Model Output Discussion - 30th November onwards

[East_England_Stormchaser91]

Yup. Aside from snow in N/NE & strong winds in some areas, it's a coastal flooding threat that grabs our attention at that juncture in the output timeline.

Is it spring tides around then Fergie? That has got me concerned now, as I am around the flat fens area! Would not take much to flood a lot of the flat land around here   !!!

[Purga]

Fax goes with raw ukmo output.

The London extended chillier than I expected having viewed the Dutch. Perhaps we will be cloudier and cooler by day under any MLB.

And hopeless for any snow I'm afraid.

[SE Blizzards]

Pert 12 please 

 

http://www.meteociel.fr/modeles/gefs_cartes.php?code=12&ech=300&mode=0&carte=0

[fergieweather]

Is it spring tides around then Fergie? That has got me concerned now, as I am around the flat fens area! Would not take much to flood a lot of the flat land around here !!!

Yes Fri AM. Some real concerns being expressed and very much focus of attention. Note how a few EC members also run polar low south at same time off W Norway and exacerbate issue if reality as this critical to high wind potential. Shades of '53 re set-up. Expect more on this tomorrow am. Edited December 1, 2013 by fergieweather

[abruzzi spur]

Yes Fri AM. Some real concerns being expressed and very much focus of attention. Note how a few EC members also run polar low south at same time off W Norway and exacerbate issue if reality as this critical to high wind potential. Shades of '53 re set-up. Expect more on this tomorrow am.

My goodness.  That '53 flooding was awful, terrible loss of life as well as devastating impact on property.  Let's hope it's not even a vague echo of that.....

 

AS

[Catacol]

Whatever happens next weekend, the longer term prospects for cold are looking as poor as they can be with continuous charts like this at this sort of timeframe :

 

 http://www.wetterzentrale.de/pics/Rtavn2401.png

 

Your link must be malfunctioning then - because it shows a potential battleground scenario between atlantic systems and a scandy block even with an intruding azores high. I dont believe this pattern will come to fruition - but "as poor as they can be?" Really?? C'mon Ian - why do you do this? Any newcomer looking at that chart and your response will be confused. Any old timer will take one look and ignore the comment. So why make it? "As poor as they can be" would be low pressures firing right through scandy with a strong euro block to the south.

 

The 850s that go with that chart are below. Hardly a blow torch.

 

Edited December 1, 2013 by Catacol_Highlander

[Blake]

Hopefully not posting this in the wrong thread, but just so people can keep an eye on it and how things develop over the coming few days, I found this relating to what Ian mentioned regarding 1953. With the potential gusts and sea level rises there is definitely concern over safety to residents and structures in low lying coastal regions.

 

 

 

This on 30th Jan...

 

...to this on 31st Jan....

 

 

...and this on the 1st Feb. Something for sure to keep an eye on!

 

[Dave Kightley]

Nice cold uppers on the UKMO this morning 144h has -8 covering the uk. -12 in Scotland

Edited December 1, 2013 by Dave Kightley

[Dave Kightley]

GFS alot further east and quicker moving the high east. Could easily be a Scandi high but instead a BBQ fest in the end.

 

So unrealistic to me to blow up the high covering the whole of Europe nearly that can't tell if a Scandi high or Euro  is the signal here. HAHA Could easily be either before stating the obvious.  

Edited December 1, 2013 by Dave Kightley

[chionomaniac]

Anyone looking at the UKMO this morning who remembers the debate about yesterdays 12Z will be intrigued to see that the UKMO has dropped the idea of the 75% of energy over the top. We now have a more uprighted  Atlantic trough and deeper cold down the UK as a result. 

 

 

 

 

[Dave Kightley]

 Great storm of 2013 on one side and a BBQ on the other. Who said British weather were boring hey . Complete waste of a run from the GEM, the difference between it and 12z is laughable at 144h

[Great Plum]

Northerly blast looks more and more certain now...

http://www.wetterzentrale.de/pics/Recm1201.gif

http://www.wetterzentrale.de/pics/Recm1202.gif

-5 line clears the south coast... -10 into Scotland...

The GFS (bless it!) is slowly agreeing on a short sharp cold blast too...

http://www.wetterzentrale.de/pics/MT8_London_ens.png

Edited December 1, 2013 by Great Plum

[Great Plum]

Saturday looks really cold with -10s clearing the south coast...

http://www.wetterzentrale.de/pics/Recm1442.gif

I'm not too good at this, but I think there's still some energy in the southern arm of the jet...

http://www.wetterzentrale.de/pics/Recm1441.gif

High over the country by Sunday but still bitterly cold...

http://www.wetterzentrale.de/pics/Recm1681.gif

http://www.wetterzentrale.de/pics/Recm1682.gif

Edited December 1, 2013 by Great Plum

[Polar Maritime]

Yes a much cleaner Northerly this morning.. -11 -12 850's into the the Midlands, And heavy snow showers over the Pennines and down to lower levels will make it feel bitter adding on the wind chill. Not a bad start to Winter ! 

 

[That ECM]

This mornings output agrees on a plunge of cold air. The small difference in the positioning of the high has such a big difference to what many would experience, in terms of precipitation. Ie would you get any? If so, what type? How strong would the wind be? How long would it last?

This is fascinating and still much to be resolved. Will we get a correction west? Will we get a correction east? Come Thursday there will be posts saying it's moved 50 miles this way or that and look at the impact. The fax charts will be the tool to use from here on in I feel.

If you are able to put aside the emotion of its better or worse as things develop, this is a great time to learn. Love it. Oh and please move west a bit UKMO and GFS!!

Forgot to add, this toppling high, which has been toppling for a week or so is still sat over us in ten days time!!! Some topple that!!

Edited December 1, 2013 by That ECM

[TSNWK]

Yep ECM holding firm this morning with the northerly blast, afterwards the high drifts over the UK, however is there a bit of northward drift between 192 & 216' which is a postive I think for sustaining the cold.

Yep the 240 at 1st looks boring when looked in isolation with the high slap bang over the UK, however the high is not sinking but building back slightly north and heights are building to the north east to my untrained eye.

Could be far worse ways to kick of winter for coldies Zonal it is not.

Edited December 1, 2013 by TSNWK

[Great Plum]

Conjecture at this stage but FI on the ECM...

Monday:http://www.wetterzentrale.de/pics/Recm1921.gif

http://www.wetterzentrale.de/pics/Recm1922.gif

High pressure centered over southern England - warmer uppers but likely to remain cold for the majority...

Tuesday:

http://www.wetterzentrale.de/pics/Recm2161.gif

http://www.wetterzentrale.de/pics/Recm2162.gif

Bit of an ugly scene over Greenland but high pressure should keep it settled and cool despite warmer uppers... Hint of a Scandi high?

Wednesday:

http://www.wetterzentrale.de/pics/Recm2401.gif

This is not zonality! Notice there is still some energy in the southern arm and if anything, 'our high' has drifted northwards - it's not sinking!

Edited December 1, 2013 by Great Plum

[Frosty.]

A very strong Arctic Blast firming up now for thurs / fri / sat, could possibly last even longer than that, navgem 00z going for a longer blast eventually, gem 00z starting to come back aboard and ecm / ukmo 00z looking peachy. Lots of heavy, frequent snow showers flooding south during thursday, driven south on a strengthening Arctic airflow with troughs swinging south in the increasingly bitter flow with severe frosts and ice plus snow with drifting in the Northerly Gales, especially for exposed n & e areas where disruptive snow could occur, friday probably the peak with the most wintry conditions but continuing through saturday.........so although it's a benign start to December...it will become increasingly wild &  wintry during the second half of the week ahead.  

 

Arctic Express here we come

[bluearmy]

And hopeless for any snow I'm afraid.

Not sure anyone has mentioned snowfall post the northerly purga??

ECM has corrected east by about 200miles with the lw pattern over the past 24 hours. The other models, well, no point in commenting.

will be interesting to see if we now have the solution with the northerly or if th euros will correct a bit east.

The gefs are rock solid on a strong ridge in our locale stretching north towards Svalbard at T192. Thereafter, plenty of options. No indications so far that a scandi/sceuro block is not on the agenda.

[Iceberg]

The general N.hemi pattern looks to reset to me to the previous 2-3 period. I can't yet see any major pattern change towards cold. Their was a chance of it, but tbh its slipped by imho.

Generally good agreement now amongst the bigger models on things.

Re the Thursday/Friday/Satuday period. For me its looking like.

Thursday front moves into scotland giving largely snow, due to the heavily undercut cold air giving 5-10cm across central scotland 2-5cm for other areas. As thursday progresses it moves south down into northern england, again largely as snow, with sleet for the front and coastal areas. Generally 1-3cm, but upto 5cm in places on the highground.

The front then erodes quickly as it moves snow into thursday evening, giving a dusting for some 1-2cm at most.

As we move into Friday the showers are very restricted effecting N and NW Scotland, with shower activity through the Cheshire Gap into midlands down to birmingham largely of snow, giving 1-5cm, but more than 1cm really restricted.

All shower activity dies as we move into friday night and saturday with a very cold night friday night, cold bright saturday and cold saturday night.

 

Then settled, chilly nice december weather for awhile.

 

Its still along way off but i would be surprised if things were much different to the above and the above is really just to set expectations. 

[SLEETY]

yep good summary Frosty,lol.

 

As you mentioned the feature to look out for will be the sudden formation of polar lows later next week.The Northern Isles and.Northern Scotland in particular can suffer from  very severe conditions in these sort of setups,with huge drifts piling up in severe gale-force Northerly winds.

 

DECEMBER 1995

 

"During Xmas Eve night, a polar low approached northern Scotland and this gave the severest weather for the month.
There were severe blizzards and gales with drifting snow. The Shetlands was worst hit with depth of level snow at 35cm
and drifts well in excess of this. A state of emergency was declared on the Islands."
DECEMBER 1995

[Iceberg]

I could live to regret this, but there is No chance of  Polar Low under this set up. You don't have the fetch with the correct 500 temps and the 500 winds are not the correct angles.

I just want peeps to be realistic.

[Gibby]

Good morning. Sorry no report last night but too busy with work. However, here is today's account of how the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM look for today Sunday December 1st 2013.

 

All models show a large annticyclone close to Ireland with a gentle Northerly flow over the UK. A lot of cloud is trapped under this HIgh pressure and will continue to dominate conditions over most areas for the first few days of the week with limited brightness and just a little overnight frost and fog if skies happen to clear somewhat overnight. By midweek most models show High pressure weakening slowly and allowing a weak cold front to slip South on Wednesday with a little rain travelling North to South over all areas. This is then followed by another one on Thursday, this time more marked with a switch to cold and strong NNW winds with wintry showers travelling South all the way down to Southern England by Friday. Frosts would return at night and snow showers would be falling thick and fast across some Northern and Eastern areas at times with even a few possible in the South for a time. Through next weekend all models illustrate High pressure moving in close to the South of the UK with the Northerly flow becoming cut off with a legacy of cold air over the South with clear skies giving rise to sharp night frosts and freezing fog patches while the North becomes less cold as winds settle from the West with more cloud spilling in too.

 

GFS, in Week 2 shows High pressure moving away SE into Europe and allowing all areas become under the influence of an increasingly mild and strong SSW flow with Low pressure spiralling around in the Atlantic sending troughs towards the North and West with rain at times, though amounts in the East and SE would be small or non existent at times. At the very end of the run somewhat colder air may reach Southern and Eastern areas as a SE continental drift to the wind reaches these areas.

 

UKMO today closes it's run next Saturday showing High pressure over Western Ireland with a decreasing but still very cold straight Arctic Northerly flow over the UK delivering snow showers to Northern and Eastern coastal areas in particular, all the way down to Essex and Kent. The West would become largely dry but cold with sunny spells and overnight frosts.

 

GEM sinks High pressure away South from late next weekend and into the second week with a strong and less cold Westerly flow developing for all with rain at times too, chiefly but not exclusively in the North and West with average vlue temperatures by midweek.

 

NAVGEM holds High pressure over the UK with a centre much further NW towards Greenland with a ridge SE across the UK. The end of it's run would be typified by very cold and frosty weather with snow showers dying away from NE areas apart from the far NE coast. Some sunny days would probably compensate for the very cold conditions.

 

ECM today shows High pressure holding firm across Southern England having arrived here next Sunday. The North would slowly become less cold following the cold snap and a lot of cloud would encompass these areas off the Atlantic with little in the way of frost and fog then. These benign conditions will gradually extend South to Southern Britain too by the middle of Week 2 replacing the frost and fog patches of early in the week.

 

The GFS Ensembles shows good support this morning for a short cold snap late this week and coming weekend to be followed by a NW/SE split in the weather with a long fetch SW'ly looking the most likely option. All areas would be at risk of some rain at times, only a little at times in the SE but with some wetter conditions to the North and West along with strong winds and temperatures everywhere recovering to above average.

 

The Jet Stream shows the flow tilting to a more SE direction later this week down across the UK from it's current location which is well North of the UK. It then resets in a NE directions across the Atlantic and across Scotland through Week 2 indicating Low pressure to the NW and High pressure to the SE of Britain.

 

In Summary the weather is set to turn colder briefly at the end of this week and next weekend with some snow possible for a time in the North and East and sharp overnight frosts in the cold North wind. In the meantime the weather will stay cloudy and benign with dry weather until a couple of weak fronts deliver the cold snap soon after midweek. Then through Week 2 it's all about where the High killing off the cold North feed ends up. The Americans seem to want to sink it SE over Europe quite quickly next week setting up a changeable and relatively mild and breezy SW feed with rain at times, mostly in the North and West while ECM shows High pressure holding across the South with a return to benign and increasingly cloudy and less cold conditions following a frosty start to the week. Which is right? It's a case of more runs needed I'm afraid.

[bluearmy]

I could live to regret this, but there is No chance of  Polar Low under this set up. You don't have the fetch with the correct 500 temps and the 500 winds are not the correct angles.I just want peeps to be realistic.

I think Ian mentioned a few ECM ens members bring one down from just off the Norwegian coast. Of course, if it happens we get into the definition of the differences between a true polar low and a small depression coming down from arctic.

[Frosty.]

If there can be north sea storm surges there can be polar lows, depends how the strengthening arctic flow is aligned and how long it lasts, we know that showery troughs will swing south from the arctic because the fax chart on a previous page shows them..wait and see... :-)