comet

Glad to see normal service has resumed with the model output returning to the pattern it was showing before it went awol on Saturdays 18z run and Sundays runs. Would be interesting to know exactly what caused the models to flip like they did. Anyway things look back on track and an east or north easterly airflow looks almost to be a dead cert ( if there is such a thing with the weather ) by months end into February as I have mentioned a few times lately. Have to say though good call from MR Murr yesterday when he (many posters myself included thought we had been led up the garden path yet again), refused to believe the implosion seen by the synoptics on display. All to play for again now with confidence very high of potent cold spell just around the corner.

Very disappointing model viewing it has to be said. It certainly makes you feel that this model watching is a complete waste of time, commentating on charts at plus t168 then everything implodes and charts at t96 etc can not be trusted. Not trying to have a dig but even positive posts from those that follow the teleconnects more closely look to have come unstuck. I have never been a fan of the NOAA updates as they never seem to offer much assistance and sure enough the last update I read on here mentioned a more amplified upstream pattern over the states which would have benefited us yet the reverse now seems to be the case. Warming is still being advertised in the gfs strat charts but this has been somewhat delayed and watered down from what the charts were showing three or 4 days ago although it does look as though there is now more of a response height wise with the vortices becoming more stretched again at 10 and 30mb. If this trend continues then a split may well be evident in early February. Some of the more favoured areas likely to see some snow (perhaps significant) this week while for most the chance of some wintry showers with maybe a temporarily covering.

You definitely get the feeling that something is brewing as we head towards late Jan and on into Feb. Even the ecm t240 chart although going the way of the pear for us has a very promising configuration especially for our side of the pole. Coupled with strat forcing and a favourable MJO signal charts like the gfs 12z op is showing may not be far fetched at all and may well be bettered over the coming days. That is a long way off though and much water to get under the bridge before then especially with what's being modelled for the coming week. My concerns being pehaps not as cold as the gfs would have us believe nor as snowy apart from the more favoured locations.

Judging by the Euro models it looks as though the GFS is a couple of degrees low on the 850 temps and if so will make a big difference to where lowland Britain will see low land snow and accumulation. As far as the gfs FI goes it is just that FI at the present time.

Trouble with the slider, runner call it what you will, is, unless its a very shallow weak low its has the effect of flattening the Atlantic ridge thus turning the flow more westerly than north westerly and subsequently the low takes on a more northerly track. If this has already been mentioned then ignore.

Still no sign as yet of the forecasted warming having much of an impact. The warming at present just seem to be skirting the surf zone. Of course this could soon change, hopefully.

Another rather coldish spell on the way by the looks, with some snow around although not worth going into to much detail at present. Of course further north with elevation it may well be a noteworthy spell of weather to come but certainly no freeze for the majority of us. The forecasted strat warming is now evident in the ecm Berlin charts and forcing from this MAY temporarily shorten any colder synoptic pattern we are in as it changes the dynamics and structure of the atmosphere ( it would not be the first time this has happened) but hopefully we will reap bigger benefits from this as we enter February.

Looks to me as if the strat/trop coupling is as always dictating the pattern ahead, with perhaps conflicting teleconnect signals always playing catch up. Way to early to know how big a player the strat warming is going to be but if things go our way it could lead to the holy grail of weather synoptics if my feelings are anywhere near correct. We may well see the cold pattern relax due to wave 2 forcing waning prior to hopefully very large AO response amplification and proper winter freeze as we go into February. Very interesting times ahead and any strong MJO forcing is likely to inhance AO amplified pattern hopefully.

Regardless of what the Glosea5 model is showing (probably just late to the party) if the strength of warming remains the outcome at this early stage is impossible to forecast. Perhaps in 5 to 10 days we may well see a strong wave 2 response being forecast which could make things very interesting going forward end of Jan into February.

Another very strong warming showing up on the 18z gfs (strongest yet I think). Someone better fix the GloSea 5 lol.

Well can the ukmo go the extra mile. At t144 the chart screams easterly for the UK with energy undercutting as the CAA pushes west from Europe. The only problem being that this is a t144 chart and not the most reliable time frame for the ukmo model. Also although the gfs is slowly realigning towards the ukmo at the time frames we are looking at ( t96-t144 or 4 to six days) you really would expect the gfs to be fully on board. This tells me that because of the disagreement between the models no one model has it right and unfortunately when it comes to cold for the UK there is little room for error. The UK model builds a robust block over northern Scandinavia the gfs not so hence shortwaves aplenty. That aside I am rooting for the UKMO model to be correct because we are just a hairs breath away from what could be a very cold spell of weather if the energy to the west disrupts and goes under the block to the east also the ukmo and the ecm are virtually on the same page out to t144.

True enough but the other two models have not covered themselves in glory either. Even though the 18z goes down a different path what it is showing is the extra amplification in the upcoming pattern which I have been banging on about and which will effectively govern the pattern post t144. Hopefully we will wake to some great charts in the morning.

All sensibility aside for us coldies that are looking for our winter fix and despite perhaps our better judgement, I suppose you could argue whats the point of watching the model output if we ignore even the slightest chance that what the ecm is showing could be right and for that reason I think many will be willing to be sucked in again (including myself). It could after all turn out that this is what the ecm was seeing all along but was being over progressive in developing the pattern first time round. Well that's my straw to clutch.

I love the way the ecm run waits until the block is far enough east before the cold air starts to under cut and head back west. I think we can definitely say the ecm has not lost the ability to over amplify. I have been forecasting the pattern becoming more and more amplified but I must admit not to the extent that the ecm 12z run shows this evening. The worst chart of the day has to be this Can we really fall for it a second time?, and so soon after the last flirtation from the models. It beats looking at zonal dross that's for sure.

Once bitten twice shy. There is obviously disagreement between the ukmo and gfs as early as t96- t120 again with essentially the gfs further east with the pattern and not quite as amplified. A blend of these two models would still leave us in no mans land and fast approaching the middle of Jan. personally I think I am ready to throw the towel in on a possible easterly and instead concentrate on the amplification across the pole that may well lead to a prosperous cold snap/spell from the N/ NE down the line. Must admit beginning to dread easterlies being modelled as they rarely come off but leave us in a state of limbo eating up valuable days or even weeks of winter without bearing any fruit.

I had been thinking the same thing lol. I must admit to not being totally convinced by the UKMO, sure there is definite improvement and amplification from the ecm 12z to this mornings 0z and even on the gfs 06z but it take a leap of faith to go from the ukmo t96 to t120 .

Have very little faith in the models right now and although I fully expect the models to show a lot more amplification in the pattern over the coming days I would certainly not be trusting anything the models show at t168 let alone t240 etc.

At least some good may come out of all this and that being that posters might stop trawling out the lesser models like um GEM perhaps. Although to be fair its been no worse than the ecm. I suppose it also means that the ecm op run has not lost it bias for amplification.

I do not know what happened to the ECM op run this morning but all models (at least the big three) now showing the amplification that I forecast the models would soon start to latch onto due to strat forcing with wave 2 heights building from central northern Europe north. Whether anything meaningful (cold and wintry wise) comes of this amplification remains to be seen but I would expect at the very least 3 or 4 days of cold, very cold weather to come between t144 and t300. Just seen the ecm has gone off on one again. What has happened to that model. Dear oh dear.

We only have to look at the strat charts from Instant weather maps, Berlin etc to see that is happening already. Hence the more amplified northern hemisphere profile with a split up to 30mb.

I think you would have to say judging by the operational output we have in front of us this morning and the runs we have seen in the last few days,the ecm has been woefull. Maybe it's a massive mild outlier.

Just to reiterate its the best performing model hemispherically wise not necessarily for just our neck of the woods. Must admit to being very disappointed at the output this morning. My expectation was very high following the 18z last night and expecting to see much more amplification in the pattern ahead. Note how to weekend cold spell has almost disappeared with the sinking high which I shared my concerns about several times in the last few days. oh well lets see what the 12z bring.

Further runs and adjustments as the models come to realise that there is much more amplification In the pattern ahead. This extra amplification dictating how things evolve. The vortex is forecast to split up to the 30mb level. expect to see further amplification in future runs.

All part of the amplification post t144 that I spoke of in a post earlier today. Strat charts show a split vortex developing right up to the 30mb level out to t 300 ish . I do not think that this is being reflected accurately in the h500 charts and we will see a trend for more amplified runs and a much greater chance of sustaining a potent cold spell for several days. 227

I must admit to being a little more optimistic after seeing the 06z and its ens so I decided to re-visit the ERSL composite strat charts and they to give more confidence of a more amplified pattern developing in the mid range. Further downwelling still instigated by strong wave break in early December over Alaska, northern Canada and now a wave 2 type response from Central, northern Europe extending north should make itself more visible in the troposphere in the next 10 to 15 days so do not be surprised to see the emergence of a more amplified stronger block into northern Scandinavia with much more of a possibility of undercutting. Here's hoping for a much better 12z from the gfs.