Winter Model Discussion 18Z 13/1/13 onwards.

[pages]

JMA follow the Ecm

[weather_it_will]

right being an absolute novice can someone guide me to a place on the site where i can learn as to how to read the charts and stuff please?? sorry to be a pain and write this in here!

Try here... http://forum.netweather.tv/forum/24-learning-about-weather-and-meteorology/

[Cloud 10]

right being an absolute novice can someone guide me to a place on the site where i can learn as to how to read the charts and stuff please?? sorry to be a pain and write this in here!

Secondly this blast we are due later in the week, any ideas about how the NW may do or what its looking like currently? Had no snow in Liverpool to speak of, few bits of it mixed in with sleet and rain.

Cheers and if this is on the wrong board my apologies as im not sure where to put it

Learning about weather and meteorology - Netweather Community Forums

[Spah1]

Hi all,

First time post. Just wanted to say I have loved the last 10 days reading all the analysis. I read on some of the weather websites that the weather forums were getting excited about a SSW so I thought I'd try and learn more. It appears I jumped on board at the right time. I thought reading Angels and Demons was unputdownable on a recent holiday in Turkey but following the analysis has been enthralling. I thought I loved cold and snow but you guys and girls take it to a whole different level. I've found myself waking in the middle of the night and wondering if the GFS 00Z has upgraded our snow potential! I didn't even know it existed 10 days ago.

Looking forward to everyone's analysis of the hopefully upcoming event on Friday / Saturday and the rest of the Winter.

Keep up the good work from a happly converted newbie!

[frankie01]

thanks guys

[karlos1983]

Seemed to be a statement at odds with the actual output didn't it, unless he is only looking out to 120?

Not that I think ECM or especially GFS has this right.

GFS has already proven to be very progressive when compared to even its own set of "progressive" ensembles - on that level I think its garbage though the broad pattern is plausible.

ECM will probably be on the "mild" side (though chilly) of its London ensembles from 144 to 192 (goes colder thereafter as the block reasserts itself) but unfortunately it may not be that clear and would show better either with the 850 ensembles or much further West with the 2m ensembles much like GFS Op has an obvious "mild" bias when you view it through the 2m ensembles for the South and West being virtually constantly above the mean in the important phases.

Overall the output is heading toward a snowdown near you this weekend!

I have no model bias but I really wouldn't put any faith in GFS output at the moment and would side with the Euros for guidance if I had to put a professional forecast out.

Cheers for that Mucka, appreciated.

[BLAST FROM THE PAST]

JMA.....Oof you bugger. UKMO like this model too

BFTP

[TEITS]

Excellent 12Zs this evening.

I haven't much time to post but the outlook is becoming clearer in my opinion. A big snow event for some followed by a brief return to less cold conditions followed by it turning colder again. Greatest risk of becoming less cold is the SW, best chance of remaining cold is Scotland. However that detail is bound to change because the positioning and orientation of this attack from the Atlantic is bound to change especially once inside +72.

Once this barrage from the Atlantic weakens which it will eventually do then a very good chance of it turning bitterly cold from the N/NE/E. Probably around 25th Jan onwards at the moment.

[MR EXTREMES]

More snow at 144hrs on the ECM, surface flow would be se ahead of the precip.

Much better shape to the troughing than the GFS.

can i just ask how is there more snow at t144 with uppers like this ....

[Captain Shortwave]

ECM follows UKMO to an extent but not as far in the earlier stages. I don't want to dismiss GFS by any means as it could still be right, but to me it seems to be making the same mistake as last week. We have a split in energy and whilst most models takes most of the energy south East, GFS takes this east/north east. Same situation, same split in model runs.

[cooling climate]

Just mentioned about the SSW not really showing its hand int the models yet

and then up pops the ECM t216-240 and from there a very cold blocked pattern

would emerge.

The UKMO and now ECM are continually showing better undercutting and more

amplification to the north.

The cold isn't going anywhere.

[snowking]

can i just ask how is there more snow at t144 with uppers like this ....

Easterly flow off the near continent = less modification of dew points and temps

Low Heights = shallow system = -5c NOT required for snowfall (could feasibly snow up to -1 or even just below 0c 850 uppers dependant upon vertical profile

SK

[Jason H]

Low level cold and dew points from the continent!

Beaten to it by SnowKing.

Edited January 14, 2013 by Jason H

[Froze were the Days]

UKMO looks the best at 96z and with the Atlantic depressions somewhat further west would allow for better undercutting and THEN we would be in for a shout with real cold easterlies, ECM progs the block strength more to the east and the milder air up the west side of the country but still a battle to be had in FI. What I want to know is why the GFS is so consistent with the Atlantic coming in from the west and the other models not?, this has been happening for days!

[weather is fun]

Very confusing posts tonight. So is the cold staying or going? Sounds like some are saying mild to break through on the models. Yet others say cold going nowhere. Very confused. Please help.

[nick sussex]

I do hope we see that drop down of cold into the USA around 144hrs, this plays an important role for the UK.

What this does is help to elongate the PV, it also acts to amplify the pattern temporarily upstream, this then helps sharpen the troughing near the UK.

Take a look on the NH charts for the big 3 at 120hrs and then 144hrs to see the effect of that amplifying wave.

[Snowman.]

i think the model outputs are poor from north midlands south and although i did see snowfall this morning its far from classic its also worth noting the alantic has powered up massively in the last few days with the increased likely hood of an quick breakdown from the west but those in the far eastern side could well have the joys of a winter wonderland.

i think we are certainly going to be the parking place for deep low pressures beyond the weekend with those north of the low pressure systems then seeing the cold with blizzard conditions certainly over high ground.

all in all very poor outlook with some unwelcome rain to southern england until we see a lull in the alantic im afriad it seems no heights can build to our north i think with the nao being positive its not really aiding us like the 09/10 winter which was neg for sometime.

the start warming this time has not really done the uk any favours so far can it produce the goods well im rather dissapointed so far but theres nothing to say its possible but im sceptical this year.

the vortex is very subbon lets hope for futher developments around the end of jan.

Errr another post like this.

the strat warming has done something other wise we would be in raging swesterlies or just westerlies the SSW can affect us down the line too as this is the initial response too the SSW we have more too come so do let your hopes down if you didnt see anything today as there is plenty of time.

Last year it took 9 days for a real change this also took around the same but this seems better. NH of the gfs hints height rises over the pole and nearly nothing left of the vortex

This would leave us in a very negative AO and a also a negative NAO.

You can see from this chart if it went on a couple more frames we would begin too see ridging around greenland.

So don't you say that the SSW had no effect on the weather because it has just giving us a small cold snap which has given some there first snowfall of the season.

[Mini tiger]

Does anyone think the deep low over northern Scandinavia is helping keep the high pressure further south west

and in turn keeps the low pressure to our south west as well. Hope for South West England then

[Froze were the Days]

I don't mean to be pessimistic but going by the modelling so far this winter, pick the best looking model in terms of cold and longevity and bin it because that's the way it's been so far - ECM might be closer to the mark but who knows!

Great model watching (it seems like this winter has gone on yonks and we're only 1/2 way though).

[MR EXTREMES]

Just mentioned about the SSW not really showing its hand int the models yet

and then up pops the ECM t216-240 and from there a very cold blocked pattern

would emerge.

The UKMO and now ECM are continually showing better undercutting and more

amplification to the north.

The cold isn't going anywhere.

and this is the charts ive been looking for ecm t240 is what i call the holy grail,

hopefully the models will be showing more of this although its way way to far out,

even the 12z tonight past 72hrs are fi in my opion after the dissapointment of the uk met fax downgrading massively on convective snow fall mid week,

although better for the northern half of england and the eastern side for the weekend.

but once them polar heights play ball i be happy.

[mcweather]

can i just ask how is there more snow at t144 with uppers like this ....

For the reasons snowking outlined above the great sw Blizzard of feb 78 left 25 foot drifts and buried the southwest for days happened with uppers of minus 2

[MR EXTREMES]

For the reasons snowking outlined above the great sw Blizzard of feb 78 left 25 foot drifts and buried the southwest for days happened with uppers of minus 2

ok atleast ive lernt something extra tonight.

so there for the ecm ukmo are exciting charts.

[swfc]

Very confusing posts tonight. So is the cold staying or going? Sounds like some are saying mild to break through on the models. Yet others say cold going nowhere. Very confused. Please help.

The outlook between now and thursday is staying very cold with the odd snow shower at the east coast.towards the end of the week things could turn very snowy towards the south west and maybe further north.after that it looks uncertain but the trend. is for the cold to stay with further snow if the blocking remains strong and the low pressure goes sse

[Chess01]

Has the ssw shown its effects yet and are we going to see more prolonged cold as we get to then end of jan

[Summer Sun]

Need to keep an eye on the end of the week now as the Atlantic trys to push in but hits the cold air giving a battleground scenario for the west

Into Saturday and further snow remains possible with the east likely to see further falls

By the afternoon and evening the snow turns back to rain in the far south west and wales later in the afternoon

All in all lots to play for at the end of the week with some significant falls of snow possible

Edited January 14, 2013 by Gavin.