Model Output Discussion - cold spell to end Autumn

[January Snowstorm]

All a bit fragile on the 18z 

Great to look at but years of experience tells me where it can go wrong....

One thing that's gaining momentum is very cold uppers directly to our North.....proper cold!

[Mucka]

JFF GFS pulls a frigid Easterly out of the hat in deep FI 

[Captain Shortwave]

Pretty happy with the GFS/UKMO this morning.

   

Both see that trough being sent south east with the ridge close to Iberia retrogressing and both would allow a northerly to develop, importantly this time we apear to have a much moreexpansive and potent cold pool to our north to tap into so even a toppler could deliver snow to low levels if we see this arctic outbreak next week.

[SMU]

^^^ this evolution very very similar to 9 March 2013 with the ridge being squeezed up NW with deep cold come round from the NE - blocking is just further west this time... A great month to be comparing with-

Awsome Easterly at the end of the GFS air all the way from Siberia!

[geordiekev]

10 minutes ago, Mucka said:

JFF GFS pulls a frigid Easterly out of the hat in deep FI 

From the view we had at the end of a barrel Yesterday, not too shabby really. On Sunday I did worry TBH as when there's little room for upgrades is only one way models will go, but held back not to pull this place down,  but I have to say I'm very encouraged and excited for the next few days and the following week. 

Everything after that is pie in sky stuff so to still be pulling off jolly good synoptic through to mid December is fab in my book.

Ofcourse there's still so many runs to contend with in just one day but better to start on a high as yesterday was plain cruel. 

Edited November 29, 2017 by geordiekev

[geordiekev]

Did I say I was excited for next few days, I should have looked outside, damn you models, your like Sirens 

Edited November 29, 2017 by geordiekev
luckily I brought the potted daffs in this year

[knocker]

 

The current synopsis is low pressure to the east centred on southern Norway and high pressure south of Iceland thus today a continuation of the cold northerly winds, perhaps a tad east of north with wintry showers mainly in the north and east . Elsewhere dry and sunny but cold everywhere with an icy start.

Much of the same tonight remaining windy with showers concentrated in the north and coastal areas and another cold night and icy tomorrow morning. During tomorrow a slight change of emphasis as the high pressure tends to ridge north east and the low south to Denmark thus veering the surface wind north east and onshore along the east coast. With the advent of a trough in the flow frequent showers, or longer periods of snow, are quite possible along the east coast down as far as East Anglia and even down to the south east later on.

By Friday midday the low has slipped south west and just about lost it's identity with the last of the precipitation clearing the south east as the ridge slips south over the UK cutting off the cold northerly flow and raising the temps to near average. The ridge continues to remain influential over the weekend with the high centred west of Ireland but by late Monday it is coming under pressure from two directions. One from energy/troughs leaving the eastern seaboard to the south west and the other as energy sweeps around Greenland and south east towards the UK all of which has the combined affect of disrupting the high cell and bringing some rain into the north west

As can be seen by the last chart a shallow wave has formed on the front and this deepens and tracks quickly east be Oslo by 12 Tueday with the front edging south over Scotland. This front represents the delineation between the cold air to the north and the warmer to the south west.from where pressure continues to be exerted on the high.

Within 24 hours, by 12 Wednesday, this pressure has split the high with the main centre now over Iceland whilst simultaneously the aforementioned front has cleared the south of England and the surface wind veering bringing the UK once again into a cold, unstable, northerly airstream which lasts until the end of the week. But as always this period is still very much subject to revision.

 

 

 

Edited November 29, 2017 by knocker

[Mucka]

control run takes a little while to get going but gets very cold.

But a chart for Sidney too. Cold lovers look away now. 

GFS 00z ensembles - a mixed bag.

Edited November 29, 2017 by Mucka

[tinybill]

 

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=6

 

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

 

all i can say  for  the coldies is  the charts from now to fantasy land are to many  to repost!!

[ArHu3]

1 hour ago, Steve Murr said:

Hi @SylvainTV

any chance of getting UKMO 168 on meteociel?

thanks

Steve

Or ukmo fixed in the meteociel android app? It only shows recent +144h

[Scandinavian High.]

If the gfs is right lots people could be seeing snow at some point next week heavy snow showers blowing in from the north. Then later on in run maybe an easterly. 

[Mucka]

ECM pretty close to UKMO at 120

Edited November 29, 2017 by Mucka

[sausage]

loving the gfs this morning!! please oh please. 

[Rocheydub]

Do not like how the ecu is evolving post 144, it’s behaving very different in the Atlantic and on the eastern US seaboard and even around Iceland. I hope it’s wrong... 

[radiohead]

ECM is definitely  not as good as the GFS at T168...

[Mucka]

Quite a storm at 192, it may actually end up okay eventually but just another doubt sown.

[terrier]

Great gfs and ukmo this morning happy with that. Ecm not looking as good as the gfs at 168 but hopefully it will change its tune later this evening. 

[ArHu3]

7 minutes ago, Mucka said:

Quite a storm at 192, it may actually end up okay eventually but just another doubt sown.

So pointless now for as long this storm is on the table to look more than 72h past it when /if it happens as these seem to greatly influence what happens afterwards and the models have a lot of difficulty to predict what happens after them. Expect some surprise model output the 4th of December 

Edited November 29, 2017 by ArHu3

[swfc]

Ecm looks fine on the nhp.day ten should be spot on!!! Drop that low south east and game on.it won't be there prob later today but nhp looks good either way

Edited November 29, 2017 by swfc

[Mucka]

9 minutes ago, ArHu3 said:

So pointless now for as long this storm is on the table to look more than 72h past it when /if it happens as these seem to greatly influence what happens afterwards and the models have a lot of difficulty to predict what happens after them

Yes looking into FI is usually just for fun anyway but when there is a lot of volatility in the nearer term it is certainly not worth taking seriously.

In actuality this mornings ECM is a big improvement over yesterday mornings out to the mid range thought it may not seem like it.

All our troubles would be over if the trough would just sharpen and dig SE quicker as shortwaves would be kept West of Greenland instead of pushing through and phasing with the Scandi trough.

 

Edited November 29, 2017 by Mucka

[radiohead]

The deep low that gets blown up on the ECM looks a bit suspect. Would not be surprised if it vanished on the 12Z.

[mountain shadow]

Ding ding round 3 from the ECM

It's never good when the cold keeps getting delayed.

Hopefully this evolution will be removed by the  12z.

[The Eagle]

Given the ECM supreme performance during hurricance season - and the fact the GFS was completely hopeless - I know what i'd be betting on!

[That ECM]

Gfs is a fun to view and certainly would bring some interesting weather. Ukmo, as far as it goes t144, looks to be building heights to our nw. Most interesting to me is ecm throwing a storm from the nw and this still doesn't stop the output from trying to build heights in the nw. 

Various different takes on what might be thrown at the potential heights but what ever happens heights to nw is the consistent theme. Loving the output watching at the moment, very interesting and chances of seeing something country wide increases imho. Detail is detail and should be left for t72 down to t0 but the theme is a goodun.

Edited November 29, 2017 by That ECM

[Stozzy]

Ecm doesn't look right too me . I would be fairly confident that won't happen between 168 and 192