Model output discussion - after the beast, what next?

[Purga]

38 minutes ago, feb1991blizzard said:

GFS not looking as good, lower heights too far south - still not bad for Southern Half but just that less people will get snow.

But you had all the snow last time ! Much of the south missed out.

[feb1991blizzard]

Of course it isn't sinking run by run on the UKMO but its already very far South anyway.

[bluearmy]

It’s Tuesday afternoon

saturday is four days away

how can anyone be arguing (debating) re snowfall distribution at this range ???????!!!

btw, there is a terrific feature on meteociel call ‘live compare’. It doesn’t work  for me on mobile IOS. You can click through the different models (and runs) for the same timeframe to see how they differ re placement of everything 

Edited March 13, 2018 by bluearmy

[Mucka]

19 minutes ago, Snowy L said:

That's because you live directly to the west of the Pennines aka one of the most protected areas from an easterly. Areas much further North than you got tonnes of snow.

True enough but see my post above. There is no comparison to this afternoons modelled Easterly and the Beast we just had as far as convective snow opportunities further North.

It really should not of been a controversial statement to say that it will be a non event for snow in Northern regions if 12z GFS and UKMO are on the money - blend UKMO and GFS and it is obvious, the flow is rapidly cut off and high pressure in too close proximity to allow for snow.

It is fair to challenge that NE England could see something but personally I see the window of opportunity being small even there.

All this said, I am commenting on this afternoons GFS and UKMO, nothing to say they will be correct and things could be corrected back North and West.

Edited March 13, 2018 by Mucka

[ukpaul]

The GFS is a poorer outcome for all areas but misses the south and Scotland out regarding the major snow potential, leaving the midlands and the north as a favourable area. The better run for those areas was the 00z which was a much expanded area of instability, such as below. ICON still pretty good for the whole country at various times, though and the UKMO misses everybody!

Edited March 13, 2018 by ukpaul

[feb1991blizzard]

1 minute ago, Purga said:

But you had all the snow last time ! Much of the south missed out.

Exactly, the last setup was conducive for my location. insanely low 500mb heights with at times a storm force Easterly wind, the GFS wouldn't deliver anything meaningful and the UKMO nothing at all.

[frosty ground]

7 minutes ago, Mucka said:

 

It was but if you are going to call a reasonable analysis bed wetting what can you expect in return? (But it's not reasoned it's factually incorrect)

Where did I say it was worse than the 06z? (see below)

I commented that if. and it's still a big if, UKMO and GFS are on the right track then it will be a non event for Northern England as far as snow is concerned. (But the 12z GFS has corrected north, i have also shown 4 runs worth of PPN charts showing for the same time period that show PPN over Northern England, i also made the comment that the 0z PPN charts looked out of kilter with the other three runs)

I didn't say it won't be cold (I never said you did, or did I?) , it certainly will be and it is an amazing synoptic for time of year but other than a very short window of opportunity in the NE there is very little chance of lying snow for anywhere away from the SE half of Britain, extending into some central regions. (based upon what charts?)

I really wouldn't expect NE England to get lying snow form UKMO and unlikely even with GFS but that is arguable, North Western areas would have virtually no chance of lying snow. 

Basically the further N and W you are away from the SE then the less likely you will see any snow falling let alone lying.

We can't compare this

with this.

When making assumptions about snowfall.

If I were in the SE I would be less bothered as there is far more wiggle room.

 

(brackets for responses)

[snowking]

12 minutes ago, bluearmy said:

I assum that’s ukv rather than ukgm. Anyone know ??

 

I don't think the UKV goes out that far Nick, so I would assume the view out to 48 hours (which shows hourly forecast intervals) would be UKV and then possible it would be the GM thereafter? Either that or some kind of MOGREPS-R output, but I would have thought GM more likely

Either way, as always to anyone less experienced, I would treat these (and any hourly app type forecast for that matter) with the disdain they deserve. They're probably at their most useful printed off and then used as loo paper

Edited March 13, 2018 by snowking

[nick sussex]

I wonder whether we’re seeing an issue with observations on certain runs .

The same thing happened yesterday with the UKMO.

The evening run was further south than the morning , this morning it got shunted further north then back south again this evening .

Given the other outputs so far  it does look like an outlier and was last to even be interested in the cold air even making it further west.

I’d stick with what the ECM projects as that’s been leading the way so far .

[frosty ground]

8 minutes ago, feb1991blizzard said:

Look at last nights 18z, then the 0z, then the 6z, it is.

But it's not, the 12z is further north than the 06z, it's not even debatable, so it's not creeping south with every run.

 18z Run

 0z run the high is actually further north

The 06z did move south of the 0z and 18z run, but the 12z has pretty much moved back to where the 18z was.



 

[stewfox]

4 hours ago, Purga said:

06z GEFS for London as an example, almost matching the Beast Mark 1.0 levels of cold intensity!

-13 / -14C uppers strongly supported + decent precipitation spikes as well = ❄️❄️❄️

BBC will have a field day again

Bozo the dog is found safe

 

Impressive GFS chart for 9am Sunday, if only it was January

Edited March 13, 2018 by stewfox

[feb1991blizzard]

3 minutes ago, nick sussex said:

I wonder whether we’re seeing an issue with observations on certain runs .

The same thing happened yesterday with the UKMO.

The evening run was further south than the morning , this morning it got shunted further north then back south again this evening .

Given the other outputs so far  it does look like an outlier and was last to even be interested in the cold air even making it further west.

I’d stick with what the ECM projects as that’s been leading the way so far .

I actually think yes the UKMO is too far south but also think other models too far North, I reckon the ECM ensemble mean has the correct steer on this.

[bluearmy]

5 minutes ago, snowking said:

I don't think the UKV goes out that far Nick, so I would assume the view out to 48 hours (which shows hourly forecast intervals) would be UKV and then possible it would be the GM thereafter? Either that or some kind of MOGREPS-R output, but I would have thought GM more likely

Either way, as always to anyone less experienced, I would treat these (and any hourly app type forecast for that matter) with the disdain they deserve. They're probably at their most useful printed off and then used as loo paper

the output changes too often to be ukgm  kris

[feb1991blizzard]

1 minute ago, bluearmy said:

the output changes too often to be ukgm  kris

Yes, it changes every 3 hours.

[Captain Shortwave]

21 minutes ago, Mucka said:

True enough but see my post above. There is no comparison to this afternoons modelled Easterly and the Beast we just had as far as convective snow opportunities further North.

It really should not of been a controversial statement to say that it will be a non event for snow in Northern regions if 12z GFS and UKMO are on the money - blend UKMO and GFS and it is obvious, the flow is rapidly cut off and high pressure in too close proximity to allow for snow.

It is fair to challenge that NE England could see something but personally I see the window of opportunity being small even there.

All this said, I am commenting on this afternoons GFS and UKMO, nothing to say they will be correct and things could be corrected back North and West.

To be fair NE England still looks good for a light covering from this, again posts suggesting the SE could get battered are not backed up by the models, areas south of the Wash are predicted to get nothing from the GFS with Lincolnshire and the Midlands favoured for the highest totals as a streamer develops across the Wash. Areas as far north as Northumberland look good on the GFS for a light covering.

The UKMO again stalls and sinks the cold pool into France on the flip side by day five the cold pool is  south west of Ireland on the GEM. Hard to call this one with large differences on the timing and track of the cold air.

      

Also it is worth adding that the front which will slowly move across the UK at the end of the week will push across us again on Saturday which could bring some light snow for many as it moves west.

Edited March 13, 2018 by Captain Shortwave

[seabreeze86]

Come on everyone let's keep it civil until the model which obviously has this nailed the NASA comes out 

Edited March 13, 2018 by seabreeze86

[bluearmy]

Just lost five minutes of my life checking the ukmo pre the last beasterly and people’s memories are skewed by the second push of cold which was further north than the initial blast. Ukmo was a bit south at T144 but thereafter it was pretty good.

[Weather-history]

36 minutes ago, bluearmy said:

It’s Tuesday afternoon

saturday is four days away

how can anyone be arguing (debating) re snowfall distribution at this range ???????!!!

btw, there is a terrific feature on meteociel call ‘live compare’. It doesn’t work  for me on mobile IOS. You can click through the different models (and runs) for the same timeframe to see how they differ re placement of everything 

Yep

I saw snow flurries from this set up early last month, SW of Manchester. You wouldn't even think I would see anything from this. 

[Derecho]

2 minutes ago, Captain Shortwave said:

To be fair NE England still looks good for a light covering from this, again posts suggesting the SE could get battered are not backed up by the models, areas south of the Wash are predicted to get nothing from the GFS with Lincolnshire and the Midlands favoured for the highest totals as a streamer develops across the Wash. Areas as far as Northumberland look good on the GFS.

The UKMO again stalls and sinks the cold pool into France on the flip side by day five the cold pool is  south west of Ireland on the GEM. Hard to call this one with large differences on the timing and track of the cold air.

      

Yup I can see where Mucka is coming from to some degree but I think the increased solar heating would spark of more convective snow showers, that's the difference with where we was two weeks ago. Plus remember how many runs didn't pick up on that polar low during Monday with the last beast? Only ECM was picking it out really until really close to the event.

We wouldn't want any further corrections south and the UKMO isn't so great compared to other runs we have been seeing, though this isn't something that will be resolved until later on tomorrow I reckon. I've also been impressed by the consistency of the ICON which means the prospects of a snowy spell are still very much there IMO.

Anyway here is the swingometer for the latest bunch of runs. The runs which have unstable air crossing the UK tend to prolong the cold, whereas those that don't tend to sink the high so we see a slow warm up. Such runs appear in the minority now as the Atlantic appears to be waking up towards the end of next week but that could still change. Admittedly more prolonged cold with retrogression to Greenland has taken a step back.

[Daniel*]

It’s fair to say this is record breaking cold at least recorded on GFS 12Z with 510 dam into SE would be a monumental effort in January let alone mid March, the CET is going to take a tumble.

And just following earlier beast outrageous really. History repeating itself a tad. 

[Jayfromcardiff]

2 hours ago, abbie123 said:

South East England looks to be sweet spot regarding snow ..

You said that last time and still ended up with less than Wales and the south west? 

[ICE COLD]

T96 ECM 

And here is T120 

Looking very good to me ?

Edited March 13, 2018 by ICE COLD

[Mike Poole]

Key frame on ECM tonight for me is the T120.  

Looks a bit middle ground to me given other output.

Edit: T144 the high sinks.

Edited March 13, 2018 by Mike Poole

[January Snowstorm]

All models agree this evening on a cold frosty and mainly dry setup. 

Of course some coastal snow showers also

[ICE COLD]

T144 is a bit ?