Model output discussion - here comes the beast!

[karlos1983]

Oh my, look at this for a graph!!

THE BEST THIS WINTER BY A COUNTRY MILE

Look at the mean, sub zero 2mT, rarer than rocking horse ****

Edited February 22, 2018 by karlos1983

[Glacier Point]

33 minutes ago, bluearmy said:

not taking much from deep fi gfs in a reverse zonal correcting back to zonal atmospheric environment - however, it does present a new idea which is when the westerlies recover themselves somewhat as the neg NAO subsides, we could have a residual decent ‘wedge’ meandering east which could help to prolong the cold spell and take us to a slidergate scenario approaching mid March 

Do think the idea of small 'cold' ridges appearing over Scandinavia and to our north is a sound one once this initial cold incursion wanes. And that's before our next proper influence from the strat warming is felt.

[A.J]

just caught up with 30 odd pages of model posts....jeez!.....It's not often that I'm lost for words (just ask the wife) but blimey what a gobsmackingly ramptastic set of runs we've had the past 24 hours.....How many times have we ever been able to say that a 'beasterly' is locked in?.....Sounds good doesn't it?....lol....deep cold arriving at T96 and the ECM?....wow, blizzard machine with a channel(ish) low a bit further down the road.....Yes, for the latter, a pinch of salt is needed as it's still bordering on the edge of FI, but let's face it, with that much snow potentially, a thousand truck loads of salt still wouldn't melt it....lol...................................One thing though, it's very rare we get this kind of weather pattern occuring so let's all take time to savour it and not look for the end of it, otherwise the famous NetWeather winter quote will have to changed to "Get the cold in first, and the inevitable plank posting about a breakdown will follow".....lol

In closing, I asked for an expert second opinion of this upcoming spell of weather, and the great news is that Olaf says ...... 

 

[Altostratus]

Just been going through the GEFS and there are some real blinders in there. Out of the entire suite there are maybe only 2-3 runs where the brutal cold in the second wave doesn't hit the UK. It is also clear that there is a growing trend for lows to encroach from the south further enhancing the gradient.  

[bluearmy]

3 minutes ago, Glacier Point said:

Do think the idea of small 'cold' ridges appearing over Scandinavia and to our north is a sound one once this initial cold incursion wanes. And that's before our next proper influence from the strat warming is felt.

If only it was a few weeks earlier Stewart - could have really been looking at a month to rival some of those in the seventies/early eighties (ignoring 47/63)

lets look forward to what we have over the next couple weeks anyway - the London eps T2’s fit the 30 dayer which stays clustered cold to 6th at least 

[Frosty.]

Something tells me there's a nationwide freeze (Beasterly) on the way!!..doesn't the GEFS  6z mean look sensational!

[stodge]

7 minutes ago, Glacier Point said:

Do think the idea of small 'cold' ridges appearing over Scandinavia and to our north is a sound one once this initial cold incursion wanes. And that's before our next proper influence from the strat warming is felt.

This has been modelled at medium range on both GFS yesterday and ECM today. It seems reasonable to suppose the residual cold pool left over Scandinavia will encourage, in the absence of a strong PV or northern jet, the formation of "cold" HP cells analogous to what we see over Greenland. The question is whether these will have any impact on a returning Atlantic.

I also noted GFS trying to build HP just to the north of the British Isles on a more southerly tracking jet.

I think there will be a return to milder conditions in the south and west in the second week of March but this "could" be transitory IF HP re-asserts to the north or north-east.

[supernova]

GFS ensemble shows Op and Control very much at the milder end of the spectrum beyond the initial plunge. Good.

[Nick F]

Good morning, and what an exciting time for weather nerds awaits us as we head through next week.

First up, a browse of the 00z EC London T2m ens shows the op goes sub-zero for the max on Thursday 1st March, so a very cold start to Spring in the Big Smoke.

Notice also the op is on the mild side of the spread for Saturday 3rd March - when that low it shows drifting N from Biscay pulls in less cold air across SE UK.

The models can often be too progressive in removing cold air, and next week the cold will be deep and well entrenched too over northern Europe including UK/Ireland, so not sure I buy the quick removal of cold from the south, particularly as the upper flow looks weaker further north over Europe too, with the jet displaced over SW Europe.

Looking at snowfall potential next week, can't really be specific and pinpoint anywhere that will see most snow, other than generally across eastern coastal counties. 

There is a broad consensus between GFS and EC for shower distribution early next week, albeit can't go into too much detail, so don't take ppn charts below literally.

Using the 00z EC, it looks like Monday will see snow showers towards eastern coasts, perhaps most frequent north of E Anglia, flurries possible further south too.

Tuesday looks like the beginning of perhaps more widespread heavy snow showers and/or more organised areas of snow moving in from ENE and penetrating well inland, EC op runs a disturbance SW from NE England down toward Wales and the SW. GFS doesn't have this feature as such, but still piles in the snow showers towards eastern areas.

Rest of the week really not worth going into detail, suffice to say plenty of snow showers towards eastern areas, perhaps further troughs getting these snow showers further inland at times.

EC teases us with the low moving up from western France on Friday, associated fronts would bring heavy snow, to southern and central areas, but low confidence on this, lows could stay over France and snow confined to far south.

One final note, it will feel perishing in the wind by the middle of the week

 

Edited February 22, 2018 by Nick F

[Frosty.]

The Ecm 00z ensemble mean is the best yet!..high further north, nobody would miss out on this upcoming severe wintry spell..hope this continues and next week produces the most extreme icy / snowy blast nationwide that we've seen since 2010!!

[Purga]

A clear shift in the GEFs 06z towards colder and extended cold solutions as compared to the 0z run albeit that the Op & Control go the less cold route earler on still.

0z                                                              6z

A lot of scatter later on.

Edited February 22, 2018 by Purga

[Glacier Point]

This is the sort of synoptic I would be looking for around the t300 mark.

That's around the time our second downwelling pulse should be making itself felt. Not what those of us hoping to be going to Cheltenham the following week will be wanting.

[tight isobar]

6 minutes ago, Glacier Point said:

This is the sort of synoptic I would be looking for around the t300 mark.

That's around the time our second downwelling pulse should be making itself felt. Not what those of us hoping to be going to Cheltenham the following week will be wanting.

Certainly wont be wanting to back anything that likes cut in the turf.. #solid #cheltenham..?

[Rayth]

Think our PM discussion may well have jinxed the festival @Glacier Point 

Problematic if you’re anywhere near right ! 

[Man With Beard]

38 minutes ago, karlos1983 said:

Oh my, look at this for a graph!!

THE BEST THIS WINTER BY A COUNTRY MILE

Look at the mean, sub zero 2mT, rarer than rocking horse ****

You'll never see a better ensemble for cold this side of the channel.

Look at that for 1st March - clustering maximums between 0C and minus 4C. And that's London! It'll be colder away from there.

Remember - March temperature record is -4.6C. Unless there's a quick turn around in the models (looking less and less likely), it could go. 

[mrmonopoly]

2 minutes ago, tight isobar said:

Certainly wont be wanting to back anything that likes cut in the turf.. #solid #cheltenham..?

What is that likely to cause ? 

[tight isobar]

1 minute ago, mrmonopoly said:

What is that likely to cause ? 

Plenty withdraws(non -runners)..

#likely!!!!?

[mrmonopoly]

Just now, tight isobar said:

Plenty withdraws(non -runners)..

#likely!!!!?

I was thinking more about the weather not the horses haha

[stodge]

3 minutes ago, Raythan said:

Think our PM discussion may well have jinxed the festival @Glacier Point 

Problematic if you’re anywhere near right ! 

There was an inspection on the first day in March 2013 due to frost. They'll obviously put down frost covers but if they get covered in snow it starts becoming an issue.

Gold Cup day was lost to snow in 1977 or 1978 as I recall.

[East_England_Stormchaser91]

2 hours ago, SizzlingHeat said:

The low in the Azores is concerning for prolonging the cold. Looks to make inroads towards tail end of the week again....

As I've mentioned, an Azores low is 10000x better than a typical nagging, stubborn Azores high, and a big governor of the NAO. An Azores high will generally mean a +NAO. The Azores low has always been a common feature in some of the most historic cold spells. 

[Djdazzle]

3 minutes ago, East_England_Stormchaser91 said:

As I've mentioned, an Azores low is 10000x better than a typical nagging, stubborn Azores high, and a big governor of the NAO. An Azores high will generally mean a +NAO. The Azores low has always been a common feature in some of the most historic cold spells. 

As long as a strong Azores high goes back to its home by the summer, I don’t mind! 

Great models again today so far. I’m normally fairly cautious, but next week could be special. It’s already got that continental feeling down here with a noticeable east wind.

[ICE COLD]

WOW JUST BLOODY WOW ?. 

Only just caught up this morning . The wife's gone away , so I'm on house wife duty and school runs etc ?. 

The runs just keep getting better and better . Look at these from the ECM .

Amazing charts . 

GFS = very cold and very snowy 

ECM = stonking cold and very snowy 

UKMO = very cold and snowy 

All that again = A STONKING METO UPDATE AGAIN ???

we are in for a truly memorable cold spell . 

[SteveB]

42 minutes ago, Glacier Point said:

This is the sort of synoptic I would be looking for around the t300 mark.

That's around the time our second downwelling pulse should be making itself felt. Not what those of us hoping to be going to Cheltenham the following week will be wanting.

I wonder when the last time Cheltenham was can cancelled due to snow.

[Weather-history]

1 minute ago, SteveB said:

I wonder when the last time Cheltenham was can cancelled due to snow.

1987 Gold Cup was delayed because of a heavy snow shower.

[SteveB]

4 minutes ago, Weather-history said:

1987 Gold Cup was delayed because of a heavy snow shower.

So a good 30yrs ago then.

We really are looking at a record breaking event here, I wonder just how many records could fall.