The hunt for cold - Model discussion (late November)

[SMU]

5 minutes ago, shaky said:

Any charts steve to compare!!

120 06z left V 126 00z right

[markw2680]

1 hour ago, snowray said:

Not just that post, there are a few posts turning up saying things like what should we expect? it was all out in FI blah blah blah, don't look too far ahead you will be disappointed. And then finish off  with something like the "the signs are promising further down the line", or "the beast will arrive Christmas" or "wait for the new year" yh like it's easier to forecast out at T500 with a crystal ball I guess. Quite funny really.

 

Anyway, I will just have to stick with the JMA from now on this winter, it never once went for the easterly scenario, the new super king model! But it's all still a long way off so you never know, could be game on again by the 12z, certainly still a decent chance of a undercut or more likely battleground scenario later next week.

Well I’m not saying wait for the beast like it WILL happen just going by what the experts say there is a pretty good chance of it! All I’m saying is if we look at the models in far reaches of fi we will pretty much all be disappointed all of the time

[Met4Cast]

It’s a little early to be throwing in the towel off of the backs of 1 mornings model runs. UKMO is fairly decent

GFS mean holds the block in place longer than the GFS Det, too

And this mornings ICON is much improved upon it’s overnight run.

The Det runs do seem a little progressive when compared with their respective ensemble suites but even they eventually get the Atlantic in and then we have a low pressure signal right out to the end of the extended (day 15). 

Anything that happens after the block development is up in the air, models do historically struggle with this. If I was a betting man I’d probably bet on the Atlantic winning out based on this mornings models, however there’s still plenty of water to go under the bridge before we get to that point.

[shaky]

5 minutes ago, Steve Murr said:

120 06z left V 126 00z right

Mate that is pretty big upgrade at a short time frame lol!!that ridge looks stronger aswell!!

[Skullzrulerz]

We seem to quite in a bit of a state this morning

There's no doubt about it that overnight models have trended towards a more unsettled and near avg temps compared to a cold outlook

We shouldn't just give up just because of overnight let's see what today brings out before making a outlook 

[Duane S.]

Unless we have some members on here who have acquired the ability to go forward in time to see what the weather is going to do, I am going to continue to go by the outlandish notion that nothing has actually happened yet.

A poor (relatively speaking) few runs of late but there is plenty of time for this to switch back.

And of course further prospects remain very promising.

 

[MR EXTREMES]

and renewed wave attack at 144 onwards with gfs.

so its certainly nowhere near the be all end all by far.

still interesting 2018 perhaps even better towards mid month.

[Ventnor Viking]

On 26/11/2018 at 16:25, ICE COLD said:

Are u for real ? . Yes we’re gonna be in for some zonal for the next 10 days , but come on writing off the whole of December . I will quote your post in 10 days and I bet you it will look completely different to what we’re having now . See ya in ten days

Hi @icecold so 10 days is up........(banter btw before emotions run high)

My perspective still has not  changed. Still looking at mid to later January for anything significant and a SSW will be needed to help things along. 

Id also just like to make the point that im hunting for cold with you all but Im seeing at a slightly different time than most and that doesn't = trolling   

btw if people werent so snappy and bullish to jump on people with a different outlook to their own I would write more meaningful posts......... 

As I mentioned 10 days ago there would weak attempts and the odd transient cold period which I think is all we can expect this side of Christmas/New Year 

[Man With Beard]

Well it's gone from a quick topple a few days ago, to a fairly clear easterly with snowy breakdown in the past days, and now it's knife-edge territory with a slight leaning towards a non-snowy breakdown. The ECM mean chart at T144 shows just how close this is:

It's the positive/negative tilt teaser. Run an imaginary line through the kinks in the isobars through Ireland, and you get the incoming front. On this chart, it looks ever so slightly negative (i.e. tilting slightly west as you go north on the front). The hope from this position (for coldies) is that this front will stall, the Scandi high sustains its position and energy goes south, eventually tilting the front further back on its northern portion, and an easterly sweeps up the northern flank of the front, turning it to snow.

By T192 it's happened, but just too late to get underneath the high.

Energy goes over the high rather than under, and the high sinks:

In a sense things haven't changed massively as it has been clear-ish for days that the Atlantic would win out in the end - what is flexible is whether we get a snowy incident as that happens - odds slightly turned away from that this morning 

[MR EXTREMES]

theres a westward correction on this run and shallow heights pulling up towards greenland.

[stodge]

Morning all

Plenty of deflated individuals this morning but to try to be analytical it's worth looking at a single run and a single timeframe to see how the modelling has developed.

On Tuesday 4th, the GFS 00Z OP at T+174

A strong ridge moving north and NE across the British Isles with a large Atlantic LP retreating westwards.

Wednesday December 5th, GFS00Z OP at T+150:

The ridge is weaker, the LP over Eastern Europe deeper and the Atlantic model is different.

Now, this morning and the 00Z at T+126:

If this cold spell next week has failed, it's because the original ridging from the south has ended up weaker than originally modelled which makes the block over Scandinavia weaker and less able to withstand a vigorous Atlantic but I'd also note the modelling of the LP over the Baltic which is deeper again this morning and also inhibits the development of a suitably robust block.

The Atlantic LP was at the start moving west to the south of Greenland but the new LP coming up from the SW invigorates the energy and aids the LP in punching through the weaker block.  

[MR EXTREMES]

much better arctic northerly shallow heights to our west and north weast.

[feb1991blizzard]

4 minutes ago, MR EXTREMES said:

theres a westward correction on this run and shallow heights pulling up towards greenland.

No notable change up to 96 from what i can see.

[Froze were the Days]

Stacks of potential from day 10 onwards on the ECM 12z...but haven't we been saying that bit too much over the last couple of weeks?

[78/79]

I don't profess to know a lot about interpreting the models etc. I leave that to the knowledgeable folk on here , but my  opinion for what it's worth is  any sort of respite from this awful  Atlantic driven crud is more than welcome, and as f far as I'm concerned Winter starts on Dec 21st  despite the Met offices love for tidy statistical purposes.  Plenty of time for proper winter weather  yet,  bitterly cold weather before Christmas is like looking for Lord Lucan riding around on Shergar.

Edited December 6, 2018 by 78/79

[snowray]

1 hour ago, FetchCB said:

Not sure if its mentioned this morning but isn't this the norm for GFS.....pick up Easterly at Day 10....drop it a few days later....then smell the coffee and return with the Easterly with 72-96h to go ?

It is normally when the GFS reigns back the easterly that METO extended forecast mentions easterly and snow...and hey presto as if by magic.....

 

Yes this sort of this does happen sometimes.

Anyway looking shorter term (not FI guys, happy?), todays FAX chart seems pretty good to me at T84, HP towards Greeny looking more prominent there.

Edited December 6, 2018 by snowray

[frosty ground]

It's would be worth a mention that the correction west on the ICON is good but considering it's starting position I think this is just the models converging on the soon to be correct solution (Probably a temporary ridge thrown up that quickly gets pushed east) After all this has had support from the ensembles from all publicly available models. 

Edited December 6, 2018 by frosty ground

[carinthian]

14 hours ago, carinthian said:

Hi, not sure how they work these charts out from over 50 years ago, but I remember the night of 19th January 1963. Think it was a Saturday night and the coldest I can ever remember from a wind chill prospective. I lived on the family farm in Cheshire and kept a weather diary. At 10pm snow was blowing about in a very strong NEly and noted a temp of 17f . My dad ran home from the local pub about 2 miles away and he told me he had never been so cold in his life. Before I went to bed , I had a bath and the steam froze on the inside of the window. No central heating in those days. The following morning a foot of powder snow had fallen with drifts of 6 feet or more down our lane. What a winter that was.

C

Just an observation about that amazing winter was the milk truck always turned every morning on time as did the school bus. Our school never closed that winter. The playground was the biggest ice rink in the world, great fun. When I got home after school , I walked in the fields and stood in snow drifts and actually ran with drifting snow. When its snow now where I live one mile up in the sky, I cannot wait to get out and walk in it for hours. My wife , born in a land of snow thinks I am bonkers.

[MR EXTREMES]

i reckon greenland heights are not a done deal yet.

i think this run looking ok.

we need them split lows in the atlantic and the small feature around close to greenland to phase together allowing heights to establish itself.

[snowray]

If the useless Scandi high can shuv off asap, we might actually get a decent northerly before Christmas. 

[karyo]

Quite a change in the models in the last 24 hours. Basically the high pressure is too far east for the UK and not as strong as initially thought. To be honest, I am not gutted because the easterly looked a bit toothless (the uppers were surprisingly high for mid December).

Let's hope we get cool zonality before the next easterly opportunity arises.

[Eskimo]

Lack of posts sums it up, the GFS 06z is even worse than the 0z. Atlantic comes in quicker. 

[Dennis]

Icon gives nice pattern starting weekend

[ICE COLD]

36 minutes ago, Shaftesbury Snow said:

Hi @icecold so 10 days is up........(banter btw before emotions run high)

My perspective still has not  changed. Still looking at mid to later January for anything significant and a SSW will be needed to help things along. 

Id also just like to make the point that im hunting for cold with you all but Im seeing at a slightly different time than most and that doesn't = trolling   

btw if people werent so snappy and bullish to jump on people with a different outlook to their own I would write more meaningful posts......... 

As I mentioned 10 days ago there would weak attempts and the odd transient cold period which I think is all we can expect this side of Christmas/New Year 

Lol . Up until yesterday morning it was looking pretty good next week for cold crisp weather . Now it’s a bit . Let’s give it another 10 days and see where we are . All the signs look good going forward. 

[swfc]

At 192 hrs on the gfs 6z the pv looks in trouble to me!!!, Good heighths coming of the eastern seaboard ete.decent nhp imo