General Model Output Discussion

[Frosty.]

Reading through some of the regional threads it looks like the thaw is well and truly on as temps have already risen a couple of degrees above freezing!

It's a balmy 0c 32f here in wakefield

Fingers crossed the ecm has the better grasp of the current situation but whichever model proves correct this coming week, more snow to come and scotland probably hanging on to the coldest weather for longest if the gfs verified.

[Great Plum]

Bit of a misconception when people use the term "thaw", you can have a thaw without it actually getting mild ie its still cold ie say 2C to 3C but a slow thaw.

My apologies Mr Data, it was probably wrong of me to call it a thaw because it is still cold and much of the snow is still around... it's a bit well... 'drippy' at the moment...

Will this affect things further up the line?

[Weather-history]

The BBC countryfile forecast could be a nightmare, today!

I think the GFS hasn't been especially brilliant at the medium range recently. It never really went for the snow freezing rain in the south just before Christmas, it pushed the milder air too far north after Christmas and it never really grasped the easterly.

[snowmadchrisuk]

My apologies Mr Data, it was probably wrong of me to call it a thaw because it is still cold and much of the snow is still around... it's a bit well... 'drippy' at the moment...

Will this affect things further up the line?

The Met Office say Thaw by day , Ice by night .

[West is Best]

Reading through some of the regional threads it looks like the thaw is well and truly on

It's a complete whiteout here. Been snowing for some hours and really heavy now.

Which is where, with the models, I think we do need to acknowledge that there's nothing genuinely mild in the offing at all.

[Cecil Hogmanay Melchett]

I'm not happy with the output this morning.

I think the majority of us are going to be seeing rain/sleet/wet snow today and tomorrow.After that it doesn;t look like getting any colder unless you class FI as hopeful.

[mushymanrob]

what you say about 'not as cold Mushy' is essentially correct-there is no way the intense cold of the past 4-5 days could be carried on even without the probable effect of the low to the SW.

However, its very very complex-and a situation not seen for many years, not this side of the millennium for sure.

When was the last time that ALL parts of the UK had 5 days cold or very cold air sat over it. That is just for the more SW'ern areas-move North and east and, especially for parts of central Scotland and the higher areas of England that 5 days is almost 5 weeks!

Mild Atlantic air will of course win-but whether its this week or next month is the crunch. A forecasters nightmare as I keep repeating.

At the moment I would think that away from the SW and some western coastal areas the following 2-3 days MIGHT see an almost forgotten classic frontal snow belt, with probable blizzards over some of the higher areas, even in the south. Watch the radar over Europe, see how heavy the precip is, watch the 925mb temperatures as much as the 850mb ones. The higher end of the atmosphere, 700mb upwards is not of any direct concern although obviously it is part of the overall attempt by the milder Atlantic air to push the frigid air east and north.

A week of fascination to weather watchers.

thanks for that john, i agree its very interesting in the comming days ahead. my problem locally is that 'cold' is no use for snow, even now theres a slight thaw (at 1.4c). as i see it, MY 'big freeze' is all but over.

Hi Rob,

Long time no speak!

I suspect around 7 days to a more seasonal feel to around 7-8 degrees which may see some serious

flooding in places.....

Not our favorite Bartlett weather but I must admit to see the true Greenland High and some proper

Winter synoptics has even got me captured even though I prefer warmer conditions!

The kids wanted cold so I caught the bug

I explained what would happen when we got our Bartlett and they frowned...When I explained

what a TRUE GH gave...eg possible SNOW...They said..bring us that!

Hope you are well mate and possible milder Feb on way?

Regards,

CV

tbh ive enjoyed these conditions, i dont like being cold but it isnt winter without some wintry weather. my fav winter was 81-2 where we had a month of severe winter at the right time then it turned nice and mild... a repeat i hope this year!

france is shivering like us,

but will warm up before us and before the less cold weather gets here ...

next weekend looks pretty mild on the gfs 00z... especially sunday, before normality returns. afterwards its looking like a pretty normal winter..

[Eugene]

Which is where, with the models, I think we do need to acknowledge that there's nothing genuinely mild in the offing at all.

Yes certainly staying cold throughout the coming week, less cold than last week of course but i don't think you can keep weeks up that are 6C below average for too long and the coldest start to January since 1894

Alot of posturing on TWO saying thats it for cold blah blah blah, the same people who wrote off anymore cold after the pre christmas cold spell, need i say more.

[ANYWEATHER]

Even the great freezes the likes of 1962/63 which was the coldest winter since 1740 had some days when the temperature climbed above freezing! Anyway nothing in my eyes has changed a classic battleground situation and of course the models will struggle with this has they have not had to contend with these synoptics for decades! Yes this week will see rain perhaps freezing rain for some but for most the precip will mainly be the white stuff...!!

[mushymanrob]

the coldest start to January since 1894

is it?.... really colder then jan 82?... not here its not thats for sure, my coldest temp was -7c.

[Matt12]

It seems like there has been a pretty serious downgrade since last night. Even in the short-term (i.e. within the next few days), the BBC are going for milder conditions. This is backed up by the ensembles, which suggest that warm-up is imminent, with milder air working its way across the UK within the next few days to the extent that coastal parts already have a high risk of seeing rain/sleet instead of snow. Still time for the models/weather to change though, I guess. Certainly a big backdown since last night though, by the looks of things.:lol:

Edited January 10, 2010 by Matt12

[cooling climate]

is it?.... really colder then jan 82?... not here its not thats for sure, my coldest temp was -7c.

If you look at the archive charts the cold spell in 1982 did not arrive untill the 06.01.82, in the south

anyway.

[Weather-history]

If you look at the archive charts the cold spell in 1982 did not arrive untill the 06.01.82, in the south

anyway.

Yes, it got very mild at the start of January 1982

[bluearmy]

looks like a slow slow breakdown from the sw which may never really become a breakdown as the continental influence reaserts itself after the first one or two attempts to push the trough through. impossible to tell where the troughs will run out of steam but i think the further northeast you are, dont expect too much snow from this. fascinating. the T84 FAX this morning shows the shortwave closer to ireland than last nights T96 and no disruption to the occlusion over n france. i expect this to chop and change a bit over next 24 hours. anyone fancy making the countryfile forecast today??? i hope whoever does it will be vague and explain why. slow warm up from very cold to cold. slow thaw by day, frost by night is a pretty reasonable and safest summation.

[cooling climate]

Reading through some of the regional threads it looks like the thaw is well and truly on as temps have already risen a couple of degrees above freezing!

The fax for Wednesday (link below) shows much milder westerlies for the south western quater although no doubt there will be snow on the eastern flank of the front.

Still, with all the snow in some areas I guess a gradual thaw over the next few days is better than a suddern warm up.

http://www.wetterzen...ics/brack2a.gif

Inland temperatures of +1c does not constitute a thaw in my book. As for coastal areas they were expected to rise

2or 3 degrees above freezing for the next 24 to 36 hours.

Certainly we have lost the deep cold but a thaw, I don't think so.

Another good run this morning from the ECM and it is this model that has nailed this cold spell so far with the

UKMO a close second.

They are the ones to watch I feel.

[johnholmes]

Inland temperatures of +1c does not constitute a thaw in my book. As for coastal areas they were expected to rise

2or 3 degrees above freezing for the next 24 to 36 hours.

Certainly we have lost the deep cold but a thaw, I don't think so.

Another good run this morning from the ECM and it is this model that has nailed this cold spell so far with the

UKMO a close second.

They are the ones to watch I feel.

yes the term-lost the deep cold seems about right to me.

Its pretty obvious I would have thought that if temperatures are above freezing then some kind of 'thaw' Will lake place. Unless the temperatures get above about 4C then its a slow one certainly not rapid.

The weather seems to show no signs of becoming mild by definition in any time scale.

Regarding the precipitation-I continue to suggest that slight intensity-outside the exceptional cold values at 850mb for most of last week, almost always lead to a 'wintry' mix-rain, sleet, frozen raindrops, rain. For snow to fall in the conditions we are now in then height is required and/or intensity. Both will give snow, maybe wet rather than the dry variety of the past week but snow but not with very slight intensity at any low level, near the sea or not.

[MP-R]

Obviously this could change nearer the time but it's such a shame that such a deep high to the east of us can't put a fight up against the rather petty Atlantic:

http://www.wetterzentrale.de/pics/Rtavn2161.html

Let's hope signs of a reload that were there yesterday come back.

[swilliam]

It seems like there has been a pretty serious downgrade since last night. Even in the short-term (i.e. within the next few days), the BBC are going for milder conditions. This is backed up by the ensembles, which suggest that warm-up is imminent, with milder air working its way across the UK within the next few days to the extent that coastal parts already have a high risk of seeing rain/sleet instead of snow. Still time for the models/weather to change though, I guess. Certainly a big backdown since last night though, by the looks of things.

No real downgrade or backdown - temps were always predicted to be slightly above freezing for today with DPs around zero. If you were going by BBC they were predicting about 2C in many areas in England and Wales.

If you were going by BBC they were predicting about 2C in many areas in England and Wales.

Looking at the uppers there is a small pool of colder air to come over us today - which could enhance the snow potential.

The only downgrade has been the lack of snow which I think was a forecasting error.

Looking later in the week as well it was always likely that there was going to rain/sleet round the coasts - the amount depending on the exact track of the low which is still yet to be decided. I must say the the +84 Fax does not look good from that perspective with certainly some milder air coming into the SW - as I say this is still quite a way away for this event yet.

Thereafter the GFS does bring in some milder air next weekend but then reverts to a huge HP to our North in FI (not normal winter as someone erroneously stated above).

ECM does not bring in any mild weather at all.

As someone correctly stated above in the previous very cold winters many days were just above freezeing with uppers around 0-(-5) but surface cold. It was only when cold pools spread that there was continuous frost and these only usually lasted a few days. So I hope that every time the temp goes up slightly people are not going to go about and the end of the cold spell and the breakdown. That to me is when the block is completely displaced back into Europe and we have mild (at least with temps near average) Atlantic winds over most of the UK>

[SMU]

So what you're basically saying is the normal even larger teapot whimping out of a cold spell.

No Im not saying that--- All im saying is the general theme of the weather looks to be becoming quiter- & slightly less cold-

We have a gentle thaw today-- it depends also what model you use- you cannot use consesus today as theres to much variability- going from the warm GFS to the cold ecm-

The ECM is still the model of choice & I personally dont expect any great inroads of warmer air into the UK- other than the Extreme SW tip & possibly Ireland later on-( if the winds swing Southerly)

Chart of the day so far-

Mondy...- Agree with the irony a little bit- however I do only get excited when theres something in the models to actually get excited about!!!!!!!

WIB- nice to see heavy snow in the SW corner this morning....

S

[WINTRY WALES]

No Im not saying that--- All im saying is the general theme of the weather looks to be becoming quiter- & slightly less cold-

We have a gentle thaw today-- it depends also what model you use- you cannot use consesus today as theres to much variability- going from the warm GFS to the cold ecm-

The ECM is still the model of choice & I personally dont expect any great inroads of warmer air into the UK- other than the Extreme SW tip & possibly Ireland later on-( if the winds swing Southerly)

Chart of the day so far-

Mondy...- Agree with the irony a little bit- however I do only get excited when theres something in the models to actually get excited about!!!!!!!

WIB- nice to see heavy snow in the SW corner this morning....

S

So no chance of this low bring heavier snowfall in from the south west later in the week then Steve?? Is the differences in the models making this too hard to call at the moment

[Liam J]

i would tend to side with the model that is showing the milder putput atm rather than the one thats coldest which seems to become everyones favourite until its churns out milder charts.

temps are rising quite fast now with many areas above freezing, quite a number of 4c now even some inland areas with elevation are 3/4c for me this is the start of the end with a thaw taking place, any snow will be reserved for the hills this week.

and i am looking forward to milder weather, safer for driving/walking.

[johnholmes]

I'll no doubt be as popular as a skunk in a very small bag but it has to be said. I've just posted this in the Yorks etc thread as there seems a lack of realism in there also-no doubt in the other regional threads.

I find some of the comments on this regional thread and the model thread pretty amusing.

What we have this morning was correctly predicted about 5 days ago. The deep cold going and being replaced by +ve daytime temperatures, slight precip and that of sleet or at best wet snow, frost unlikely after late Saturday evening.

What have we got-precisely that-so why the consternation?

I've plotted outputs from Extra and NMM daily and its not done at all badly-it has failed to get the minimum values I've had but other than that its done okay.

I suggest a closer and more objective look at the models for some people and an acceptance that the various models will show slightly different end solutions. The trick is being objective and plotting a 'middle' path. That way there is less chance of thinking something is going to happen when the reality is its not going to.

As to what is likely through the latter end of the week then its not going to get mild anywhere other than the far SW. Will the cold return, whatever that means. If you mean the bitter cold with -12C 850's, then that currently looks unlikely as there is no source of such cold air. That is not to say it cannot develop as a result of the weather most of Europe and Scandinavia has experienced for the past 7-14 days-it can. In the meantime we have to live with a more traditional British winter scene-heavy snow in places, especially over high ground with a more wintry mix for southern lower lying areas and the lovely fluffy snow many of us had for several days becoming rather slushy by day and horribly icy when we get an overnight frost.

I'll go now before I get lynched!

Edited January 10, 2010 by johnholmes

[weather eater]

While we may be getting model divergence, the GFS seems pretty adamant out to the mid range.

[cooling climate]

Can you really pick and choose which model, just to give you the answers you want? It's like cheating at exams, the only person you cheat is yourself.

3" reduction of snow cover overnight, temps of +2ºC and lots of dripping water = thaw in my book.

It is not a case of picking and choosing, I was referring to the models that have verified best during

this cold spell that is all.

[Iceberg]

GFS 06Z very similar to ECM and the 168-180Z charts scream fresh easterly to me, Strong southerly Jet, Weak upper WAA past iceland draging the High further NW and a cold pool developing over the continent being dragged towards us.