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

[The PIT]

12 oz out no sign off any cold as the Atlantic rules the roost. Stormy weekend coming up though with some damaging gusts around. Should be some trees uprooted and large branches down to make the returning xmas journey interesting. Bye Bye wheelie bins on Saturday I think.

[Barmada Casten]

Reference flights, British Airways operating a 70% schedule today.

flights definetely on today, seen 14 passenger jets, 3 cargo carriers, and 4 privates today. Seems to have recended in the last couple of hours but expect more later.

Ocean activity at roughly 70% as well, commercial shipping nu,bers functioning at 90%.

[Summer Sun]

GFS has remained consistent now for 3 days about rising pressure as 2013 arrives and its the same tonight

It could be a happy new year for the flood hit regions of the UK at the end of the run high pressure builds to the east of the UK

Edited December 25, 2012 by Gavin.

[Summer Sun]

Looking at the Anomaly charts tonight and they also remain consistent with high pressure building and blocking off the Atlantic giving us a welcome break from the Atlantic rain

If your fed up of this endless rain keep your fingers crossed as next week could see some of the best weather we've had in a long long time, maybe not wall to wall sun but it will be dry which is the important thing!

[A Winter's Tale]

Good evening and I hope you are all having a Very Merry Christmas. Overnight into Boxing Day a line of organised showers will make its way south across Scotland with snow falling above 300-400m but this feature should bring a spell of patchy light rain and cloud cover to Northern England later in the night. There should be some showers scattered around the British Isles - particulary near the coast. However there should be some clear skies overnight in some places such as parts of Ireland, Wales and southern/central England. A cool night with lows of 3 to 8C.

For the morning - it's a largely dry affair with some remaining showers however a band of rain should be moving in from the south west into Ireland. There should be a mixture of clear, partly cloudy and temporarily overcast skies spread out across the British Isles but south eastern areas look best for some morning sunshine.

For the afternoon it seems that this area of heavy rain will be located across Northern Ireland all the way to south eastern England with some heavy showers along the Channel - the south west and central England, Ireland and Wales are likely to see some rain as the feature pushed north eastwards. Drier further north with some clear intervals. Maximum temperatures ranging from 2C in a chilly northern Scotland to 11C in south coast of England under the milder flow.

For the night-time period this band of rain will continue to push further north with northern England, Northern Ireland and southern Scotland experiencing overnight rainfall. Ahead of the front and it's cold with an air frost in the northern Higlands and and the northern isles. Milder behind the front with some clear spells in places and maybe some showers near the coast. Lows of -2 to 8C.

For Thursday there could still be rain located across southern Scotland and Northern Ireland whilst another area of rain moving in from the west may affect parts of Ireland, Wales and England for a time but once this clears there could be sunshine and showers. A cold day in the north with some low maximum values in higland Scotland - possibly just above freezing in one or two spots - whilst in Cornwall it should be much milder with highs close to 10C.

There could still be some light rain lingering into the night across parts of Scotland as another system pushes in from the west bringing a spell of rain to Ireland and the south west. Cold temperatures ahead of the front, overnight lows ranging from -2C in Shetland to 8C close to the sea in the south west.

Friday is not looking all that inspiring at the moment with what seems to be overcast skies everywhere with widespread light rain and some heavy rain in western areas. A much milder day - possibly maxima still in single figures in the very north of Scotland - but generally highs should be 9 to 12C for most under a mild and quite a strong south westerly flow.

And Friday night for now doesn't look anymore promising with a prolonged period of persistent and heavy rainfall for western areas in particulary whilst some eastern areas could be somewhat drier but clear night skies will be very hard to come by. Overnight lows of 4 to 10C.

Saturday is looking different however: the band of rain that affected many areas overnight should be over the south east, however, a cooler westerly flow develops feeding plentiful showers into some western coasts with sunny spells for many. A cooler day in Scotland and Ireland but possibly still mild across large parts of England and Wales - highs of 6 to 11C.

Saturday night certainly colder than of late with lows of 1 to 5C. However the fresh and cool westerly flow should feed plentiful showers into western areas and these showers should also make their way further inland.

Sunday could be a similar day with a cool westerly flow feeding in more showers and these showers could be wintry in Scotland - particulary on the high ground.

However for Monday, with the aid of high pressure to the south of the British Isles, southwesterly winds makes enrodes bringing potentially another period of persistent, widespread and heavy rainfall and also milder temperatures.

Then for Tuesday, with low pressure to the north east and an area of high pressure attempting to ridge northwards - a cold, wintry northwesterly flow develops.

As the high itself makes enrodes from the west, the cold airflow is pushed further east - bringing more settled conditions to southern areas in particular and possibly some low temperatures for Scotland with cold air still present.

Thereafter and you can only guess what the weather will be like but we can get a general grasp of things by looking at trends. Logically, with the sort of chart such as the one below, you'd expect milder air to roll ontop of the high.

As I mentioned a few days ago to keep an eye on the northward movement of high pressure to our south. This could bring a period of settled and drier weather although north western areas are far from immune from frontal systems. The trend is indeed - for now, atleast - for high pressure to push northward but it's positioning will have implications for our weather: if it ends up further east then we could be under a southerly flow and at risk of fronts grinding to a halt over the British Isles with renewed concerns of further flooding. Potentially, the high could end up right ontop of the British Isles with more settled and drier conditions for most. But all of this is speculation and it's importnat to remember that this movement of the high may not happen at all. That's the art of observing the evolution of synoptic trends in the models. And this particular movement of high pressure is one facet of all the factors that contribute to the weather so all in all there's a lot to look out for. Enjoy the rest of today everyone!

[Weathizard]

Nothing is looking good for cold within 15 days on recent runs but at least we are seeing our normal foe of the Iberian high saving us from MORE rain, to be honest I'm actually quite happy to see that in the charts for once! Let's be honest we need the warming to ride in to our rescue because that Vortex positioning at 240 on the ECM is absolutely terrible for cold prospects.

[Jason M]

According to ECM we are due a major warming episode at 10 days...

http://www.meteociel.fr/modeles/ecmwf.php?ech=240&mode=0&map=0&archive=0

In fairness the 12Z GFS ensembles are a bit more positive around the 192 hours mark. they mostly default to a flat pattern or a mid atlantic high in the form of the dreaded 'blob' with the jet riding over the top. To be fair though that that tends to happen in low res anyway as GFS tends to revert to type once it hits low res.

Interesting to see if the expected pattern change begins to show itself soon although much as I respect others views i'm a little sceptical that there will be an easy way out of this pattern. Everything screamed Bartlett yesterday and although I think the models have backed away from that today a little bit, its still a possibility.

Jason

[Summer Sun]

Good evening

ECM continues to follow GFS by rising pressure from mid next week giving most areas away from Scotland a respite from the rain

Again as with GFS the ECM Anomaly supports this idea

[EML Network]

Well sadly the GFS and ECM don't offer us anything in the way of an XMas present, quite the opposite in fact.

Both models suggesting High pressure to make it's presence felt as we go into January and Temperatures likely to be very mild in the South during the day time, and mild across most other parts by day.

At least those hit by the flooding might get a respite.

I still can't see anything that is going to deliver us anything more than temporary North Westerly's, there really is only one way to go now, the charts in FI can't get any worse from a cold lovers perspective , so as much as it pains me to say on XMas day....as far as cold and snow potential goes, we're at rock bottom.

Edited December 25, 2012 by EML Network

[TEITS]

Hope everyone has had a good Christmas.

The models are awful as usual and to be honest I didn't expect much change. The most disappointing though is the sheer lack of cold runs in the ensembles even in distant F.I.

http://cdn.nwstatic.co.uk/ensimages/ens.20121225/12/t850Cambridgeshire.png

Still yet to be convinced of this so called pattern change.Very unusual for the ensembles to be so poor in F.I because normally at least a few runs give you hope. Obviously there is a very strong signal for a positive NAO.

[PubliusEnigma]

Merry Christmas to you all. Lets hope by the end of January, the month will end up, different to how it it starts.

A quick look at the latest ECM offering which shows the worst of the rain edging northwards into NW Scotland,

as High Pressure from a displaced Iberian High heads closer to the UK, over Biscay. All thing being equal, the worst

of the rain should move north into Scotland with a drier respite along the south and SW where it will be needed.

Staying mild though, but possibly Foggy at times later in the far south..

[Gibby]

Good evening. Hope you all have had a good day and here is the report on the 12zs from the big three tonight.

All models continue with the pattern as before in the period up to the New Year. The current showery flow will last overnight with some heavy showers in the West. Through Boxing Day a band of cloud and rain will sweep East over the UK before clearing again later. Winds will blow from the SW or West across the UK in temperatures close to normal. Thursday sees a mix of sunshine and showers in a fresh West wind with some wintry showers over Northern hills. On Friday and Saturday a couple of extremely windy days seems likely due to a very deep depression out to the NW of Britain pushing gale SW winds over the UK along with some very wet weather for all at some point. By the end of Saturday a squally cold front brings colder and more showery conditions back over the Uk with further wintry showers over Northern hills again. Towards New Year a further band of rain moves across the UK on further strong SW winds with New Years Day currently looking rather windy and showery as a cold front clears East.

GFS then shows High pressure building from the South as we move further into 2013 with drier and more settled weather in the South with less rain for the North too. Late in FI the High drifts a little towards the East still bearing influence on the weather for the East while the West see Southerly winds freshen with some rain.

The GFS Ensembles data shows a continuing unsettled pattern for the next week or so before High pressure to the South looks like trending things mild and rather less wet as we move into the second week.

The Jet Stream continues to undulate across the Atlantic to the UK unrelenting for the coming week or so.

UKMO for midday on Monday shows Low pressure to the North of Scotland with a broad SW flow over the UK with a trough out to the West approaching the West of the UK with rain later in the day.

ECM tonight shows an unsettled end to the year and start to the New Year with further rain and showers before High pressure builds from the South later next week though with the High in the position shown ther would be a lot of cloud moving round the High off the atlantic with weak fronts embedded bringing drizzly rain in places. It will generally be mild as we move into the New Year too.

In Summary there is another week of unsettled and rather windy weather with some heavy rain on occasion for all and some wintry showers on hills in the North in the brief showery spells. It then looks like becoming rather drier though still mild later next week as High pressure is shown to build from the South.

Edited December 25, 2012 by Gibby

[snowmackem]

Well that latest GFS run has cheered me up and probably most cold fans in the UK as well as a rest bite from the Rinse Hold synoptics for most of December in your longitude. Especially good charts for the Eastern Alps and the start of the main ski-ing season. This run looks more feasible than the previous cold block forecast for Western Europe. Lets hope this now becomes the latest trend for January .

C

respite?

[PubliusEnigma]

Hope everyone has had a good Christmas.

The models are awful as usual and to be honest I didn't expect much change. The most disappointing though is the sheer lack of cold runs in the ensembles even in distant F.I.

http://cdn.nwstatic....bridgeshire.png

Still yet to be convinced of this so called pattern change.Very unusual for the ensembles to be so poor in F.I because normally at least a few runs give you hope. Obviously there is a very strong signal for a positive NAO.

Agreed, GFS has been the form horse this winter to spot something changing first out in FI. Not sure I would go with any suggestion of a pattern change ?

What I find most annoying of all, as we are now in mid winter, we will see later in the runs, High Pressure where we long for it in Summer instead of the

Greeny High we have all summer that disappears in mid winter.. Oh well, maybe better luck next year, with some snow before winters' out and something drier in the summer. Will be interesting to see where the Anticyclone progged just to our south at T240 heads in the week beyond. Will it go NE into Scandi, become are bartlett, or drift south back towards Spain..?

[Summer Sun]

Agreed, GFS has been the form horse this winter to spot something changing first out in FI. Not sure I would go with any suggestion of a pattern change ?

What I find most annoying of all, as we are now in mid winter, we will see later in the runs, High Pressure where we long for it in Summer instead of the

Greeny High we have all summer that disappears in mid winter.. Oh well, maybe better luck next year, with some snow before winters' out and something drier in the summer. Will be interesting to see where the Anticyclone progged just to our south at T240 heads in the week beyond. Will it go NE into Scandi, become are bartlett, or drift south back towards Spain..?

Yes its amazing GFS picked up on this pressure rise for next week 3 days ago now and since then its kept that idea and now ECM is on board, yet come summer all the high pressure stays in FI an never gets support

[Duane S.]

Hope everyone has had a good Christmas.

The models are awful as usual and to be honest I didn't expect much change. The most disappointing though is the sheer lack of cold runs in the ensembles even in distant F.I.

http://cdn.nwstatic....bridgeshire.png

Still yet to be convinced of this so called pattern change.Very unusual for the ensembles to be so poor in F.I because normally at least a few runs give you hope. Obviously there is a very strong signal for a positive NAO.

I agree that this is the most disappointing aspect right now. I'm happy to see the Ops spew their mild mush every 6 / 12 hours whilst an underlying cold trend in the ens was building but despite some tentative signs, the ensembles are having none of it either. That said we've all seen ens suite switch lock and stock overnight before so with the (albeit, high up) warming due to hit in a few days time, a relatively quick switch to cold modeled on the charts can't be ruled out as a possibility.

[Snowman.]

The GFS has been hinting at pressure rises from the south the past couple of days. The other models are following suite. A scandi high and low pressure in Atlantic with trough into the MEd. in FI could be a new trend. In fact it ties in with the Netweather winter forecast for January.

How many times has it done that this winter?

I'm a coldie yes but what I'm looking for is less energy in Canada and Higher pressure near Greenland that wont last long at would be dry as well.

Still hopping for a PV over the Russian side of the pole giving Pressure rises in Greenland with ridging into the Atlantic.

[Ian Brown]

Hope everyone has had a good Christmas.

The models are awful as usual and to be honest I didn't expect much change. The most disappointing though is the sheer lack of cold runs in the ensembles even in distant F.I.

http://cdn.nwstatic....bridgeshire.png

Still yet to be convinced of this so called pattern change.Very unusual for the ensembles to be so poor in F.I because normally at least a few runs give you hope. Obviously there is a very strong signal for a positive NAO.

Yes, the positive tonight is that at least if the Azores High can get as far North as shown then it will give relieve from the constant rainfall for the Southern half of the country at least, although with such low heights to the North it would only topple back South eventually.

[Ian Brown]

Well sadly the GFS and ECM don't offer us anything in the way of an XMas present, quite the opposite in fact.

Both models suggesting High pressure to make it's presence felt as we go into January and Temperatures likely to be very mild in the South during the day time, and mild across most other parts by day.

At least those hit by the flooding might get a respite.

I still can't see anything that is going to deliver us anything more than temporary North Westerly's, there really is only one way to go now, the charts in FI can't get any worse from a cold lovers perspective , so as much as it pains me to say on XMas day....as far as cold and snow potential goes, we're at rock bottom.

Yes, it is the worst possible position for cold going forward, though if we were back in the mid-80s would we worry about these charts with Jan and Feb still to come ?

[Geordiesnow]

Still keeping an eye on that slight cold shot for Thursday, still the potential for snowfall across Southern Scotland I feel, especially on higher ground, its a long shot but with timing etc, it may be the best chance we could have for a while!

Still, looking forward to a bit of strong winds and rain, can't be cold all the time!

[Dave Kightley]

Pressure building from the south. Can't see why it won't eventually move West or North with all the Warming's up North early next month. I will be expecting things to get interesting in the next few weeks Happy Christmas to you all

[I remember Atlantic 252]

Yes, it is the worst possible position for cold going forward, though if we were back in the mid-80s would we worry about these charts with Jan and Feb still to come ?

No we wouldnt, could guarantee snow in Jan and Feb and March back then, cant guarantee it now, but models are starting to look better, not for snow, but for inversion cold, still in FI, high may centre over us, after new years day mini toppler, then very chilly

[Snowman.]

How many times has it done that this winter?

I'm a coldie yes but what I'm looking for is less energy in Canada and Higher pressure near Greenland that wont last long at would be dry as well.

Still hopping for a PV over the Russian side of the pole giving Pressure rises in Greenland with ridging into the Atlantic.

Too add with everything that is meant to happen, models are going to have a hard time with the warming strat so FI is really unrealistic.

[The PIT]

Sadly all the pressure rise does is give us mild rubbish in the ecm and the nail in the coffin dreaded euro high in the gfs also mild prolonged rubbish.

[snowmadchrisuk]

Well I think we need the pressure rise to get out of the pattern that we are currently in ... What is to say the pressure won't rise far enough to bring in an Easterly , Or to retrogress and setup a Cold pattern ... Something has to happen and at this time of year , quite often pressure building over the UK , results in an eventual cold Spell, Bartlet very unlikely in my opinion as that usually happens when pressure rises from the SE and that doesn't look to be the case with this high .