Model Output Discussion - 5th December - 11th December

[sn0wman]

does it have to be in capitals?

Still time for the track and depth to change but

not only are the Northern isles going to get, even for them, some very high wind values as the winds veer into the NW, I suppose possibly in excess of 90mph but the Forth-Clyde valley? Its very finely balanced as to when the flow goes through the valley and linked into what temperature values are shown in the bottom 2-

3000ft but it might be very serious for that area. One I'm sure UK Met are watching closely along with all the already mentioned pssible areas of concern.

Does this include the Stirling area?

Thanks.

[johnholmes]

Hi John,

Although i don't post very often i do read the forum on a daily basis and enjoy reading your posts, very informative. Being on the coast in East Lothian we are used to getting some high winds, the worst i can remember being in December 1998 when they peaked at over 100mph and ripped some structures down and tore roofs of buildings. Could we be looking at similar strengths in my neck of the woods on Thursday evening/night into Friday? Could you explain what you meant with your reference to the temperature values that are shown in the bottom 2-3000ft?

Thanks

hi

Had to look up Preston Pans but yes it could be although you might just get a bit of shelter, the direction would be critical. The temperature bit might offset what I've just said. If there is an increase in temperature with height, up to about 3,000ft, it can cause the wind speed to 'funnel' between the surface and the inversion the temperature structure causes at 3000ft, thus increasing the actual wind speed at the surface. Hope thatis explained clearly enough-ask again.

Similar to snowman, again not totally sure of your exact position re the Forth-Clyde valley.

[legritter]

WELL I WOULD BANK ANYTHING SHOWING TONIGHT , I THINK THIS THREAD COULD BE IN TOTAL MELT DOWN COME THURSDAY .WEVE DONE OUR SHOPPING , PLENTY OF CANDLES AND FIREWOOD READY , WHO WOULD HAVE THOUGHT THIS 336 HRS AGO ,IF YOU COME BACK EURO S, WE WILL SEND OUR ATLANTIC BULLY BOYS AFTER YOU .STILL WAITING FOR UPDATED FAX ,COULD NEXT WEEKS LOW DIVE S/E STAY TUNED .,CHEERS LEGRITTER :smilz38: BUT DONT FORGET PAST LETDOWNS

[Mark Neal.]

18z has bumped this a little further north, looks really worrying for Scotland. Looks like Ireland away from the north coast may escape on this run. System goes from a 990mb low to a 960mb deepening low in just 12 hours. Amazing Oh dear. Western Scotland gets battered. Huge seas down the north Irish channel. Widespread damage.

Its also worth noting that we are now only 48 hours from the potential storm, Its getting nearer and nearer. Gfs does tend to overdo the power of low pressure systems though, but i have got a weird feeling its gonna be correct for once! We will soon find out, hopefully it won't be as serious as some of the models are making it out to be.

Edited December 6, 2011 by Mark Neal Ballooning

[sn0wman]

hi

Had to look up Preston Pans but yes it could be although you might just get a bit of shelter, the direction would be critical. The temperature bit might offset what I've just said. If there is an increase in temperature with height, up to about 3,000ft, it can cause the wind speed to 'funnel' between the surface and the inversion the temperature structure causes at 3000ft, thus

increasing the actual wind speed at the surface. Hope thatis explained clearly enough-ask again.

Similar to snowman, again not totally sure of your exact position re the Forth-Clyde valley.

Thanks John!

[Eskimo]

WELL I WOULD BANK ANYTHING SHOWING TONIGHT , I THINK THIS THREAD COULD BE IN TOTAL MELT DOWN COME THURSDAY .WEVE DONE OUR SHOPPING , PLENTY OF CANDLES AND FIREWOOD READY , WHO WOULD HAVE THOUGHT THIS 336 HRS AGO ,IF YOU COME BACK EURO S, WE WILL SEND OUR ATLANTIC BULLY BOYS AFTER YOU .STILL WAITING FOR UPDATED FAX ,COULD NEXT WEEKS LOW DIVE S/E STAY TUNED .,CHEERS LEGRITTER :smilz38: BUT DONT FORGET PAST LETDOWNS

Are you a game show presenter? :winky:

[EastLothianSnow]

hi

Had to look up Preston Pans but yes it could be although you might just get a bit of shelter, the direction would be critical. The temperature bit might offset what I've just said. If there is an increase in temperature with height, up to about 3,000ft, it can cause the wind speed to 'funnel' between the surface and the inversion the temperature structure causes at 3000ft, thus increasing the actual wind speed at the surface. Hope thatis explained clearly enough-ask again.

Similar to snowman, again not totally sure of your exact position re the Forth-Clyde valley.

Thanks for that John. Too be honest whenever these storms appear we do usually get some really strong gusts here, my thinking was that with the winds coming from the NW rather than W/SW as they normally do in these storms we may actually be hit a bit worse than usual with lack of shelter from that direction with the winds coming right down the forth and into my area?

[Mark Neal.]

Are you a game show presenter? :winky:

It sounds like he is lol, anyway the 18z is a much better run in my eyes, but its the Pub run, we can't take anything too seriously unless its before 3/4days time, i would say thats where FI is?!

Edited December 6, 2011 by Mark Neal Ballooning

[Daniel Miller]

It sounds like he is lol, anyway the 18z is a much better run in my eyes, but its the Pub run, we can't take anything too seriously unless its before 3/4days time, i would say thats where FI is?!

Well seeing as it kicks off on Thursday that's only less than 2 days time! It' pretty much nailed on!!!

[Mark Neal.]

Well seeing as it kicks off on Thursday that's only less than 2 days time! It' pretty much nailed on!!!

Yes i agree, the storm that is forecasted to begin on Thursday is pretty much nailed on. It's just a case of will see upgrades or downgrades, little tiny details will be added in the coming 24hrs im sure(Sorry if i always state the obvious!)

[snowlover2009]

Good grief that is one heck of a nasty low. Manchester north would be battered like hell. Although I do love storms, what an interesting month so far. Its unbelievable, gfs 2/3 days ago showed a ridge building from the south this week and now we have this very deep depression which is a beast.

[legritter]

I WILL CUT DOWN ON MY capitals ,their you are , i keep forgetting caps lock ,it will all come with time . im off to bed , iwill look in morning for fax , computer keeps running out of memory ,regards .

[Daniel Miller]

Yes i agree, the storm that is forecasted to begin on Thursday is pretty much nailed on. It's just a case of will see upgrades or downgrades, little tiny details will be added in the coming 24hrs im sure(Sorry if i always state the obvious!)

Yes I see what you mean. Obviously we're all hoping for upgrades, temperature wise, not wind speed! ahha

Little things are bound to change but... If things continue in the same vein we could have an even better situation than now, marginally:) (Fingers crossed!)

[Mark Neal.]

Good grief that is one heck of a nasty low. Manchester north would be battered like hell. Although I do love storms, what an interesting month so far. Its unbelievable, gfs 2/3 days ago showed a ridge building from the south this week and now we have this very deep depression which is a beast.

It just proves that the models are being so inconsistent. It looked pretty good money on high pressure returning for us upto only a few days ago, now it is much cooler zonal pattern in the offering.

[kold weather]

Models certainly still Atlantic dominated, looks like they are hinting at another attempt at a cold zonal shot this time next week, the ECM doesn't quite make it but the GFS does...will remain to be seen.

The big story however is that exceptional low...the NAE and GFS both suggests mean speeds getting into the 60-70kts range, gusts would probably locally go upto 90-100kts and that would cause in places extreme damage. Really can't overstate this storm enough at the moment, it looks dangerous.

[Nick F]

Another deep low (955mb) headed for Scotland early Tues still showing on 18z GFS, 12z ECM has it too. Batten down the hatches!

The Atlantic low pressure machine seems relentless into deep FI, a good few days yet maybe until we see the low heights/cold uppers to the north, that drive the strong zonal flow, finally fragment.

[A Winter's Tale]

Although the winds here are set to be scary, I'd like to know what's going to happen in terms of snow between Thursday Night and Friday afternoon. I'm just wondering how much the back end of the low and NWly following would deliver and where? Thanks.

[Cecil Hogmanay Melchett]

Another deep low (955mb) headed for Scotland early Tues still showing on 18z GFS, 12z ECM has it too. Batten down the hatches!

The Atlantic low pressure machine seems relentless into deep FI, a good few days yet maybe until we see the low heights/cold uppers to the north, that drive the strong zonal flow, finally fragment.

Yes i think the strong vortex clashing with the warmer atlantic is helping brew some major lows.

one things for sure we can forget all about northern blocks for quite some time!!

[SMU]

Morning All-

One of the most outrageous GFS runs that I have ever seen this morning with the UK getting BATTERED by 2 lows - one in the north then one further south highlighted here-

http://176.31.229.228/modeles/gfs/run/gfsnh-0-42.png?0

& then Ireland gets wiped out-

http://176.31.229.228/modeles/gfs/run/gfsnh-0-150.png?0

not only extreme damaging winds but every type of weather thrown in- with snow more of a feature again in Scotland-

Interesting is the UKMO at T60 has the -10c isotherm hitting Scotland for the first time this year- not bad in a North westerly-

http://www.meteociel.fr/ukmo/run/UW60-7.GIF?07-05

maybe the most intersesting Chart of the night is the UKMO t72- which shows a small wedge of the -10c isotherm all the way down to the SE/East coast-

http://www.meteociel.fr/ukmo/run/UW72-7.GIF?07-05

even -9c for london- thats going to feel RAW

http://www.meteociel.fr/ukmo/run/U72-7.GIF?07-05

All in all a stormy week, definatley no trough disruption as id hoped to see & fair play to those that called it-

the one real significant thing is that the jet seems to be forecast to track further & further south ( usually because the polar cell is expanding into Winter) this may well mean that the areas like the midlands & wales could come into the snowy fray from small shortwave clippers that scoot through in the flow...

stay safe

regards

Steve

[snow drift]

Thanks Steve for a very informative post.

It should be recognised that you help many of us learn from your posts and if you have called it one way and it looks to go another, you are the first to point this out.

How anyone can call the current output as a "Bore fest" is beyond me. There is so much going on. Lows hammering in to the UK. Potentially damaging winds. Different parts of the UK taking the brunt (North predominately), cold air being shown to make it quite south at times. Snow a strong possibility for favoured areas.

This I find fascinating.

Agreed it’s not showing deep cold for all but that does not equate to "bore fest" in my book.

[Weather-history]

the one real significant thing is that the jet seems to be forecast to track further & further south ( usually because the polar cell is expanding into Winter) this may well mean that the areas like the midlands & wales could come into the snowy fray from small shortwave clippers that scoot through in the flow...

Steve Murr's opinion

A very stormy and progresive outlook this morning, with a very brief Nwerley on Friday soon replaced by the next Atlantic system. Going forward we see the pressure rise to the South that I was talking about last night in repsonse to the persistant and burgeoning PV.

Ian Brown's opinion

They both can't be right,

[winterof79]

A quite acceptable start to winter from my perspective,no false dawns very 70s/80s dare i say.Nice potent shot from the north and then more cool/cold zonal.I will call 144z as far as is worth looking at with such a volatile set up.No mild showing,all in all very traditional.Pessure seems quite stable to the south from what i can see up to 144z maybe down 5mb.

Edited December 7, 2011 by winterof79

[carinthian]

Another deep low (955mb) headed for Scotland early Tues still showing on 18z GFS, 12z ECM has it too. Batten down the hatches!

The Atlantic low pressure machine seems relentless into deep FI, a good few days yet maybe until we see the low heights/cold uppers to the north, that drive the strong zonal flow, finally fragment.

Yes Nick, an interesting period of weather in your latitudes. As JH mentioned yesterday the temperature differential between Newfoundland and the Greenland Glacier is very pronounced at the moment and ripe for the feeding ground for some intense weather systems. Probabaly at least 5 days active weather with the Polar front waving south at times in the strong zonal flow you mention. Beyond that ? a final fragment would seem to be some days off as yet. Meanwhile we remain snowless in The Austrian Alps with with frontal activity across Northern Europe having little impact at the moment. A real worry .now!

C

[Frosty.]

Steve Murr's opinion Ian Brown's opinion They both can't be right,

polarised opinions, poles apart and I hope that shortwave clippers becomes the new buzz words in the next few weeks. The models show another very stormy spell on our doorstep for tomorrow/friday with chance of blizzards for some parts of the uk on friday once the screaming NW'ly arctic blast arrives and with the jet tending to dig further south, cold incursions are likely to dominate rather than mild zonal.

Edited December 7, 2011 by Polar_ Low

[nick sussex]

Good agreement on that storm due to hit tomorrow afternoon and still the NAE progs some very worrying wind speeds for western Scotland:

http://www.weatheron...V=0&WMO==

This is also a worry for areas further east towards Edinburgh with the wind funneling through the Clyde Valley, I hope my geography is right!

Also Northern Ireland especially northern counties could be badly effected.

The storm deepens rapidly to the west of Ireland between 24 and 36hrs, its hard to believe that the origins of this nasty low starts off as a weak shortwave heading off the eastern USA.

After this low it still looks very unsettled with no sign yet of a change.

Edited December 7, 2011 by nick sussex