bradymk

Quite an interesting 12z GEFS suite Nick. The attached image showing all 20 peterb, control and op at 300hrs, much better than the underwhelming op and previous suites with a lot of members going for quite an amplified atlantic ridge or heights building to N & NE. A lot of options for cold with the control one of the coldest. A bit better news for coldies after what was a poor start to the 12z's.

Yes better polar profile on the UKMO-GM at day 6 compared to GFS. It has Nick Sussex's reindeer shape

More of a ridge in the atlantic though with trough digging deeper in W Europe.

Yes, interestingly, ECM forecast data shows snow late xmas day for birmingham. Its only a very rough guide on "yr.no" site but that was a cold xmas day chart on ECM this evening for sure.

Nice to see the 12z ECM has the development of an arctic high. Nothing too substantial but something like this is what we need to deflect the jet further south to stay north of the PFJ. A much better polar profile than previous runs and GFS.

This run demonstrates the changes we are likely to see run to run. This pattern is likely to result in development of secondary lows and rapid cyclogenesis etc which may have a big effect on future timeframes. That's a nasty low on the GFS 18z

Thanks Ian! I would expect unless MOGREPS supports the UKMO-GM, that it will be modified towards ECM-GFS as it has no model support at the moment (as far as we can see). Interesting though.

If you want something easy on the eyes before you go to sleep tonight, once again, its the CFS daily that offers a pretty stunning january tonight. http://www.meteociel.fr/modeles/cfse_cartes.php?ech=894&code=0&carte=0&mode=2&run=10 GFS 18z showing the possible cold zonal outcome, im sure some in the north and north west wouldn't be too disappointed with that.

ECM continues the zonal outlook, some cold zonality certainly possible towards xmas too but lengthy cold still looking v unlikely but plenty of time to change, either way. Remember the other day, a lot of people were saying, ahh mild charts never downgrade, they never downgrade like cold charts, take a look how the models have sank that euro high in the last few days with the jet now further south with a more unsettled zonal outlook. I know it is still a mild outcome but it shows that the models don't necessarily have a better verification for mild outcomes.

ECM showing a bit more hope than the other models, +192 is not bad

Models have become more interesting again after the very boring weekend of model watching. Hopefully ECM last night has found a new trend, ENS were most interesting they have been for a while last night too, looking forward to what todays 12z run delivers. Hopefully the v cold air in the US can help dive the jet further south

Depends how much of a south easterly, continental flow we can get out of it. GEM has a cold surface flow, max 2-5c for most of England & Wales. Milder far west and NW. Hopefully the ECM has the position of the high so that we can get some inversion cold too, probably the most realistic way we could get cold weather in the next two weeks.

GEM backs down from the bitter easterly but still best of the 12z's, well in terms of surface cold towards end of the run. Think thats what we need to aim for now, continental cold surface feed being realistic. Won't deliver snow but at least it will be more festive

Hopefully more of the models start to follow GEM. brrr incoming

Slightly better troughing in the atlantic, will be pretty much the same as the 6z though. NW-SE split regards to temp next week. Mainly dry for all of the UK.

Poor ECM op but ECM ensemble does not support op. Still a good cluster of colder members longer term. Op clearly way off towards end of run compared to mean. ENS not quite as cold for London but not many mild members there towards the end. Mean around 5c for max temp, 1c min temp by 16th Still waiting for ECM ENS wind chart to update unfortunately but earlier ENS run showed majority of members favoring a SE/E flow. CFS still seeing a v cold period after around 16th December Week 3 chart definitely hinting at a possibly easterly, v cold across the south. This continuing into week 4 but milder weather potentially approaching from west, could be an end to a cold spell or a battleground scenario. Only guides obviously

Yes, quite possible for Pembrokeshire and other western areas for a time. But if the "potential" continental flow does materialise next week, then it would gradually turn a lot colder, especially in the east under dull conditions. ECM had 2c maxes for Central England middle of next week and if that flow holds, it will only get colder albeit mainly overcast and dry.

I know, think you misread my post, was just quoting someone above, no sign of it!! Very true, we could be on the brink of quite a sustained period of cold temperatures not long after this northerly "snap", especially further east you are in the UK. The potential SE/E feed looks like it could stick around for a while and with an inversion and dull overcast days, temperatures could really struggle, especially in the east. If we have a couple of weeks of that followed by westwards movement of the cold pool towards xmas, then December could become a very cold month. The high uppers on the ECM are deceiving

I just died a little inside. Could you explain how you can see this happening? This run has moved towards the Scandi scenario but just does not quite make it in FI thats all, dont see any of this "zonal onslaught to wipe out december and jan that you are on about?

Brilliant post BA From the last few days, I think an anticyclonic south easterly/easterly feed is looking the most likely outcome even though GFS is still toying with milder SW. ECM Ens have been pretty solid on this continental feed though. The cold pool will be too far east at this stage however even with quite high uppers, this flow can deliver v low surface temps. ECM 12z det for example. +6 uppers on the 11th but surface temperatures a chilly max of 2c and overcast for B'ham. http://www.yr.no/place/United_Kingdom/England/Birmingham/long.html Hopefully we can get something to help trigger that cold pool west as we move towards xmas period.

Nice step towards a possible easterly scenario. JMA, ECM and GEM all show it this evening. GEM and ECM ens showed good support for this scenario this morning too. Only dissapointment is the UKMO, oh yeah and the Globally Failed System (GFS)

You need precipitation first for any "cold rain", that chart would be dry and cold

The uppers may not look cold, but it would be cold at the surface for most of the UK towards the end of this run. In time, the cold pool would move westwards. Another great run from ECM. You would see the cold pool start to move further westwards if the run went past 240.

ECM 192 is a great chart i think?, carrying on from this morning's run, still think it may be being a bit quick with its evolution but at least its consistent.

Great chart at 168hrs from ECM. Sticking with its scandi high (not surprised), next few charts will be nice viewing!!