Model output discussion - 1st December onwards

[knocker]

3 minutes ago, chrisbell-nottheweatherman said:

From my point of view, a mean is of most use when the spread of data is somewhere nearly evenly-distributed.  If the data is clustered with none of those being close to the mean, it's apt to be misleading, as it suggests a middle-of-the-road result is favoured when the data actually supports one or more clusters of data towards the fringes of the spread.  I'm speaking generally here, as I don't have much experience with ensemble means, but what I'm saying is that I'd imagine that, in unstable setups, the mean by itself may be misleading.

Yes this is a road that has been well travelled Chris.

Edited December 27, 2015 by knocker

[stewfox]

6 minutes ago, on the coast said:

Wow some serious s.h.i.t building from 168 onwards. Fascinating to see what direction it will take in the next few days.

Good summary of the last 22 pages 

Edited December 27, 2015 by stewfox

[Liam J]

Minus 10 850's into Shetland at T216, cold pool heading north!!

 

 

 

 

 

 

 

Edited December 27, 2015 by *Sub*Zero*

[MPG]

19 minutes ago, chrisbell-nottheweatherman said:

From my point of view, a mean is of most use when the spread of data is somewhere nearly evenly-distributed.  If the data is clustered with none of those being close to the mean, it's apt to be misleading, as it suggests a middle-of-the-road result is favoured when the data actually supports one or more clusters of data towards the fringes of the spread.  I'm speaking generally here, as I don't have much experience with ensemble means, but what I'm saying is that I'd imagine that, in unstable setups, the mean by itself may be misleading.

It is misleading and just better to skip past and ignore the clear agenda. People posting the finer details of the output are great to learn from than just a broad brush approach.

Edited December 27, 2015 by MPG

[January Snowstorm]

Poor 18z run for coldies.

Shows how things could easily turn out mild and we remain in the current pattern.

[Frosty.]

Fascinating times ahead of us with coldies at last seeing potential for colder weather in the near future on the Gfs 18z. Things could become very interesting by next weekend onwards. At the very least it looks like we are going to lose the very mild mush for more seasonal temps and then there is the potential for something much colder. 

[mountain shadow]

4 hours ago, January Snowstorm said:

Poor 18z run for coldies.

Shows how things could easily turn out mild and we remain in the current pattern.

Yes. You can see why the Met Office weren't interested.  

 

[Hotspur62]

Is the 18z a trend away from a much colder set up??. only time will tell but I don't think we will know till Weds at the earliest as the models get a grip on how strong the High is to the NE and how strong the Atlantic train is. I find it fascinating times ahead watching how the models handle things and it makes a pleasant change from the monotonous weather the UK has endured( particulary the poor souls in the NW) over the last month.

[Captain Shortwave]

The set up on the pub run could bring some decent convective interest with plenty of heavy, thundery showers on windward coasts due to the very low heights over the UK. The south west looks particularly prone given the position of the low. It does try to turn cold briefly around day ten as low pressure becomes centred to the east of Scotland.

Rainfall totals could be a real concern here with some very active frontal systems thrown in for good measure. Not feeling too keen on this set up (too winter 13/14 looking) and hopefully the pub run has overdone the low heights over the UK during week 2.

12z Parallel also out now

Snow for Scotland and northern England at times during this period, very wet across the south with near normal temperatures again. 

Similar theme across the model runs with an elongated area of low heights stretching from the Atlantic into Europe looks likely as we enter week 2 with low pressure on a more southerly track, the question is can we get the jet far enough south. At this point I don't think anyone want to be too far south in this set up as you could get a lot rain.

Edited December 27, 2015 by Captain Shortwave

[tight isobar]

As the ecm this evening "doesn't guarantee certain cold incur

One suite of tge gfs (18z) "doesn't" mean its game-set-match.

The whole obstacle is far more complex as is our maritime weather as a whole. ....

Bundles of model resolve ahead! 

[booferking]

Would the fax charts be a good tool to use @120 as it is human input.

[swilliam]

5 minutes ago, Hotspur61 said:

Is the 18z a trend away from a much colder set up??. only time will tell but I don't think we will know till Weds at the earliest as the models get a grip on how strong the High is to the NE and how strong the Atlantic train is. I find it fascinating times ahead watching how the models handle things and it makes a pleasant change from the monotonous weather the UK has endured( particulary the poor souls in the NW) over the last month.

 

Unless it goes pear shaped then I do not think this will be resolved until about T96 which by my reckoning will be about Friday

[Cheshire Freeze]

21 minutes ago, January Snowstorm said:

Poor 18z run for coldies.

Shows how things could easily turn out mild and we remain in the current pattern.

The 18z isn't mild....but it isn't bitterly cold either. NH pattern looks good and there's intermittent snow threat- more especially over high ground.

[knocker]

We can certainly do without this.

[Frosty.]

5 minutes ago, CreweCold said:

The 18z isn't mild....but it isn't bitterly cold either. NH pattern looks good and there's intermittent snow threat- more especially over high ground.

Agreed, this is the most interested I have been in the models so far this winter with at least the potential for cold weather, surely something potentially better on the horizon in this horrible freakishly mild flood fest we have seen so far!! 

[Nick F]

The ECMF London ens look a lot more positive than the Debilt in Holland, the deterministic close to the average and quite a few colder members in there:

 

 

[mb018538]

Great....looks like we're trading mild wet and windy for cold wet and windy instead. Loads of low pressure, loads more rain for those who could really do without it. I can understand why the bbc and meto don't fancy a cold outcome. Looks to me we will be sat in the trough again for a while longer.

[feb1991blizzard]

3 minutes ago, Nick F said:

The ECMF London ens look a lot more positive than the Debilt in Holland, the deterministic close to the average and quite a few colder members in there:

 

 

That suggests that the colder members do not deliver an Easterly then?  Maybe from the N?

[mulzy]

24 minutes ago, CreweCold said:

The 18z isn't mild....but it isn't bitterly cold either. NH pattern looks good and there's intermittent snow threat- more especially over high ground.

Snow over high ground - no thanks.  If we can't a proper lowland freeze I'd rather have mild south-westerlies and low heating bills.  Cold rain does nothing for most on here!

[Nick F]

7 minutes ago, feb1991blizzard said:

That suggests that the colder members do not deliver an Easterly then?  Maybe from the N?

Well, the De Bilt deterministic and the coldest members go a lot colder at 2m than London (as would be expected), it's just there is less support for the frigid surface cold at the end of the deterministic further east over Holland than there is for it to turn colder like the det over London, if you catch my drift?

 

[feb1991blizzard]

Just now, Nick F said:

Well, the De Bilt deterministic and the coldest members go a lot colder at 2m than London (as would be expected), it's just there is less support for the frigid surface cold at the end of the deterministic further east over Holland than there is for it to turn colder like the det over London, if you catch my drift?

 

Cheers, yes sort of, it would be great if you could have the runs colour coded like the GEFS members are on the ECM but also for de bilt wind direction as well but beggars cant be choosers I suppose, I do detect looking at the latest GEFS suite a bit of a downgrade in terms of short term cold (ive quickly been through the suite) although the mean at D15 actually increases the heights just to the East of Iceland strangely, I know its not what most want to hear but to me it looks like in the end patience will be rewarded wrt a cold second half of winter!

[Paul White.]

Since this is now the moaning and ramp thread. And the met office and media thread combined. Can people please stop banging on about what the met office are and ain't buying. This may come as a surprise but I and I'm sure many others come here to read about the model output. With contributions from some fantastic posters. This is not a dig at the met office or their fine posters who post in here.  It's just we know what the MO thinks I have the app and I read about it in the thread that is dedicated for that discussion. Thanks for reading this silly rant 

 

Paul 

[blizzard81]

43 minutes ago, knocker said:

We can certainly do without this.

Ironic post indeed! Unfortunately, this is the kind of weather to expect during mild winters!

[bobbydog]

i think that by this time tomorrow, we could be looking at a completely different set of wiggly lines

 

[damianslaw]

Easily the busiest day in this thread all winter so far - usually a sign the models are showing cold evolutions..

What can we take from todays offerings? A change is taking place is best way to describe things as we head into 2016: 

• Cold pool digging into SE Europe clearing away the stubborn euro heights.
• High pressure building strongly out of NW Russia heading into scandi and further north putting a block on low heights heading to the NW.
• Potential for trough disruption or low heights taking a more southerly course over the UK with colder uppers getting in on the scene meaning either way temps at least back down to the seasonal average.

There does appear to be a pincer attack taking place on the PV both from heights over N Russia but also over N Pacific. For now though we may well remain at the mercy of the atlantic trough rather than any continental outbreak, but importantly a very differently positioned trough, one which aided by the position of the Jetstream should usher in much more in the way polar air than tropical air, heightening the risk for wintry precipitation especially in the north, and temps for all back to what we would normally expect for the time of year which will make it feel very cold compared to recently.

Longer term - there are good building blocks developing for something possibly much colder further down the line.