Winter Model Discussion - Cold Hunting -12Z 03/01/13

[syed2878]

good evening guys. How relyable is the cfs model? Frm wht i red before frm ian f's posts the our met dnt touch that model, or am i talking crap if i am then guys i stan to be corrected. Thx.

[Frosty.]

The Gfs 12z is having a stab at changing the pattern by T+240 with a disrupted jet and cold blocking to the northeast, it then goes wrong as a vigorous low moves up from the southwest and bitterly cold air from the east is well to the north of the uk but there is hope for a colder second half of the month, as for the next week, mild until probably the middle of next week then trending cooler, the northwest being most unsettled, the southeast being driest and brightest with only small amounts of rain, then temps dropping to around average with a risk of slight frosts and some mist/fog for at least southern britain, windier with rain and showers further north. Then it looks like pressure will rise more generally with the north joining the south in a drier pattern with chilly nights, that takes us to mid month onwards when the chance of a colder spell should increase.

As for the second half of the month, the metoffice are still hinting at a marked pattern change later in the month and that is where all coldies hopes rest.

Edited January 3, 2013 by Frosty039

[-uksnow-]

Not a bad profile at 192, wheres that AH going...?

Edit: Steve beat me too it

Edited January 3, 2013 by -eded-

[on the coast]

http://www.meteociel...H1-192.GIF?03-0

Atlantic high pressure has that infamous tilt towards greenland at 192...

S

Looks very good on Wetter although well in to FI I suppose. Cant wait to see the late weekend charts.

[Panayiotis]

Looking much better on the ECM at 216 compared to the 00z, I wonder if that low can send heights towards Greenland but with -4C uppers covering all of the UK, it will feel cold under a light northerly wind.

Edited January 3, 2013 by Panayiotis

[Ian Brown]

Looks very good on Wetter although well in to FI I suppose. Cant wait to see the late weekend charts.

I don't think it does because the Azores High has nowhere to go from T192, still, a little bit messy and time for changes.

[Mr Frost]

good evening guys. How relyable is the cfs model? Frm wht i red before frm ian f's posts the our met dnt touch that model, or am i talking crap if i am then guys i stan to be corrected. Thx.

Belongs here Syed.

The CFS is usually WHEELED out in emergencies for mild or cold lovers. It has never had a HANDLE on any pattern or trend. I would keep a LID on it and just browse at you're own leisure for a bit of fun.

Edited January 3, 2013 by Mr Frost

[BurwellWeatherWatch]

though probably best in landfill rubbish rather than recycle bin.

i don't think the meto place any credence in cfs

[kev238]

Clearly there are changes afoot and there is a lot more hope for cold and snow than there was a few days back! It will be intriguing to see where a block sets up.

[nick sussex]

Good GFS in the higher resolution, the UKMO totally underwhelming at 144hrs, the ECM has a great upstream pattern at 240hrs with that deep low heading ne through the USA but down stream is poor.

The rest of the outputs are a mix of good and not so good for potential. So a mixed bag with more questions raised than answers.

[Panayiotis]

So at 240hrs, the ECM did nothing which I suggested, as there was to the west of low near Iceland stopping any heights from going northwards and instead this low, flattened the HP a little, but looking at the bigger picture, its still good, with a 1050mb high at the pole, and another ridge starting to form to the east of America.

Edited January 3, 2013 by Panayiotis

[Buzz]

From reading some of the posts here, it seems that some people really need to read/re-read Ian Fergusson's post on page 2 of this very thread:

http://forum.netweat...20#entry2462809

Edited January 3, 2013 by Buzz

[Duane S.]

Over the past few days I've been posting, when I can, a couple of pretty looking GEFS member charts for January 15th. In that time I've found he good ones have got increasingly better and bad ones have lessened in quantity...

Then there is the control. Very different in that it goes for a rather nice looking Easterly...

I love seeing this as it widens our margins. December was Easterly or bust. Here we have a much widen scope (at the moment) of where HLB could set up. Happy days.

[Cloud 10]

Belongs here Syed.

I'm prepared to give it a chance of redemption!

[Fozfoster]

I put some jokes in the "make us laugh" thread to cheer you all up in here but there was no need, things are on the up.

[Zenarcher]

Evening everyone some interesting model outputs today and things certainly looking more promising than they have been lately,

Using the GFS, ECM, UKMO, GEM, JMA and NOGAPS for comparisons.

Friday to Sunday 72 hours - The models show all of the UK can expect cloudy and misty conditions, temperatures will be on the mild side and it will be a lot more drier. Gale force winds are likely at times in the North and West and elsewhere will be breezy.

Monday 96 hours - It seems like the UKMO and NOGAPS are the odd one's out with the Atlantic low we have they form it differently,

Here is a close up comparison of the ECM and UKMO,

More models show something similar to the ECM and the UKMO seems to have it further East.

Tuesday 120 hours - The GFS, ECM and GEM all show either one or two low pressure systems form in the South of Greenland, the UKMO and JMA do look similar here they have things just slightly more East and then NOGAPS as usual showing something on it's own.

Here are what they show side by side,

I've also made up this other image of the situation over Iceland notice how the UKMO and NOGAPS are the only ones here that look the odd ones out.

Wednesday 144 hours - All the models show a deep low to the South of Greenland but again its the UKMO and NOGAPS showing something different I explain in the image below,

Overall - The models I believe are slowly picking up on something interesting but it will take a bit more time for things to start to show up. As for the models today most seem to have agreement between them but the UKMO and NOGAPS seem to have little support at the moment on their outputs when you compare them to the other models.

[IDO]

BOM showing the potential if the SSW shows a quick response:

[nick sussex]

Can anyone remember back to the last time we saw the Arctic high as to which model did a better job with that. I know the GFS 18hrs run was the first to pick up on the dreaded shortwave that was part of the easterly debacle but earlier in the winter we saw an Arctic high.

[Gibby]

Good evening. Here is the report on the 12z Output from GFS, UKMO and ECM for today Thursday January 3rd 2013.

All models tonight show a mild and moist WSW airflow over the UK around a strong Anticyclone just to the South of the UK. occasional light drizzle will continue to affect many Western and Northern coasts and hills with any brightness in the day restricted to sheltered Eastern areas where high ground lies to the West. By early next week a weak trough crosses from the west with the chance of at least a little rain for many in continuing rather mild and benign conditions.

GFS then shows further quiet weather if less mild as winds back slowly Southerly later in the week as Low pressure drifts slowly SE to the West. The West of the UK could see some rain from this as the pattern becomes complex as High pressure tries to build to the North and East. On this occasion it fails with the rest of FI showing unsettled weather returning from the West as the Jet Stream migrates South with some rather cold conditions in the North especially where some snow could fall with time especially over the higher ground.

The GFS Ensembles show a decline in uppers after this weekend with the return to nearer normal values when taken as a whole. However, this paints just half of the story as there are a notable number of members who dip to much lower values than has been seen for some time in the second half of the output. The incidence of precipitation increases somewhat too as we move through the run.

The Jet Stream shows a continuation of the Arching of the flow over the UK around the Northern periphery of the High to the South of the UK in varying degrees for the coming week or so.

UKMO for midday on Wednesday shows a large slack area of High pressure over Western Europe with a SW flow over Northern and Western parts of the UK. A continuation of the rather mild and rather cloudy weather seems likely at that point with the chance of some rain and drizzle in the North and West.

ECM shows a similar pattern at that point moving forward to show a couple of weak fronts crossing East over the UK in the broad Westerly flow with some rain and drizzle for most as they pass. At the end of the run the pattern remains quite flat with High to the South and lower pressure towards the North and Northwest.

In Summary there is still not too much to talk about for our cold loving friends tonight, at least not what's likely to be felt at the surface in the period of the output. There will be a lot of dry and rather cloudy weather still to come with a little rain at times. GFS does show the embryonic signs of a pattern wanting to change and their ensembles do show some interesting options tonight between some of their members but the ECM operational remains very uninspiring out to 10 days with the same pattern of High to the South and lower uppers to the North at the end of it's run. So all in all it's a case of waiting to see if the models respond to the SSW event over the coming days and wondering what implications that may have on the output and eventually our weather later in the month.

[Frosty.]

To put another spin on it, it looks like a tallywacker and balls ready to hmmmmm......all over Great Britain!!!

it looks like an elephant to me

Models are now churning out some very cold charts later in FI, hopefully our patience will be rewarded after mid month with a spell of extreme cold.

[AWD]

This;

could prove rather helpful combined with the Strat Warming.

[ronan]

it looks like an elephant to me

Models are now churning out some very cold charts later in FI, hopefully our patience will be rewarded after mid month with a spell of extreme cold.

It actually looks like a big Eagle coming down picking us up and taking us on a trip to the Arctic for a whole month!

[bobbydog]

Can anyone remember back to the last time we saw the Arctic high as to which model did a better job with that. I know the GFS 18hrs run was the first to pick up on the dreaded shortwave that was part of the easterly debacle but earlier in the winter we saw an Arctic high.

is it really relevant though nick? as we didnt have an SSW in the offing back then

[Frosty.]

A senior colleague literally just reiterated this key, key point: "No NWP will get a grip until SSW effects feed lower-down into model synthesis." Ignore -in effective sense of preventing any coronary - all GFS output post around mid-late next week. UKMO model equally showing considerable inter-run flux at longer reaches too (it goes to T+168 internally) and all of this is expected / symptomatic / characteristic of how they struggle with the complex dynamics of what is still at an incipient phase. Nothing, as yet, is offering anything surprising nor unexpected. So, please: NO MORE posts bemoaning any lack of profound cold showing at longer range of GFS, or EC, or whatever. It is all - stress ALL - considered effectively unreliable. Period.

Sit tight....!

HOO-RAAH

Top post IF, more and more inter-run FLUX ahead, i'm itching for the SSW effects to feed lower-down into model synthesis, there are exciting times ahead peeps. HOO-RAAH indeed

[Cloud 10]

Bom Bom Bom Bom!

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