalies regardless of how unreliable it's been or how far away it is.

While we wait for some more news on the weeklies, Here are today's updated JMA long range ensembles, still looking good... week 2 Week 3&4 The 12z JMA op too....we can dream

BA was talking earlier about the building aleutians ridge in the ENS, and how this could be one of the things that is causing so much uncertainty in the models. This EC ENS graph really shows the big change over the aleutians in the next two weeks or so! Pretty strong negative anomaly back at start/mid of november to a strong positive anomaly by first week December. Big changes in the Pacific next week.

Yes Nick agree, but either way its still a well respected model and the EC weeklies are probably one of the most used model for longer range forecasting. But yes its performance still isn't perfect but lets be honest, which model is at the moment? Just another model that we can add to the discussion i suppose. Either way, it was last weeks run!!

haha yep noticed as soon as i posted! sorry guys, got a bit excited too quickly delete mods!

Some ECM weekly updates, still looking very good mid December... Never mind that's last weeks haha!

One thing the models do agree on is a large poleward ridge developing in the North Pacific. Showing well on the EPS and GEFS. Below is tonight's 240 EC Op anomaly, pretty prominent feature building in the Pacific. Someone correct me if I'm wrong, but a North Pacific poleward ridge a potential teleconnector to a GH ridge down the line?

Big difference between yesterday's +216 (bottom) and today's +192 (top) and a big improvement. That trough to the west of us digging very far south. Still disagreements earlier on between GFS and ECM regarding Greenland and the GFS northerly but at least ECM is looking much better than before, even if the GFS northerly next week does turn out to be incorrect. High pressure in charge with definite potential for heights to then continue building further north and east of the UK as we go further on...

Models still struggling with the position of the lows for the next few days. Mondays low much further south on 12z. A dry chilly day for many on this run.

Not got any full ECM access, but this graph is the ECM data for the Birmingham area for the weekend. No snow but very cold Sunday, with temperatures not rising above 2/3c Sunday daytime. Probably a greater risk than snow is the potential for ice/some freezing rain at first in some locations.

Second LP crossing southern U.K. on Monday on this run is much further south. More heavy rain, and potentially snow for some from this. Saturday night/Sunday starting to look quite stormy now too.

This sort of pattern sure has been a rare occurrence for the past few years! The usual late November Atlantic train absolutely nowhere to be seen.

Last few ECM charts just trickling out. Although each run is slightly different atm, what both GFS and ECM do clearly show is as we move after mid month, heights rise to our north west, the flow becoming much more meridional and what looks a very weak vortex. Some eye candy FI runs will soon be appearing I think.... Paris had its first snow this morning and some low land northern and eastern U.K. could see there's next few days...a good start

Looks like the difference in Height anomalies for the 12z ECM ENS compared to the 00z ENS run. So basically ECM 12z ENS showing large difference in height anomalies particularly in mid Atlantic and to our north east compared to 00z in the mid range. I guess with the weeklies, he means to sort of disregard the weeklies tonight because his following tweet says these are initialised using 00z ECM data and due to the big change in the ENS tonight, they may be more inaccurate. Hope that helps