Winter Model Discussion - Cold Hunting -23/12/12

[Froze were the Days]

CFS v2 model also predicts mid-latitude blocking and possibly to our north around the beginning of the New Year and again with a significant Greenland HP around mid-month, have been following this model from the end of November and has to be said by and large so far for December has been quite accurate other than to get the zonal conditions in maybe a week too early. So maybe a straw to clutch to.

Edited December 23, 2012 by Froze were the Days

[legritter]

Evening all ,plenty of weather still generated thanks to our friend the atlantic and our friend to our north ,between them sending their goods of creation in our direction . this coming week more of the same .but signs now showing of high pressure perhaps getting in on the act next weekend .beyond that it could in my opinion go many ways .So the hunt for cold goes on ,if there are posters out there who think we are running out of time [DONT] plenty plenty of time left for colder shots . having studied past winters going back hundreds of years there are many that turn up in winters that start Zonal and wet . i have spent recent days watching events in canada /north america their modells are hinting at changes which could feed into our side of the big pond . J

[bobbydog]

well, just looked through the various models on metiocel on a straw clutching mission and i can't find anything hopeful. the only thing left (forecast-wise) is the strat warming. even then, chiono is not confident it will be enough. i had a good feeling about that but one post from him has peed on my fireworks a little. the only positive things i can find are that there is still a lot of uncertainty and even the Meto are hinting at possible colder weather in mid january. the other thing is that looking through the archives, the current weather patterns are not a million miles away from december 1990.... (remember feb 1991?)

anyway, if carsberg did model runs..... well they don't- but they do make beer and at least i know my fridge will be cold, even if the weather isn't.....

[legritter]

Sorry cocked up on last post ,Happy Christmas to all posters and have a good day tuesday ,cheers legritter .

[bluearmy]

well, just looked through the various models on metiocel on a straw clutching mission and i can't find anything hopeful. the only thing left (forecast-wise) is the strat warming. even then, chiono is not confident it will be enough. i had a good feeling about that but one post from him has peed on my fireworks a little. the only positive things i can find are that there is still a lot of uncertainty and even the Meto are hinting at possible colder weather in mid january. the other thing is that looking through the archives, the current weather patterns are not a million miles away from december 1990.... (remember feb 1991?)

anyway, if carsberg did model runs..... well they don't- but they do make beer and at least i know my fridge will be cold, even if the weather isn't.....

Ed is simply stating that we may not achieve a technical SSW. There will be a strong warming that will displace/split apart the vortex. Whatever reforms will be much weaker than we currently have and there will be greater opportunities for HLB thereafter (no idea how long). A technical SSW is nearly always better than a strong warming re results but not imperative.

[damianslaw]

Perhaps we should rename this thread the hunt for dry weather..

For the foreseeable future all the models are keen on maintaining a very flat atlantic zonal pattern which will mean mostly mild wet windy conditions through the next few days - a very uninspiring outlook for many and certainly not good news for places prone to flood risk - indeed its the worst possible outlook in this respect.

ECM showing a scenario which those wanting some dry weather will be hoping happens as we move into the New Year i.e. amplification in the atlantic flow allowing heights to rise in the mid atlantic which may enable a lengthier drier period to bed in if we see heights also building to the north blocking the atlantic. Its a long way off but it will be interesting to see whether on my return to model viewing on the 27th such a development is still showing - fingers crossed because I don't think any of us want to see sustained very wet weather.

What has been remarkable about the weather since the late May dry spell is how little we have been influenced by high pressure, indeed when was the last time we saw high pressure settled over or close to the country for any length of time - I can't remember. 2012 has been the year of the troublesome trough, hoping for a change in 2013, otherwise flooding will become a major major issue for many in the weeks to come... the weather does have a habit of going from one extreme to the other, and just like how in April the taps were turned on after a long period of drought, who knows we may see a sudden abrupt change after the 8 very wet months we have endured since then..

[bobbydog]

Ed is simply stating that we may not achieve a technical SSW. There will be a strong warming that will displace/split apart the vortex. Whatever reforms will be much weaker than we currently have and there will be greater opportunities for HLB thereafter (no idea how long). A technical SSW is nearly always better than a strong warming re results but not imperative.

i realise that but with the current output it would have been nice to see something definitive to affect our weather. it may do so yet but it still doesn't instill confidence towards major changes. however it is interesting to watch and see how things turn out

[-uksnow-]

Good to see the 18z is heading more in the direction of the 12z ECM ..

18z GFS @168

12z ECM @168

[Panayiotis]

Very cold NW wind on the 18z at 162hrs, also showed this on the 12z, 06z,00z and the 18z(yesterday) however each run until now has upgraded it. But this was the case, when showing the cold weather for the 26th a couple of days ago and now look what the models are showing for that date (not cold at all!)

Snowfest for Scotland at 168hrs!

Edited December 23, 2012 by Panayiotis

[Backtrack]

Some colder prospects on offer at the end of the 7 day period, here's my take on things:

Monday 24th

Christmas Eve certainly isn’t going to feel very festive at all. There looks like being a band of heavy persistent rain sat over most of the UK for the duration of the day, gradually edging eastwards as the day progresses. Some eastern and south eastern areas will escape most of the rain until the early evening, but even here it will be impossible to avoid a soaking. The temperatures don’t look very festive either, double figures in the south east, elsewhere in England & Wales 5-6C will be the typical max. Colder in northern Scotland.

Tuesday 25th

As the title suggests, it’s not going to be a white Christmas this year unfortunately. We’re locked into an Atlantic dominated pattern at the minute, and that is certainly not going to shift in time for the big day. It’s going to start off cloudy with outbreaks of rain in the south and west of the country, and these showers will spread NE during the day although as the afternoon wears on, they will tend to become more hit and miss. A predominantly cloudy day in all areas with very limited brightness although it may brighten up from the west for a time in the late afternoon.

Wednesday 26th

Boxing Day looks like starting off fine and bright in many areas, perhaps even a touch of grass frost in rural areas, but it will soon cloud over from the west as yet another Atlantic front makes it’s way in from the west bringing the threat of more heavy rain into the evening although this one should be fairly quick to move through and should not cause much disruption. Away from that, a mainly cloudy day yet again with temperatures of 5-7C.

Thursday 27th

A better day on Thursday with much more sunshine on offer as of late as a more showers regime takes over with most of the showers around in northern and western areas, although even here they will be few and far between. Temperatures holding up at around the 6-7C mark widely, the winds will be gusty though, even inland taking the edge off the temperatures, making it feel cool, even in the sunshine.

Friday 28th

Temperatures recovering to well above average values on Friday, as high as 12C. More rain too, limited this time to northern and western areas though with the south escaping the worst of the wet weather. The winds will be picking up from the south west too, a mild direction for weather at any time of year, so it shouldn’t feel too cool, even in the rain. Where the rain does not effect, it’ll be another cloudy day due to the influence of low pressure.

Saturday 29th

After a very mild night (temperatures perhaps not even falling below 9-10C) the temperatures will of remained pretty much constant throughout the 24 hour period, maxing out yet again at 8-11C widely with the exception of northern Scotland as you would expect at this time of year. A dry, cloudy morning in the west will be intercepted by more wet weather from the Atlantic, the rain is now becoming a serious problem, flooding is an issue. Winds still pretty gusty in many areas too, especially, but not exclusively on the coasts.

Sunday 30th

Winds will have switched to a northerly quadrant on Sunday meaning colder air is likely to filter down from the north. This is likely to be a very temporary event as the remorseless Atlantic regains control after a brief 12-24 hour of colder, more seasonal weather. Temperatures falling throughout the afternoon, although generally around 5-6C with any wetter weather clearing gradually.

[nick sussex]

It looks like that eastern USA troughing will play a key role. The GFS lower resolution flattens the pattern out and sends the energy eastwards.

The ECM sent the energy ne'wards as it held onto more amplification. I can't really see any route to cold within 10 days that doesn't involve that eastern troughing doing us a favour.

Aswell as this it must not phase with the low to the west of the UK. Overall its like pulling teeth to get cold into the UK at the moment.I will be interested to see what NOAA say tomorrow because their discussions on Friday re a neg NAO,AO and positive PNA should be delivering something upstream and not these crumbs!

Either they're badly wrong or the operational output is!

[Panayiotis]

Today we have seen improvements on every run in the shorter term, to me the 18z had defaulted to the zonal in Fi and over this winter, I have seen that the projection in Fi is completely different to the outcome.

[bluearmy]

The 18z really does ramp up those low thicknesses just north of scotland in the latter part of high res. i will assume for the time being that this is the furthest point the pendulum can swing. If there was any more correction, would get a tad interesting for new year.

[nick sussex]

The 18z really does ramp up those low thicknesses just north of scotland in the latter part of high res. i will assume for the time being that this is the furthest point the pendulum can swing. If there was any more correction, would get a tad interesting for new year.

Won't the models do what they've just done. Take the jet further north and what looks interesting at one point turns into a damp squib nearer the time.

Personally I'm hanging my hat on that eastern USA troughing, either that does us a favour or its going to be a longer wait for anything resembling winter.

[Fozfoster]

Well guys just finished 21 days on the spin AT WORK and tryed to keep up !! But would just like to say thanks to all you guys and girls on your modelling analysis , loved it THANK YOU.

Merry Christmas.

[Tim Bland]

Surely the only model that has the new year pattern nailed is BOM ... We wish lol

http://www.meteociel.fr/modeles/bome_cartes.php?ech=240&code=0&mode=0&carte=1&archive=0

[mulzy]

Surely the only model that has the new year pattern nailed is BOM ... We wish lol

http://www.meteociel...rte=1&archive=0

A weak Northerly toppler - great!

Truly dreadful models and ensembles today (if you're a coldie!)- guess this is the low point of the winter - things can only get better folks!

Edited December 24, 2012 by mulzy

[swfc]

Does anyone know if there are threads available from the winter and severe cold ete from 2010 on here?the mo at moment is that bad id love to read threw them posts during the build up and actuall cold spell just to cheer myself up!!!!

[Robbie Garrett]

Hopefully the CFS has some delay onto it...

[Panayiotis]

Hmm getting more interesting now on the 00z at 144hrs, folks in Scotland and Ireland should be happy with this and hopefully it will come to us down south!

Edited December 24, 2012 by Panayiotis

[Panayiotis]

Nicer charts now showing for New year, if you look the 18z and the 00z go for similar options (bringing in the cold NW) however taking different initial routes, personally I prefer the 00z as the low to the north is very deep and its acting more like a clog bringing those cold uppers towards us! Bring 100-200miles south, and we'll be in the freezer.

Edited December 24, 2012 by Panayiotis

[Zakos]

Very impressive change in temperatures over 24 hours.

One advantage of this very mobile setup is that any attempt of a Bartlett-type setup to develop will fail, as the block will get blasted away by the jet stream.Conditions look very changeable, and the outlook is not snowless, especially in the North west.

Unfortunately there does not seem to be much respite from the rain deluge. I am personally getting sick and tired of low pressure in the Atlantic. Mostly because it is wrecking havoc in western areas by causing flooding.

We've seen significant HP over Scandinavia and Russia, and now we have strong HP over Canada and the Arctic, but still the Atlantic refuses to calm down. Let us hope the experts are right and we will see colder and drier conditions later in janurary.

Edited December 24, 2012 by Zakos

[Panayiotis]

The 00z has been a good run,best ive seen in a couple of days now. Fi but lovely looking chart. One thing though that HP which is in the Atlantic starts off as a weak low can someone explain, never seen it happen before!?

At 384hrs.

At 324hrs.

Edited December 24, 2012 by Panayiotis

[swfc]

Nicer charts now showing for New year, if you look the 18z and the 00z go for similar options (bringing in the cold NW) however taking different initial routes, personally I prefer the 00z as the low to the north is very deep and its acting more like a clog bringing those cold uppers towards us! Bring 100-200miles south, and we'll be in the freezer.

In the reliable time frames this run is diabolical to be honest.The uk stands zero chance of being in the freezer and even more worrying is the rise in pressure over southern and central europe!!!!The flooded parts of the uk will benefit from this set up which is great.Also forget fi way out its just another straw to clutch and will be gone later today.Just to note there is a short spell of decent 850s between 150 hours tll 180 hrs.After that its gone.All in fi still also Edited December 24, 2012 by swfc

[Panayiotis]

In the reliable time frames this run is diabolical to be honest.The uk stands zero chance of being in the freezer and even more worrying is the rise in pressure over southern and central europe!!!!The flooded parts of the uk will benefit from this set up which is great.Also forget fi way out its just another straw to clutch and will be gone later today

You dont know this, so dont put too much confidence into it! Today we have seen some major improvements up to 72hrs and beyond, im not saying we will, just saying if the low moved south we could go into the freezer (temporarily). As stated by Zakos, I dont think the pressure rise over Europe isnt a major problem yet as the jet is south of Britain. Edited December 24, 2012 by Panayiotis