Model Output Discussion - 12th December Onward

[Matty M]

Could evening friends.

Watch the bouys and synopsis out in the Atlantic to see if any changes are afoot for the system.

Still has the potential to be a severe storm for southern England and i maintain this.

Is there any other bouy site, surely there must be more buoys in the Atlantic then illustrated here?

http://www.ndbc.noaa.gov/

[weathe20]

Well to give you an example it is currently Snowing in Weston Super Mare right now , came as a surprise as we were suppose to have less chance than yesterday , and were A costal resort in the South West ... On Current charts Rain to Snow possible just about anywhere . Down here today the heavy ppn is making a huge difference . The track of the low will effect who get's Snow showers over the weekend also as it will depict the exact direction of the flow coming in IMO

Its not snowing in weston super mare, its rain with a little bit of sleetyness.

Models showing the low in the same position as earlier, it would have to take a big shift in the output to head much further north. My thinking the track will be slightly further south again.

[Paul_1978]

Seems to me that basically we are in for a northerly regime at the weekend, then next week we evolve into a westerly, then south westerly pattern (as per Ian Brown), but then at Christmas possibly back to square one, ie blocked Atlantic, and a north westerly pattern again.

Also as of lunch time today, there are NO warnings for snow from the Met Office for this week.

[legritter]

morning gang ,computer still playing up but new one in new year hopefully . virtual memory crap . could someone please tell me what CMS ,ENS ,CHARTS ARE AND how accurate ,interesting developements to our west ,can see cloud tops now sun is higher ,.if all the elements come together thurs /fri it could be knife edge time . this is the type of low i like with colder air to our east and high pressure over scandi ,will we have melt down tonight ,cheers thanks in advance .

[snowmadchrisuk]

Its not snowing in weston super mare, its rain with a little bit of sleetyness.

Models showing the low in the same position as earlier, it would have to take a big shift in the output to head much further north. My thinking the track will be slightly further south again.

It was snowing as I headed from Filton through temple meads and bedminster about an hour and a half ago . Current temp in bristol is 1 deg . I also think a track further South , For people in the midlands the worry would be how far North the PPN can get.

[Radiating Dendrite]

morning gang ,computer still playing up but new one in new year hopefully . virtual memory crap . could someone please tell me what CMS ,ENS ,CHARTS ARE AND how accurate ,interesting developements to our west ,can see cloud tops now sun is higher ,.if all the elements come together thurs /fri it could be knife edge time . this is the type of low i like with colder air to our east and high pressure over scandi ,will we have melt down tonight ,cheers thanks in advance .

Pardon?

The cold air is actually to our NW and there is no scandi high.

The CMS is a long range model that is very volatile and not very accurate (beyond trends). The ENS are the alternative GFS and ECM runs that are fed different starting information to the main run, producing slightly differing outcomes.

Edited December 14, 2011 by Radiating Dendrite

[Uncle_Barty]

Snowfest for the midlands it's looking more likely with each run. Meteogroup ( don't know what model they use) backing up the NAE by forecasting heavy snow for my area on Friday. I have never seen these and the GFS to be wrong in such a short time range. If the met officea do issue a heavy snow warming, it's nailed IMO.

Snow is NEVER nailed until it actually falls. Especially down south.

[Thundery wintry showers]

I think the ECM is the solution we need to hope for, with the upper high getting far enough north. The GFS can sometimes be overzealous with westerly set-ups and doesn't always clock the northward extent of blocks. i've seen Bartletts turn into Scandi highs over the period of 5-7 days of model runs...so we'll see...

Yes- I remember having a disagreement with you re. high pressure earlier in the month (which turned out to be moot as it never materialised lol) but on this occasion with high pressure building to the north-east and troughing over Europe, I think conditions are rather less conducive to a Dec '06/07 type "sinker" than might have been the case earlier. The question remains how far west the continental air can get, and it looks overwhelmingly as if it will stay too far east this time around, but if the jet doesn't come crashing into Scandinavia there may be more favourable "windows of opportunity" further down the line.

[chionomaniac]

One of the areas that I will be looking at over the coming weeks will be the Oslo ensembles.

Here are the pressure ensembles. Here we see a very definite rise up to the 21st and then confusion. The operational is definitely below average.

So a return to zonal Scandinavian conditions certainly questionable.

[loadsa]

Seems to me that basically we are in for a northerly regime at the weekend, then next week we evolve into a westerly, then south westerly pattern (as per Ian Brown), but then at Christmas possibly back to square one, ie blocked Atlantic, and a north westerly pattern again.

Also as of lunch time today, there are NO warnings for snow from the Met Office for this week.

They have now

[legritter]

THANKS RADIATING DENDRITE . THANKSfor the info on CMC . i know the cold air is to our n/w , my grammar is sometimes poor .i was just saying that i prefer high scandi ,low channel , lets hope we can have plenty of this synoptic set up this winter . but of course with plenty of variation so that we can all see our dream frontal event . perhaps this winter we might get a good long beast from the east ,then north ,bring it on . some interesting possibilitys coming up on latest charts . cheers , i have not quoted youre post because im not sure what im doing plus computer naffed

[russ49]

the Met office have just issued this warning for snow for upto the Humber area so i think they are going for the more northern path or edging there bets lol

**just seen weather on BBC they say northern least likely :-)**

Yorkshire & Humber: severe weather warnings

<div class="highlight"> <p>You are currently viewing a non JavaScript (text only) version of this page. <a href="http://www.metoffice.gov.uk/about-us/help/website?detailid=2232">See our FAQ</a> for instructions on how to enable JavaScript.</p></div> Issued at - 14 Dec 2011, 12:35

Valid from - 16 Dec 2011, 00:05

Valid to - 16 Dec 2011, 10:00

Outbreaks of heavy rain will turn readily to snow during the early hours of Friday. The snow is likely to accumulate over time with a risk of up to 10 cm over higher ground. At low levels sleet is more likely but even here some lying snow cannot be ruled out.

The public should be aware that this could lead to travel disruption on Friday morning.

Edited December 14, 2011 by russ49

[Frosty.]

The canadian ensemble model, last run being the 00z really plays down the influence of high pressure next week and maintains a generally nw/se tilted jet and also produces a strong NW'ly blast around christmas time, it is chalk and cheese compared to the benign and relatively mild looking gfs charts for next week and beyond. The latest meto indicates a north south split with increasing risk of frost and fog as next week progresses for southern britain but remaining chilly and unsettled in the north with further hill snow and the longer range outlook has not changed.

Edit: potentially a major snow event for the midlands and towards the southeast on friday morning with heavy snow and high winds, the snow will not melt through the weekend as it looks like being a cold end to the week with further wintry showers around the coasts, especially the east coast with blizzards across northern scotland during the weekend in strong NNWly winds.

Edited December 14, 2011 by Polar_ Low

[georgiedre]

The canadian ensemble model, last run being the 00z really plays down the influence of high pressure next week and maintains a generally nw/se tilted jet and also produces a strong NW'ly blast around christmas time, it is chalk and cheese compared to the benign and relatively mild looking gfs charts for next week and beyond. The latest meto indicates a north south split with increasing risk of frost and fog as next week progresses for southern britain but remaining chilly and unsettled in the north with further hill snow and the longer range outlook has not changed.

Edit: potentially a major snow event for the midlands and towards the southeast on friday morning with heavy snow and high winds, the snow will not melt through the weekend as it looks like being a cold end to the week with further wintry showers around the coasts, especially the east coast with blizzards across northern scotland during the weekend in strong NNWly winds.

wont it be the west coast that gets a lot of showers! well on a n / nw wind????

[Frosty.]

wont it be the west coast that gets a lot of showers! well on a n / nw wind????

All areas exposed to a strong NNW'ly flow will get heavy snow showers so yes, western scotland, nw scotland, northern and northeast scotland and western plus n.isles should have a wintry weekend with snow showers and strong winds but winds dropping later as a ridge pushes in from the west but all of the uk look cold this weekend in a polar airflow and snow showers should also affect n.ireland and northern and eastern england but mainly coastal areas I think, the arctic air looks like reaching the far north of scotland later friday with snow showers arriving from the north.

Edited December 14, 2011 by Polar_ Low

[georgiedre]

All areas exposed to a strong NNW'ly flow will get heavy snow showers so yes, western scotland, nw scotland, northern and northeast scotland and western plus n.isles should have a wintry weekend with snow showers and strong winds but winds dropping later as a ridge pushes in from the west but all of the uk look cold this weekend in a polar airflow and snow showers should also affect n.ireland and northern and eastern england but mainly coastal areas I think, the arctic air looks like reaching the far north of scotland later friday with snow showers arriving from the north.

thanks p l

hope we all get snow! some of the models show heavy snow for my area on thursday night/friday morning! hope it happens.......good luck to everyone..happy model watching.

[stewfox]

Edit: potentially a major snow event for the midlands and towards the southeast on friday morning with heavy snow and high winds, the snow will not melt through the weekend as it looks like being a cold end to the week with further wintry showers around the coasts, especially the east coast with blizzards across northern scotland during the weekend in strong NNWly winds.

At 11.01 you posted it was all mild and pathetic an hour later a snow fest with lying snow for a few days !.

Make you mind up , you keep swinging from one extreme to another.

The positioning of the low should become more clear in tonights models then we will have a better idea on back edge snow/sleet/rain

[Frosty.]

thanks p l hope we all get snow! some of the models show heavy snow for my area on thursday night/friday morning! hope it happens.......good luck to everyone..happy model watching.

I forgot to mention wales but with a flow slightly west of north there would be snow showers there too, I really do think that once the low on friday moves away, arctic air will flood south but of course all the interest is now focused on friday morning as there now looks like being a lot of disruption but i'm unsure whether that will affect london/heathrow..will they get a chance to use their multi million £ of new equipment! i HOPE SO.

At 11.01 you posted it was all mild and pathetic an hour later a snow fest with lying snow for a few days !. Make you mind up , you keep swinging from one extreme to another. The positioning of the low should become more clear in tonights models then we will have a better idea on back edge snow/sleet/rain

YES because that is what the gfs and ecm is showing for next week! but I also posted a wee while ago about the canadian ensemble model being cooler about the mild boring muck affecting the uk next week so it's not sorted yet.

And please don't misquote me stewfox, I never said it would be a mild weekend, I was talking about next week becoming milder according to most of the model output so far today.

Edited December 14, 2011 by Polar_ Low

[Costa Del Fal]

GFS predicting an excellent wind direction for the Cheshire Gap streamer at times for most of Friday and Saturday. Pretty much perfect and the advantage of having the low to the South than over Scotland is that the winds are for at least for a time likely to be in a pretty much perfect position. Could still change, but much better prospects of this streamer than last weekend.

[Jhonny Peter Carson]

The Met while I appreciate are doing there best are leaving it a bit late are they not? I mean this is tommorow now not 120 plus hours out. Warnings for snow but then it is hedged as only falling as sleet on lower levels.

All the severe wind indications are gone now?

I am not sure this low is going to work as well as what they thought. I do not think that we will have the heavy snow and storm winds and if we do the Met are in a pickle as it will be so sudden that it will then be stated that 12 hour warning is still poor forecasting.

Excuse my downgrading drone, perhaps I need that snow fix. If I get one I will be telling everyone I predicted it first, lol.

14.35 at Newbury now. Sucker for this prediction malarkey. lol

[Frosty.]

The Met while I appreciate are doing there best are leaving it a bit late are they not? I mean this is tommorow now not 120 plus hours out. Warnings for snow but then it is hedged as only falling as sleet on lower levels. All the severe wind indications are gone now? I am not sure this low is going to work as well as what they thought. I do not think that we will have the heavy snow and storm winds and if we do the Met are in a pickle as it will be so sudden that it will then be stated that 12 hour warning is still poor forecasting. Excuse my downgrading drone, perhaps I need that snow fix. If I get one I will be telling everyone I predicted it first, lol. 14.35 at Newbury now. Sucker for this prediction malarkey. lol

Yes it's funny how the stormy/hurricane force warnings earlier this week have now been replaced by blizzard warnings, much better for all snow lovers and about time we had some snow!

[lorenzo]

Linking in this post from the Atlantic Storms thread as it is entirely model related. Good find Mapantz.

Met Office Cheif forecaster seeing more consensus in the models and moving this into an Ice and snow event, I think they are being pretty definitive now.

http://forum.netweather.tv/topic/71898-atlantic-storms-13th-december-2011-onwards-part-3/page__view__findpost__p__2185079

[johnholmes]

In theory yes but the showers are likely to be of rain, the Irish Sea is anomalously warm. Even the higher parts of Cumbria have seen principally rain and sleet during this cool zonal spell.

you obviously did not watch the news today Ian. One clip showing the mountain rescue weather check done daily, this one from Keswick and taking in some of the higher fells but snow appeared, 1-3cm I would estimate at fairly low levels. I have to admit I did not recognise any of the views on the lower fells but he was on his way up Hellvelyn, so perhaps 1000ft for the lower shots?

so your post is incorrect and perhaps a look at the Fell web cams would also show you are not correct.

Come on Ian how about some objective posting gawd alone knows what some of the necomers must think to the wide variety of options they are given on this thread.

again sorry admin and mods I know its not model discussion but it really is time some factual and objective comments were made in this thread.

one link to show how wrong/biased you are Ian

http://www.lakedistr...e.co.uk/gallery

current forecast re rain and snow

How Wet?

Snow showers; risk lightning

Squally snow and hail showers, and perhaps for an hour or so, the showers in some areas merging to give almost constant snow, giving whiteout. Rain below about 250m. Small risk thunder.

sorry I'll stop now

Edited December 14, 2011 by johnholmes

[Thundery wintry showers]

My reading of the forecast models points to a wintry mix of showers on low ground across the Cheshire Gap, Wales and into parts of SW England, with snow on high ground (say above about 100m in NW England, and 200-300m in SW England). Since a significant proportion of Wales and SW England is relatively high up, this points to significant wintry potential for a number of people in those areas, though some at low levels may well just see rain.

There is also potential for sleet and snow showers across NE England and East Anglia, depending on whether or not the winds veer northerly at some stage.

[rich1]

http://www.wetterzen..._London_ens.png

the op run is a bit dump but there is a degree of scatter after the 19th with a couple of tempting outliers

though a calm and mildish spell of weather for at least a couple of days is a possibility, so is a continued cold zonal pattern, or perhaps a anticyclone plopped over the uk. Easterly scenario the outsider but not impossible

xmas still over 10 days away. My guess is for either coolish HP [being optimistic that it wont be too far south] or cool zonal weather. But still far enough out to not be nailed on for anything

this present spell of weather wouldnt be too bad for an xmas pattern if it was to repeat itself, particularly further north, all things considered, with the weekend temperatures pretty cold everywhere. Not bad for an atlantic dominated pattern when several on here [naming no names] were expecting double figure days and nights. What is also worth bearing in mind is although the models do seem keen on the southern HP systems ridging north in to france/europe, they have been showing this on many runs for much of the month but thus far its been at best transient leaving us with cool-cold NW airstreams with only brief milder incursions for much of the month

Edited December 14, 2011 by rich1