Ill delete then and add the link

http://www.wpc.ncep.noaa.gov/discussions/hpcdiscussions.php?disc=pmdepd

Thank you 😊

Didn't mean to sound like a moan, it's just that it made the other posts look really small meaning I had to zoom in to them😕

I wish you all the best with that Steve I wish you would post more often.

While im on the subject of "wishing" may I wish all two members a happy and very safe new year

ECM ens anomalies paint a soggy picture with a deep trough plonked near/over the UK at days 7-10

At day 12 the NAEFS pictures a similar picture, continuing unsettled with temps well above average across Europe.

Nearer term, a risk for a time of wintry weather into the the far NE and E as the cold pool tries to make it West but looks low risk at this stage. Best place to be is Shetland..

Thanks Martin for all your reports input into this thread this year it must be hard work I look forward to reading those again next year.

That seems a pretty accurate overview overall 

Good luck with that call as well Steve. Personally I am not confident enough to call anything beyond uncertainty. 

I just hope the rain up here is not as bad as forecast (the Met Office now have 3 days of warnings out) 

On the subject of uncertainty, like the 00z GEFS, the 06z ensemble set also highlights a large range of options for the potential cold incursion from the east up here. http://meteociel.fr/cartes_obs/gens_display.php?ext=1&lat=57.2&lon=-2.3 

 Indeed Brian, Just fab Thanks Darren

Appologies for any spelling- tapping on phone

Just to add to me comment from earlier as I have half hour -

I can assure everyone I wouldnt just post & comment If I didnt believe it would have a strong probability of happening- I have been saying the same for days on NW but maybe not as clear & as loud -

As it stands there is no ensemble support ( less than 10%) for what im saying but im drawing on what ive seen over the last 14 years - watching every run ( winter ) of the AVN > GFS UKMO & ECM right back to the old snowatch days -

I guess in those 14 years the amount of runs modelling scandi / Russian highs delivering deep cold to say debilt at 120-144 have been averaged about 2/3 a year ( obviously thats all the runs for 1 outcome grouped together each time )

& of those 40 odd scenarios the deep cold has penetated to the UK probably a third of those occasions - my memory highlights
Feb 2005 , Feb 2009 , dec 10, jan 13- Mar 13 ( rem the undercutter ) but of course some more - also the pain of many failures-

I would also add that across those 40 scenarios as a rule of thumb the AVN / GFS is as useless as they come - & to top that the GFS ensembles are the cherry on the useless cake -

The ECM has performed well - however its lost some of its kudos in recent years -
The UKMO has been pretty consistent but of course has occasionally got it wrong-

I would like to think I know where to look when seeing these models & what their weaknesses are -

GFS never seems to model the scandi blocking well but also its secondary weakness is not having the resolution to seperate parcels of energy ( PVA )

So when you have a scandi block & are reliant on the models deciphering how much energy is seperated & heads SE so the GFS is at its weakest - it will always move the jet through the block at a NE angle until it gets to grip with the real solution - this often arrives rapidly in the 96-120 arena on operationals & usually a day later on the ensembles - so the integrity of the GFS suite today at 144-168 is pretty flakey.

The NE angle of attack is then replaced with a SE angle of attack -

The euros will be much more realistic & should be prone to less swings ( again ECM has been showing occasional inter run volality since the upgrade - )

Its also become more apparent to me that theres ALWAYS a trend in the days modelling - sometimes its blindingly obvious - sometimes more subtle-
I look for these trends in the places that will impact the Uk in the following days - so thats not overhead -& in this scenario its the development & angle of the dreaded shortwaves coming around the high over russia - to the angle of the waves exiting the coast of the US-

These nuances & changes at say 72-96 are the ones that have the 'big' impacts on the pattern at 144-168
I find this far more interesting than chasing future possible teleconnection changes as they are far more specific to the UK- which in my view is of course more important -

Anyway-

We are at the exact point today where a CRITICAL element of the resolution of the energy distribution will have large scale impacts on the pattern feeding Europe ( NW ) including the UK at 144-168

The models for probably 4-5 days have had the MAIN low arriving at 120 stalling out somewhere close to the NW of the UK allowing energy underneath to be sufficient to keep the deep cold east past Debilt-
They havent allowed any lows to 'turn over' & advect the cold back west...

ECM & GFS 00z both support this scenario by developing a wave off the gulf at around 84-90 which aubsequently gets swept up in the eastward jet ( flat no amplification ) this wave then comes under the parent low at 144 & slides across southern england giving a very brief continental flow on its Northern flank - (ECM 00z + GFS 00z)

However as the flow behind it sees additional phasing of low pressures in the atlantic & the subsequent development of the deep circular low - it all sweeps east with ease-
Goodbye block-:(

Also to the NE towards Norway the models have placed another shortwave with low heights there traversing WNW- this again stops the block forcing ESE towards the UK.

So in isolation - theres just 2 shortwave features both conspiring against the UK for cold...
But what if the trend of the day was to change the modelling of these in terms of positions?

Well then the longwave pattern will follow-

Its my proposal that as we reach 72-96 the models will resolve the heights over Norway & across to iceland & as a result will display heigher heights that originally predicted -
Vis a vee the Cold air advection heading westward out of the continent will have more directional forcing WSW not WNW


Now to address the atlantic profile -

The initial deterministic resolution shows a flat jet with one wave exiting the US on a trajectory with the south of the UK under the parent low, but what if the models are going to react to the downstream changes of heigher heights over Norway with upstream teleconnective changes of more accute amplification - IE creating a ridge with perhaps 2 areas of energy exiting the states -

If this happens & you throw a ridge in there then you get an inflection point - the sharper the ridge the sharper the inflection point-

All of sudden the wave heading for the UK becomes very very shallow & recurves south towards spain & portugal ....
Whilst the other area of energy - again becoming more defined & deeper as it traverses a steeper thermal gradient into the lobe of the vortex goes NORTH west of the big low over the Uk-

The net of the this is all of a sudden theres energy heading south to portugal as well as a ridge building over the top of our UK low - forcing it south ( not back NW as the GFS keeps doing )

Bonus wise here is the fact that there no immediate energy against the block over southern england -
We then allow the CAA to burst west into the UK ( as long as the low exits southern england & doesnt stall )
If it stalls in the south then its just the North that benefits from the Easterly flow.

So these 2 key events - if they are the trends of the day & what ive seen the atlantic ridge has shown on the
* UKMO 00z
* GFS 06z ( not acute enough )
* JMA 06z t84 has the ridge
* APERGE 06z t72 has a ridge forming..

I would expect a significantly different suite tonight in favour of cold.
Its happened before - I have called that before ( but of course I have also not been right )

Take it or leave it :)
S

Cheers Steve, Post more often if you can, lets hope your telescope eyes has spotted something, by the way that post must have been murder on your phone 

cheers doc + PL

1089 words it said ( which is a nice touch on here )

I do login here every day - will enjoy posting more -

& the name on NW ( if anyone was wondering ) is in jest ... Nothing serious

S

I wouldn't disagree wih that Dave

Thanks for the clarification Steve, my view is that the GFS is right to identify the shortwave off Southern Norway which prevents and South West extension of the High; though to be fair the jet is well enough North for this not to be an issue anyway. 

For me there is nowhere near enough uncertainty in the models (I too have 14 years at this) for Steve's outcome to be correct, yes the dividing line may end up closer to the UK than some of the more progressive runs, but the margin for error, for the bulk of the UK in this instance  is such that it won't matter.

30 minutes , blimey Steve I'd need 4 hours for that sort of post

A good read indeed

 That's a factual statement no one can argue with. It will either be right or wrong and we'll know in the next few hours. Unfortunately my NY celebrations are starting shortly so may not be able to check until tomorrow.

Sort of on topic

What is the criteria for a LP to be named??

No one ( media ) is giving names to the LP's that are due in the next 72 or so  hours ???

http://www.wetterzentrale.de/pics/Rtavn481.gif

http://www.wetterzentrale.de/pics/Rtavn781.gif

http://www.bbc.co.uk/news/uk-34578310

Not sure Marcus but this link suggests where the names come from.

Nice to read Steve Murr's post. Its fresh to read someone who has the guts to commit to a belief even if the outcome is not what people are hoping for. If I had your knowledge Steve regards model watching I would want to share it with others, but I like to sit back and learn from such as you. There are some brilliant posts on here from some very bright individuals. Keep them coming please. Here's hoping for a proper cold spell. Happy New Years to all. 

StuH

FWIW I don't think there's anywhere near enough certainty in the models at the moment for us to be sure that the atlantic will continue to prevail as per recently. It's a finely balanced situation that could still very much go either way.

This is the key sentence and a direct quote from the Met Office website:

A storm will then be named when it is deemed to have the potential to cause substantial impacts in the UK and/or Ireland.

I would imagine this means a storm will only be named from a UK perspective if the Met Office expect to / are about to issue an Amber warning or above. Yellow warnings (what we have at the moment) are unlikely to trigger a naming. Bear in mind that a storm can still be named even if there is unlikely to be much UK impact as Met Eirann can name a storm if it will impact Ireland (both Clodagh and Eva were named by Met Eirann).

Will lets see then. 

I fear that you will be wrong Shropshire as the weather at the moment is not worth model watching 

Cheers GW; I missed the important bit in my own link!