Scotland - Regional Discussion

[lorenzo]

Good find LSS, they look pretty identical to me. Further depth in the cold pooling on the 1884 chart, but nonetheless incredibly similar.

[LomondSnowstorm]

Does it really matter? Hard call for me but is it the 06z?

It was a bit of a rhetorical question. They look fairly similar to me, though pressure never quite reaches 926mb on the 6Z.

[blitzen]

It was a bit of a rhetorical question. They look fairly similar to me, though pressure never quite reaches 926mb on the 6Z.

I am hopeless at reading charts LS! I also find the model thread quite confusing. Some are taking winds further north and some say it will still be the south? (Friday) What's your take on things at the moment?

[A Winter's Tale]

A very scary storm for next week. I do wonder how the met office and scotiish government will react and would there be more schools open next time because of an "oh it wasn't that bad" attitude.

I'm also quite interested in the northerly toppler following the storm. Hopefully we can all get something out of it (tha's if it actually happens). I do believe that there will be another two or three storms after next week as the Atlantic is looking very active. However, on the otherhand, I wouldn't be surprised to see a few more snow oppurtunites from polar maritime air as I do believe that the positioning of lows may well be a bit further south come the end of the month.

[BleakMidwinter]

What's your take on things at the moment?

Stay hiding under the bed from Thursday til saturday....

[Stuart Allan]

How bad do you guys think the central belt will be hit by both this weeks storms? thanks Stu in East Kilbride

[Stormeh]

How bad do you guys think the central belt will be hit by both this weeks storms? thanks Stu in East Kilbride

It all depends on the track of the storm, we won't know the exact track until nearer the time but it could be bad as last Thursdays storm if it comes off.

[LomondSnowstorm]

I am hopeless at reading charts LS! I also find the model thread quite confusing. Some are taking winds further north and some say it will still be the south? (Friday) What's your take on things at the moment?

I'm going to try and use the John Holmes technique of looking at like for like runs with the GFS:

00Z: The low is progged to hit 15 hours earlier than yesterday's 00Z and centred over the borders instead of the Minch. It's also slightly less intense:

http://hw.nwstatic.co.uk/gfsimages/gfs.20111210/00/159/h500slp.png

http://hw.nwstatic.co.uk/gfsimages/gfs.20111211/00/120/h500slp.png

06Z: The low hits three hours earlier today than yesterday and is centred very slightly further south. Something of a middle ground scenario between yesterday's 00Zs with the storm hitting in the early hours rather than Thursday evening or Friday afternoon, though today's run shows the low as being very intense:

http://hw.nwstatic.co.uk/gfsimages/gfs.20111210/06/144/h500slp.png

http://hw.nwstatic.co.uk/gfsimages/gfs.20111211/06/117/h500slp.png

12Z:

The main low hits around 9am on Friday and is further north than on any other run. Probably the windiest scenario for Scotland:

http://hw.nwstatic.co.uk/gfsimages/gfs.20111210/12/141/h500slp.png

The 18Z placed the low further south again like today's 00Z and again arrives earlier than most other runs:

http://hw.nwstatic.co.uk/gfsimages/gfs.20111210/18/126/h500slp.png

ECM 00Z:

The low looks to hit again in the early hours of Friday with winds most intense on the western side of the low

http://hw.nwstatic.co.uk/ecmimages/20111211/00/ecm500.120.png

Perhaps not as intense and further south, so the damage would be concentrated further south.

ECM 12Z: This one was further north too http://hw.nwstatic.co.uk/ecmimages/20111210/12/ecm500.144.png

UKMO 12Z:This was the furthest south of the 12Zs yesterday, putting it around the Borders

http://www.meteociel.fr/ukmo/archives/2011121012/UW144-21.GIF

UKMO 00Zs:

The worst of the damage on yesterday's run was for the north of England

http://www.meteociel.fr/ukmo/archives/2011121000/UW144-21.GIF

and today the risk has shifted further north http://www.meteociel.fr/ukmo/archives/2011121100/UW120-21.GIF

In summary, no real trend regarding the position and timing of the low. It will most likely hit around the early hours of Friday though more likely to be earlier than later I reckon. Somewhere is likely to get hit very badly, and at the moment, judging by the ensembles (http://176.31.229.228/modeles/gens/run/gens-21-1-114.png?6 ) and all the other evidence, it will most likely be the north of England. However, slight shifts in the positioning and intensity will change a lot. The main areas to watch will be the central belt, the Borders, around the Irish Sea, the Northwest of Ireland, the Hebrides and perhaps Aberdeenshire down the east coast if it intensifies while passing over us.

[Stormeh]

Good post, thanks LS.

[LomondSnowstorm]

How bad do you guys think the central belt will be hit by both this weeks storms? thanks Stu in East Kilbride

The first storm definitely won't be as bad as Thursday. Gales certainly and the worst of the winds will be around central Scotland but gust speeds around 20mph short of what they were on Thursday.

[snowmess]

A very scary storm for next week. I do wonder how the met office and scotiish government will react and would there be more schools open next time because of an "oh it wasn't that bad" attitude

You make a good point here - I wouldn't be too surprised if the Scottish Government decide to keep schools etc. open as a reaction to last weeks storm not being 'too bad'.

I guess we'll just need to wait and see, hoping that the storm isn't as bad as it is expected

[glasgow-guy]

You make a good point here - I wouldn't be too surprised if the Scottish Government decide to keep schools etc. open as a reaction to last weeks storm not being 'too bad'.

I guess we'll just need to wait and see, hoping that the storm isn't as bad as it is expected

TBH i see the potential for a repeat of hurricane bawbag in Scotland but this time with England taking the brunt of the worst winds don't get me wrong last

Monday was awful but we mostly survived un scathed England this time may not be so lucky

Edited December 11, 2011 by glasgow-guy

[lorenzo]

For the newer folks always keep an eye here http://www.metoffice.gov.uk/weather/uk/uk_forecast_warnings.html

Yellow alerts currently in place for both systems.

[A Winter's Tale]

I'm going to try and use the John Holmes technique of looking at like for like runs with the GFS:

00Z: The low is progged to hit 15 hours earlier than yesterday's 00Z and centred over the borders instead of the Minch. It's also slightly less intense:

http://hw.nwstatic.c...159/h500slp.png

http://hw.nwstatic.c...120/h500slp.png

06Z: The low hits three hours earlier today than yesterday and is centred very slightly further south. Something of a middle ground scenario between yesterday's 00Zs with the storm hitting in the early hours rather than Thursday evening or Friday afternoon, though today's run shows the low as being very intense:

http://hw.nwstatic.c...144/h500slp.png

http://hw.nwstatic.c...117/h500slp.png

12Z:

The main low hits around 9am on Friday and is further north than on any other run. Probably the windiest scenario for Scotland:

http://hw.nwstatic.c...141/h500slp.png

The 18Z placed the low further south again like today's 00Z and again arrives earlier than most other runs:

http://hw.nwstatic.c...126/h500slp.png

ECM 00Z:

The low looks to hit again in the early hours of Friday with winds most intense on the western side of the low

http://hw.nwstatic.c.../ecm500.120.png

Perhaps not as intense and further south, so the damage would be concentrated further south.

ECM 12Z: This one was further north too http://hw.nwstatic.c.../ecm500.144.png

UKMO 12Z:This was the furthest south of the 12Zs yesterday, putting it around the Borders

http://www.meteociel...12/UW144-21.GIF

UKMO 00Zs:

The worst of the damage on yesterday's run was for the north of England

http://www.meteociel...00/UW144-21.GIF

and today the risk has shifted further north http://www.meteociel...00/UW120-21.GIF

In summary, no real trend regarding the position and timing of the low. It will most likely hit around the early hours of Friday though more likely to be earlier than later I reckon. Somewhere is likely to get hit very badly, and at the moment, judging by the ensembles (http://176.31.229.22...-21-1-114.png?6 ) and all the other evidence, it will most likely be the north of England. However, slight shifts in the positioning and intensity will change a lot. The main areas to watch will be the central belt, the Borders, around the Irish Sea, the Northwest of Ireland, the Hebrides and perhaps Aberdeenshire down the east coast if it intensifies while passing over us.

Wow! I'll give you a Gold Star for that.

[Stuart Allan]

Just posted a couple of hours ago by STV http://news.stv.tv/scotland/286958-scottish-storms-return/

[blitzen]

Thanks very much for your very detailed post LS - much appreciated. With all the variations, it's very difficult to make an accurate assessment on where will be worst affected. I should have known better and stuck to the same set of models each day (God knows I've been told enough times!)

[Ruzzi]

What's people's thoughts on the snow potential for tuesday? I have to say I never really noticed to snow potential due to constantly monitoring the approaching storms however there does seem to be a window of opportunity for some snow. TWO for example has my location receiving snow for most of the day with about 4 inches falling. Also NW shows the potential for snow with these snow risk charts:

Note how central and southern Scotland, as well as north west England are within the 524 DAM.

Max temps also show the potential for snow.

And finally the precipitation rate for noon on tuesday show that western Scotland could receive some decent snow (i.e more than a dusting)

One last thing, The dew point is also at 0C or below for most of the mainland UK on tuesday.

People's thoughts please???

[lorenzo]

It is going to be extremely tricky picking out the distribution of snowfall within the next 48-60 hrs, simply too many things to factor in.

The only trend i can see is the familiar snowfall map as viewable on many forecasts for the west of the country.

The NAE gives us as snowier start to the week, GFS kicks off with more sleety conditions.

By Tuesday 12:00 the NAE model leaves us at an incoming cliffhanger , of course propelled along by some fierce wind profiles, again GFS keen on a warmer solution and more of the wet stuff.

Reviewing what happened on Thursday and the models projected a quick draw down of colder air that was meant to send something of a snowfest, this turned out to be a completely different picture.

Overall nigh on impossible to guess the depth of cold following this system or how the upper air will modify, the charts give us hints but think it will be down to Nowcasting at the time.

[Hairy Celt]

What's people's thoughts on the snow potential for tuesday? People's thoughts please???

My quick answer would be don't bank on it as there'll be too much warm air wrapped up in that low. There may be spells of snow but just as likely is sleet, hail, rain and dirty smeggy bits from England. Not nice. MWIS is hedging its bets: 'rain low slopes' for Tuesday, 'rain below 600m' on Weds.

[LomondSnowstorm]

My quick answer would be don't bank on it as there'll be too much warm air wrapped up in that low. There may be spells of snow but just as likely is sleet, hail, rain and dirty smeggy bits from England. Not nice. MWIS is hedging its bets: 'rain low slopes' for Tuesday, 'rain below 600m' on Weds.

I think the centre of the low is far enough north that we could end up in a decent cold sector (although for your location northwards that might well be the case). Currently uppers are progged at around -4/-5 for central and southern Scotland so for areas sheltered from westerly maritime influence that might well be enough. Not saying it'll be widespread and severe but there is that kind of potential.

[A Winter's Tale]

I'm not really going to get all that interested in Tuesday's potential snowfall as the models and forecasts seem to suggest nothing of any particular interest. However, I would love it if there was snow.

[penicuikblizz]

Light snow falling in Penicuik!!

[A Winter's Tale]

Light snow falling in Penicuik!!

You're kidding me!

[penicuikblizz]

Snow getting heavier now, was not expecting this, it was raining about a hour ago

[lorenzo]

Interesting 12z from ECM tracks the first of this weeks storms on a more SE-NW path.

Here at 48 and 72 hours the incoming path is North of Ireland then follows on this trajectory.

ECM also calms down the Friday storm somewhat, slightly different from the GFS, and leaves us with colder uppers.

UKMO places the low at around 955mb

Looking forward to having a look at this evenings Fax Charts to see the human intervention on the track of the first low, colder systems than first thought??