Winter Model Discussion - The Hunt For Cold - 12th Dec

[Troubleatmill]

Indeed, yuck about sums it up, as we know things can develop out of seemingly nothing, just as the cold looked locked in and hasnt so can the mild, but the ensembles look like a horror show of mild & wet, with the occasional returning polar maritime air to make the rain colder, s frustrating where the PV is so weak prety much all the way through the run to our North...up the anchor and let us drift a 1000 miles further North

Edited December 13, 2012 by Nick JB

[Frosty.]

The latest GEFS 00z mean also looks poor for any cold prospects with winds generally between southerly and westerly feeding a mix of tropical maritime and rather cooler winds sourced from the north atlantic, no sign of northerlies or easterlies in there, mild winds at times but also a bit cooler with a straight westerly which may be cold enough for a little snow to the scottish mountains. Very unsettled charts with spells of wet and windy weather with low pressure generally to the west of the BI.

[ghrud]

The demise of the PV set to continue and that is a peach of an arctic high.

http://www.meteociel...&mode=0&carte=1

Still very cold outside and has been for a good part of December so far,with snow for the central belt and much of Scotland today.This winter still has the feel of a classic style 7os/80s when the cold comes in as we approach the New year.With plenty of snow cover to our east.Historically we WILL get mider interludes from time to time.

Just thinking of when i could recall such an area of low pressure in the atlantic http://www.meteociel...?&ech=36&mode=0 ,

http://modeles.meteo...8-12-13-0-0.png

Oh,which led to this

http://modeles.meteo...8-12-31-0-0.png

http://modeles.meteo...8-12-31-0-2.png

But, if we had had the computers able to model this scenario in advance in 1978 would they have predicted that outcome? Probably yes! Is there anything resembling this being modelled at the moment? No.... but we can hope.

Edited December 13, 2012 by ghrud

[chiller]

O/T

I don't know why the models are showing predictions after 00z 21.12.12 it's going to be irrelevant

Maybe we should start worrying if anything seriously cold pops up around that date - Doomsday by new iceage! Well we've had the flood so I guess its now fire or ice

[BurwellWeatherWatch]

The demise of the PV set to continue and that is a peach of an arctic high.

http://www.meteociel...&mode=0&carte=1

Still very cold outside and has been for a good part of December so far,with snow for the central belt and much of Scotland today.This winter still has the feel of a classic style 7os/80s when the cold comes in as we approach the New year.With plenty of snow cover to our east.Historically we WILL get mider interludes from time to time.

Just thinking of when i could recall such an area of low pressure in the atlantic http://www.meteociel...?&ech=36&mode=0 ,

http://modeles.meteo...8-12-13-0-0.png

Oh,which led to this

http://modeles.meteo...8-12-31-0-0.png

http://modeles.meteo...8-12-31-0-2.png

Exactly. Impossible to draw conclusions either way at the moment, but all the pessisim is probably due to everyone expecting a Jan 2010/ Dec 2010 'event' in every winter month.

The models look pretty set on average/mild weather for at least the next week or so.

This winter has been far from uninteresting so far. 12 days in, and (round here) there have been 5 or 6 frosts including about 3 really severe (picture postcard style!) ones. Temperature was minus 6 in the rural spots driving in this morning. Last couple of days must have been virtually ice days. We had a light covering of snow last week which lasted over 24 hours. Some atmospheric fogs. Maybe expectations have been pitched a bit high.

So anything but boring so far. Nothing of great excitement on the way in the next week, though the chance for people to get out and about and do their Christmas shopping in relatively mild conditions might be a good thing. Have a hunch - based upon nothing really other than experience - that in about a week's time, there will again be interest in the 120-192 timeframes appearing.

[Absolute Zero]

But, if we had had the computers able to model this scenario in advance in 1978 would they have predicted that outcome? Probably yes! Is there anything resembling this being modelled at the moment? No.... but we can hope.

At this range? I don't think so.

[Frosty.]

O/T

I don't know why the models are showing predictions after 00z 21.12.12 it's going to be irrelevant

Not sure I agree with that, the models have always been much better at predicting mild weather so maybe it will become generally mild until the new year, one thing I do know, the models are abysmal at modelling cold weather and especially siberian highs.

[PMPhotography]

Did it!!! I live in the north east and it delivered zip mate!! Im not sure about the extreme south east and you can correct me if im wrong but i think it deleivered nowt down there too!!

That's unlucky! Even more so was me stuck on a bus on the North York Moors for 5 hours travelling Whitby to Scarborough. Feb 12 was certainly the best part of winter in this part of the North East!

[TEITS]

The only positive I can find this morning is with regards to the modelling of the PV in FI. Thankfully the GFS continues to back away from placing this over Greenland with the chance of a negative AO developing towards the latter part of this year.

So it looks as though very little chance of any cold spell from now until xmas but just maybe towards the end of Dec we may see a change from the zonal, mild train.

[Frosty.]

I'm trying to decide which model is worst for cold prospects this fine frosty morning, I think the gfs and ecm are both as bad as each other although at least the gfs throws coldies a few crumbs around christmas day with a risk of a northerly..which of course fails, synoptically, it looks like a milder pattern is now locked and loaded until next year with hardly any frosts and any wintryness confined to the scottish mountains.

[TEITS]

it looks like a milder pattern is now locked and loaded until next year with hardly any frosts and any wintryness confined to the scottish mountains.

Im not sure I agree with next year considering +384 takes us to 29th Dec. I agree in the run up to xmas but I wouldn't rule out a cold spell from Dec 28th onwards simply because of the timeframe but also the modelling of what happens to the PV and the heights across the pole.

[TAFKAP]

Everyone needs to snap out of it. Why oh why is it so hard to remember a few basics before reaching for the razor and baring your wrists.

1) The models do not dictate the weather. The weather at the particular period in time the model data is gathered dictates the models.

2) The models are not better at predicting mild. The UK is more often than not mild so predicting a more likely outcome inevitably leads to a better 'success' rate.

3) FI will ALWAYS be FI until we develop computers that are orders of magnitude more powerful and gather data covering more of the entire atmosphere.

3) (a) Has no body learned anything from the last couple of weeks? Weather can only be predicted accurately a few days ahead, especially in the UK.

On the positive side this is the best time of year for mild. The weather allows people to travel to see loved ones and may prevent the UK slipping into a triple dip recession due to reduced economic output from lost spending over the Christmas period.

Also the 'big' winters of 62/63 and 47 began after Christmas so plenty of time yet. Would everyone please cheer the heck up, stop having such a short memory and think of the bigger picture. Much love.

[Frosty.]

Im not sure I agree with next year considering +384 takes us to 29th Dec. I agree in the run up to xmas but I wouldn't rule out a cold spell from Dec 28th onwards simply because of the timeframe but also the modelling of what happens to the PV and the heights across the pole.

It's more about trends than timescale, the gefs 00z mean is very underwhelming with winds mainly from a swly quarter throughout, this morning the gfs and ecm ops are pretty abysmal for cold prospects but lets see what the 6z shows.

[Alex]

The upcoming mild spell was always likely, the recent sharp warming in the stratosphere has even replaced by a rapid cooling.

http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/html_e/pole30_n.html

This is supported by a ever reducing angular momentum (hardly conclusive to blocking).

http://www.esrl.noaa.gov/psd/map/images/reanalysis/aam_total/gltotaam.sig.90day.gif

The only straw to clutch is the MJO heading

Into phase 1, this can support a blocking signal.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml

These teleconnections do support a revitalised PV, its where it sets up that will be the important factor!

[Skeggy Winter Storm]

Everyone needs to snap out of it. Why oh why is it so hard to remember a few basics before reaching for the razor and baring your wrists.

1) The models do not dictate the weather. The weather at the particular period in time the model data is gathered dictates the models.

2) The models are not better at predicting mild. The UK is more often than not mild so predicting a more likely outcome inevitably leads to a better 'success' rate.

3) FI will ALWAYS be FI until we develop computers that are orders of magnitude more powerful and gather data covering more of the entire atmosphere.

3) (a) Has no body learned anything from the last couple of weeks? Weather can only be predicted accurately a few days ahead, especially in the UK.

On the positive side this is the best time of year for mild. The weather allows people to travel to see loved ones and may prevent the UK slipping into a triple dip recession due to reduced economic output from lost spending over the Christmas period.

Also the 'big' winters of 62/63 and 47 began after Christmas so plenty of time yet. Would everyone please cheer the heck up, stop having such a short memory and think of the bigger picture. Much love.

well said i totally agree the weather will always be one step ahead of the models Never the other way round

[Katiewombat]

Everyone needs to snap out of it. Why oh why is it so hard to remember a few basics before reaching for the razor and baring your wrists.

1) The models do not dictate the weather. The weather at the particular period in time the model data is gathered dictates the models.

2) The models are not better at predicting mild. The UK is more often than not mild so predicting a more likely outcome inevitably leads to a better 'success' rate.

3) FI will ALWAYS be FI until we develop computers that are orders of magnitude more powerful and gather data covering more of the entire atmosphere.

3) (a) Has no body learned anything from the last couple of weeks? Weather can only be predicted accurately a few days ahead, especially in the UK.

On the positive side this is the best time of year for mild. The weather allows people to travel to see loved ones and may prevent the UK slipping into a triple dip recession due to reduced economic output from lost spending over the Christmas period.

Also the 'big' winters of 62/63 and 47 began after Christmas so plenty of time yet. Would everyone please cheer the heck up, stop having such a short memory and think of the bigger picture. Much love.

Have to say this is the most sensible past I have read I in days. I am 100% Coldie, otherwise I wouldn't follow netweather from September to may each year. B but there are so many reasons that the snow fest is better wished for after Xmas.

That said I still have a hunch that we are all in for one hell of a surprise. Based on purely on instinct.

Katie

[Gibby]

Good morning. Here is the report on the 00z output from the big computer weather forecasting models of GFS, UKMO, GEM and ECM for this morning Thursday December 13th 2012.

All models are in full agreement on a change in the next 24-48 hours to much milder, windier and unsettled weather as Low pressure is programmed to move in off the Atlantic towards the British Isles carrying a series of rain bearing fronts NE followed by brighter and more showery conditions which last then through the weekend.

GFS then shows the start of next week with Low pressure filling in the proximity of the British Isles maintaining rain at times in temperatures well up to the seasonal normal. A ridge transfers East over Britain towards midweek bringing a drier interlude West to East with it before a freshening Southerly wind ahead of the next depression develops soon after with rain and mild air returning NE across all areas to end the working week. Into FI and the Christmas week the weather looks like remaining decidedly unsettled with Low pressure to the North carrying a series of troughs East over Britain with further spells of rain followed by showers for all. The Christmas period on this run looks mild and wet though colder conditions could work South over Northern Britain with some snow risk for the higher ground there as a Low pressure exits East into the North Sea. By the end of FI cold weather looks as far away as ever with a broad Westerly flow and occasional rain in mild conditions continuing for all.

The GFS Ensembles show a relatively mild and wet two weeks to come with 850 air temperatures well up to average and above at times with copious rainfall as successive deep Atlantic depressions cross by over or just to the North of the UK.

The Jet Stream shows a strong Jet streak racing over the Atlantic towards France which then persists for some time. Later next week the flow buckles and takes on a more sine wave appearance as Low pressure take a slightly more Northerly track though still influential to all of Britain.

UKMO for midnight on Wednesday shows a deep depression to the west of Ireland with a broad and mild SW flow pushing troughs NE across the UK with rain and strong winds followed by showers the order of events at this point in time.

GEM for next Wednesday shows a very unsettled picture and just offers another variation on the theme of potentially wet and stormy conditions as deep low pressure areas affect the whole of the UK with temperatures well up to average.

ECM finally shows a similar synoptic setup to UKMO with a brighter interlude next Tuesday before another deep depression to the West of ireland drives troughs NE with heavy rain and strong winds at times. This run shows a disturbing trend of a trailing front straddling Southern Britain for several days with an area of slow moving heavy rain causing flooding issues next Friday. The run ends with Low pressure right over the UK with no end in sight at that point of anything drier and colder.

In Summary this morning the models continue to paint a very active spell of mobile Atlantic weather to come over the run up to, and including the Christmas period. With a succession of depressions coming across the Atlantic their fronts will cross all areas with some regularity with periods of heavy rain punctuated by showers, heaviest in the SW and west of Britain. Only very short drier and brighter interludes are to be expected in such a pattern with little risk of any substantial frost, fog or snowfall due to temperatures remaining near to or just above normal after today and tomorrow in the North.

[BLAST FROM THE PAST]

A good post from TAFKAP except one misconception made by vast majority. The wintry weather in the two great winters DID NOT start after Christmas. Dec CET 1947 3.1C, 1962 1.8C. Decembers were both cold too and last 6 days of the month would not drop the CETs to well below average unless the month was running at or below average in the first place. Agreed re 62/63 the blocking structure with severe cold rapidly developed late just before Christmas as it was a NW'ly cool flow generally before that. 1946 had a successful cold easterly incursion just after midmonth.

If anything to be cheery about is that this Dec is running below average at present and nearly at half way point. Also of note was that winter 1946/7 had a very stubborn Russian HP hanging around.

BFTP

Edited December 13, 2012 by BLAST FROM THE PAST

[spayne]

Have to say this is the most sensible past I have read I in days. I am 100% Coldie, otherwise I wouldn't follow netweather from September to may each year. B but there are so many reasons that the snow fest is better wished for after Xmas.

That said I still have a hunch that we are all in for one hell of a surprise. Based on purely on instinct.

Katie

I totally agree with you Katie.....Christmas Day is at +270 hrs, since when has anyone accepted that as gospel..??

[MR EXTREMES]

1963 didnt start until 29the december.

who would this this would turn out to be one of the coldest winters on record.

look at the mess and loads on here including myself would be screaming winters over and uncle bartty with heights over europe and deep lows in the alantic soon changed read all about it on the link below amazing stuff.

Edited December 13, 2012 by model rollercoaster

[Snowman.]

FI still looks good although the models don't anything in terms of cold we have several things that will help us down the line.

1) Trended warming in the 10Hpa Strat which is seen by the GFS for a number of days and the ECM is starting to pick it up aswell.

2) Arctic High has been thrown around in the Charts recently and looks better with every run.

3) Many have been alarmed of the PV moving to Greenland but this is more of the case that GFS just goes to Default in FI, we are now starting to see it become more displaced again and move to Russian/Scandinavian which should favour in Greenland ridging.

[Timer]

1963 didnt start until 29the december.

who would this this would turn out to be one of the coldest winters on record.

look at the mess and loads on here including myself would be screaming winters over and uncle bartty with heights over europe and deep lows in the alantic soon changed read all about it on the link below amazing stuff.

I beg to differ. The 1962-3 winter weather began on Boxing Day 1962 (in my neck of the woods anyway, living in Surrey at the time). I remember it well!

[Great Plum]

A lot has been made about temperatures being mild next week... Outside of Devon and Cornwall, this is not mild...

http://www.wetterzentrale.de/pics/Rtavn13217.png

Neither is this... (Ireland and part of Wales as well excepted...)

http://www.wetterzentrale.de/pics/Rtavn15617.png

Edited December 13, 2012 by Great Plum

[No Balls Like Snow Balls]

It may well be turning unsettled but it's not going to be paticulary mild across the majority of the UK and in strong winds it will feel pretty chilly one suspects.

It could be worse :-)

[abruzzi spur]

1963 didnt start until 29the december.

That was a very short year then - what happened to 1 January to 28 December?!

AS