Model Output Discussion 19th January 2014-18z onwards.

[karlos1983]

All talk of battleground snow events are a tad premature imo and until we get a cold block in place over us I think thats how they will remain.  Here is a classic battleground snow set up for the south way back when, though I remember it well, it was a rip snorter...

 

 

 

 

now that's what I'm talking about!

 

or even this last year

 

[TootyFruity]

Hi sorry if I've missed the answer to this but a couple of people have mentioned the jet stream powering up again with the power off the states , how will this affect the block that's forming , will it wipe it out and return us to the constant barrage of lows and rain ?

Sorry if someone has answered this question already

TF x

[shedhead]

now that's what I'm talking about!

Can you imagine what this place would be like now given similar synoptics to those?  Frosty would have ran out of superlatives ages ago....

[Man With Beard]

now that's what I'm talking about!

 

or even this last year

 

If I recall correctly, this one didn't actually bring snow. But it set the foundations for this 7 days later, which provided beautiful snow on the south coast. 

which on the face of it, doesn't look dissimilar to some charts we've seen recently. But the cold was in place last year, this time it isn't

[karlos1983]

If I recall correctly, this one didn't actually bring snow. But it set the foundations for this 7 days later, which provided beautiful snow on the south coast. 

which on the face of it, doesn't look dissimilar to some charts we've seen recently. But the cold was in place last year, this time it isn't

 

Yes I think you are correct, I couldn't quite remember the date, but yes the general theme of what I really call a battle ground in Position A*

Edited January 23, 2014 by karlos1983

[weather eater]

Seems to me that what’s being modelled in terms of potential snowfall is not that far of what happened in March. Here we had a relatively small fall of snow, but places like the hills around Buxton had massive drifts, head towards Stockport it was just rain. I was actually out in it helping people whose cars had got stuck, there was some pretty impressive drifts and we almost got stuck ourselves on the road between Castleton and Chapel, a four by four was stuck in a huge drift and we had to take the driver and turn around back the way we had come leaving his car behind, however, once off the hills there was very little snow in places like chapel-en-le-frith and Glossop.

So yes if you have some elevation you could see some serious winteriness but I suspect it will be a mainly a slushy mess at low levels.

[EML Network]

Love the terminology - backside dynamics?

 

Does this mean they are talking out their a*** Nick?

 

HA HA HA HA HA that made me chuckle :-)

 

I think Nick has hit the nail on the head with this one and for me it's all too much on the wrong side of marginal for this neck of the woods at least. 

 

I'd like to see the High Block to the East being modelled a good few hundred miles further West hence the Low being also modelled the same.

 

It's nearly always the same with this type of set up in that everything is shunted East the closer we get and we end up narrowly missing out. 

 

The fact that the UKMO model is painting the best picture at + 144 gives me hope though, already this year the ECM and GFS have both painted a nice + 144 outcome that failed to come to pass, so let's see if it's a case of 3rd time lucky with the UKMO. 

 

The JMA 06z Run is often left out of the equation when people are posting charts so for me it's interesting to see how close the morning run is to the overnight UKMO run for the same time frame

 

so here's the JMA 06z Run for 7PM Sunday

 

And here's the overnight UKMO for 1am on Monday morning which is as close as you can get with the increments being slightly out of phase with a 06z run..

 

 

VERY little in it.

 

It does look like next week at least for a time will be the coldest part of winter 2013 / 2014 for many of us , I might actually have to put the heating on, but I'm not overly convinced many will see any meaningful snowfall from this. 

 

If I were going to pick a day when current indications favor the best chance for seeing snow I'd be looking at overnight Tuesday and into Wednesday morning, dew points look good for central England as does the Humidity levels

 

 

Although the Uppers are very much too close for comfort

It's all very close and too close to call for my liking, which normally means that elevation is key. In my opinion....as things stand anyway

[gottolovethisweather]

Hi sorry if I've missed the answer to this but a couple of people have mentioned the jet stream powering up again with the power off the states , how will this affect the block that's forming , will it wipe it out and return us to the constant barrage of lows and rain ?Sorry if someone has answered this question alreadyTF x

 

It's expected by those with far more computing power at their disposal to do just as you state above. I'm imagining the confidence surrounding this comes from upstream developments i.e. those currently taking place in the US will end up creating a thermal gradient producing deep lows which are predicted to be too powerful for the European block. Time will tell.

Edited January 23, 2014 by gottolovethisweather

[Man With Beard]

Hi sorry if I've missed the answer to this but a couple of people have mentioned the jet stream powering up again with the power off the states , how will this affect the block that's forming , will it wipe it out and return us to the constant barrage of lows and rain ?

Sorry if someone has answered this question already

TF x

Doesn't wipe out the block on this chart, it just gets deflected south. But if it keeps going through us as modelled, expect more wind/rain.

[nick sussex]

The latest GME has made a westwards correction compared to its 00hrs run and is a bit more amplified upstream, the latest NAM 12hrs looks in good support of the UKMO upstream at T84hrs.

 

Lets hope that's a good sign for the rest of the outputs.

 

As early as T48hrs and the GFS is more amplified over the central USA, this should mean the shortwave will dig further south as it moves east. So far a nice trend.

Edited January 23, 2014 by nick sussex

[Catacol]

All talk of battleground snow events are a tad premature imo and until we get a cold block in place over us I think thats how they will remain.  Here is a classic battleground snow set up for the south way back when, though I remember it well, it was a rip snorter...

 

 

 

 

Unfortunately we have an azores high at present - as pointed out by Gibby - so you are talking chalk and cheese here. 

 

And Strat forecasts for the end of next week continue to see vortex energy over Canada

 

 

with a vorticity prediction that sees plenty of low pressure action coming our way..

 

 

No - sorry. I'm still as gloomy as yesterday despite some reasonable op runs at 144. Unless we have a massive misinterpretation of background signals going on here, then cold will not be establishing itself over the UK next week. Beyond that? Who knows... but the biggest priority is to see ongoing warming attacks in the strat drive vortex energy away from Canada. There is some suggestion of that in the very long term charts yesterday, but by then we are looking at mid February and the window is getting small...

[SMU]

Early doors on the UKMO 12 & the GFS 12 sees ( around 54) the Scandi high further west & the atlantic low digging further ( GFS)

with both models show more favourable angle of the deep cold into Eastern Europe ( may come in useful down the line)S

 

 

PS catacol- the azores high will always be around in the mix somewhere- its where its displaced to is key! 

Edited January 23, 2014 by Steve Murr

[gottolovethisweather]

Whilst it's only the much maligned GFS, it starts the latest run with 18 hours of continuous rainfall likely towards the far SW of England from 9pm onwards tonight, good grief. Even those in more central parts of the UK look like seeing a full 9 hours of continuous rainfall.  The heaviest of this rainfall is initially shown over the majority of Ireland and Northern Ireland then towards the SW and Wales overnight. The rain briefly preceded by some snowfall over the highest peaks. The levels of flooding concern are raised by the fact that Saturday 25th January no longer looks a dry day away from Southern England. In fact it looks like a day of an increasingly colder Northwesterly flow bringing wintry showers further South as the day wears on. Sunday is initially dry towards the East but given the volatile profile up above this all changes and heavy flooding rain has arrived virtually everywhere by midday. My next summary, if I have time will be my take on things into FI i.e. the final working week of January.

Edited January 23, 2014 by gottolovethisweather

[Summer Sun]

Sundays low still looks nasty a lot of rain for the areas which don't need it and strong winds as well

 

[MR EXTREMES]

jet stream creeping more south with the weak ridge in and around Greenland not bad so far so good.

[karlos1983]

to my untrained eye....looks better in terms of ridge in the Atlantic and over the  Cental US at +60 UKMO

 

00z

12z

[Yarmy]

Sundays low still looks nasty a lot of rain for the areas which don't need it and strong winds as well

 

 

Yes, looks really bad tbh. Hope people are prepared.

[The Eagle]

12z looking slightly better so far. Better jet profile and LP slightly further south.

[SMU]

http://modeles.meteociel.fr/modeles/gfs/runs/2014012312/gfsnh-0-102.png?12

 

GFS 96-

 

Were in business thus far- all12z signs point towards the UKMO 00z.

 

S

[Blake]

GFS 12z for Monday morning bringing heights across north slightly further south and slightly stronger over Greenland, Scandi high MARGINALLY further west (1015, 1020 and 1025mb kinks over Norway and Sweden) and the centre of the low to our NW 30 miles or so further south.

 

6z

 

 

12z

 

 

Positive steps I'd say?

[Summer Sun]

Looks like the easterly is still on

 

 

Showers turning increasingly wintery in NE Scotland and higher ground in England

 

[gottolovethisweather]

The Easterly is certainly on as this particular GFS run is peachy in its early stages once the four consecutive days of flooding rain and showers are out of the way. Much better prospects for a period of cold weather unfolding IMHO.

Edited January 23, 2014 by gottolovethisweather

[SMU]

Sorry for the commentary

 

UKMO 96 - Awsome

 

http://www.meteociel.fr/ukmo/runs/2014012312/UN96-21.GIF?23-17

 

Draw your eyes towards Southern Norway & the deep cold angle.....

 

S

[Summer Sun]

12z looking better than the 06z at t120

 

 

06z at the same time

 

 

Showers turning increasingly wintery for Scotland

 

Edited January 23, 2014 by Summer Sun

[fergieweather]

Thanks for your updates as ever, tis good to receive a privileged viewpoint on things in here. However, part of what you state above has me confused and it's the bit I've highlighted, can you explain things further when you get a moment. 

 

How can higher confidence be ascertained after a period of lower confidence beforehand. Maybe I'm being a bit of a nitwit but I don't get your statement.

 

Aside from all that, from what you've consistently suggested I believe you forsee a right ole mixture going forward with still some sort of battleground in the meantime but with the Atlantic expected to break through eventually.

 

I'm sure the Dep. Chief won't object to me citing him directly on his briefing issued just before midday today (the emphasis italics are his, not mine), so to avoid paraphrashing or confusing the UKMO underpinning behind the 6-15d forecast. This should speak for itself re your queries and why a return to zonal is the form horse further ahead:

 

"...after a quasi-meridional period in approx the day 6 to 8 day f/c period in which a filling area of low pressure moves SE’wards across UK, there is a return thereafter to the generally zonal pattern already seen for most of this winter. There are differences between models.... wrt the detail of the return to a more zonal pattern, but very little disagreement that this broadscale evolution will occur.....

Examination of Shannon Entropy f/c output from both EC and MOGREPS both have low entropy / high confidence early in the 6-10 day period and later (in the trend period), with a spike of high entropy / low confidence around days 8 or 9, relating to

the detail of the return to zonal flow."

Edited January 23, 2014 by fergieweather