Model output discussion - mid January

[KTtom]

Well finally the gfs gives us something to drool over...yes over 300 hrs away but if it' shown it must be possible..

 

Edited January 25, 2018 by KTtom

[Seasonality]

Nothing to see here. Move along please.

[Seasonality]

Although I do always note how mild surface temperatures remain in much of the UK even with fantasy synoptics like the 00z FI. Perils of being a narrow island surrounded by water.

[Johnp]

That has to be the best GFS FI run of all time?

If only eh..?

[comet]

11 hours ago, comet said:

Very disappointing to see the downgraded strat warming by the gfs and to some extent ecm. This at one time was modelled to really bolster the Russian high and Pacific ridge into the Arctic. This has now been toned down to some extent which is not good news imo although I would not be surprised with the recent poor modelling if the warming was forecasted to strengthen again in coming runs. Just my opinion of course.

A post I made last evening and low and behold a few hours later the 0z shows us what can be achieved with stronger strat forcing (warming)and I would imagine a stronger MJO signal. 

Much more amplified pattern on the eastern side to link up with amplified Atlantic ridge While very cold air avected westwards. Fingers crossed.

[Seasonality]

9 minutes ago, Johnp said:

That has to be the best GFS FI run of all time?

If only eh..?

It might just appear on a GFS FI Greatest Hits album, I'll grant you that.

[Ali1977]

Imagine if that GFS became reality - back to the good old days with a 1000 members in here. Something tells me mid to late feb will be epic 

[That ECM]

4 minutes ago, Ali1977 said:

Imagine if that GFS became reality - back to the good old days with a 1000 members in here. Something tells me mid to late feb will be epic 

There is always the chance, with the uncertainty of where the high will drift too. If the professionals don't know then we will have to watch it unfold but we are in the game for a good finish to the winter for sure.

[Penrith Snow]

GFI is great eye candy but it will probably change on the 6z, however, with the MetO now predicting a below average February something must be up and they clearly don't foresee a continuation of the mild westerly dross.

With a GFS run like that and a MetO MRF like we have you would be mad to call Winter Over.

Andy

[Mucka]

Good to see the phantom Easterly make a reappearance in deep FI.

[Radiating Dendrite]

Great run in make believe land. Until we get that within 96hrs I won't be getting too carried away.

A colder than average February could quite easily mean a big fat high sat over the top of us with chilly nights. Cold does not always mean snowy wonderland. 

[Chesil View]

Not really surprising to see the Gfs provide N operational that introduces frigid 850's to the Uk. The runs over the past two or so days have consistently shown 8 or 9 perturbations in between -5 and - 15. On that basis alone any winter's over calls seem way wide of the mark.

[SLEETY]

Ecm look fairly similar at 240 to gfs ,maybe just once an fl cold chart can verify down to time zero

[Seasonality]

4 minutes ago, SLEETY said:

Ecm look fairly similar at 240 to gfs ,maybe just once an fl cold chart can verify down to time zero

I'd agree, they do look broadly similar. God knows I shouldn't be worried about output at that range but I take just a glimmer of optimism from those charts... At least until today's output reverts to rubbish.

[Decemberof2010]

1 hour ago, Johnp said:

That has to be the best GFS FI run of all time?

If only eh..?

I'm sure someone else can clarify. But last year a GFS run showed -17 temps for much of the country and up to 3 feet of snow! But yes it would be certainly up there. 

[Timmytour]

1 hour ago, Ali1977 said:

Imagine if that GFS became reality - back to the good old days with a 1000 members in here. Something tells me mid to late feb will be epic 

'Could be epic' bingo

I believe that's now every bit of December, January and February covered

[nick sussex]

I see the easterly or as it should be named the Terminator you can’t finish it off and it keeps coming back for more returns in FI.

Both the ECM and GFS are similar at day ten, the former more amplified though.

Too early to say whether this is another Indiana Jones search for the Ark of the Covenant.

I know the MJO has its critics but it’s really this which is giving us any hope of seeing some more sustained cold.

Looking at today’s forecasts no change there continued progression east which is going to deliver some changes.

The UK just needs a little luck which is often in short supply so fingers crossed a flow from the ne or east will verify . At least there will be some decent cold to tap into.

 

 

[MP-R]

3 hours ago, Seasonality said:

Although I do always note how mild surface temperatures remain in much of the UK even with fantasy synoptics like the 00z FI. Perils of being a narrow island surrounded by water.

Depends more on the source of cold than anything. Feb 2005's easterly was not overly cold despite Synoptics as much of Europe wasn't either. Feb 2009 or 2012 on the other hand were both decently cold with ice days. 

My concern is it will all be too anticyclonic with the main plunge of cold diverting SWwards.

[stodge]

Morning all

An early(ish) look at the overnight model output on a fine but chilly Thursday morning.

Looking at the output for Sunday February 4th in the medium range models:

Starting with ECM 00Z OP at T+240:

Another day, another tease might be the best way to call this. Obviously, IF this verifies, it would be cold but with only -4 uppers probably rain to low ground but obviously snow to higher elevations on the cards but it is what it is and where it is.

GEM at the same time:

Couldn't be more different. A long ridge of HP going into and covering much of western and central Europe with the cold Siberian air deflected to the far SE of Europe. For the British Isles mild or very mild and generally dry in the south but more unsettled and breezier further north with rain never far away. The jet is well to the north so little or no sign of winter on that chart - indeed, spring might well be in the air with temperatures in the south into the low to mid teens.

GFS 00Z OP at the same time:

A blend ? Well, maybe or maybe not. A large area of HP centred just to the SW of the British Isles is a GFS model favourite - the orientation is more interesting with the ridge aligned NW-SE. That keeps the British Isles in a NW'ly airflow but the air isn't that cold. Note the LP development over the Azores which is profiled very differently to both ECM and GEM and has a big impact on the HP's orientation,

It has to be said the further evolution into FI is about as good as it gets for cold fans. The HP ridges north then NE from T+288 and ends up as an intense feature over northern Scandinavia at T+384. Fantastic eye candy and were it to verify, it would be a significant change to an E'ly regime over the British Isles with increasingly bitter air and the likelihood of snow. For now, though, eye candy is all it is.

GFS 00Z Control at T+240:

One of the reasons the OP FI looks so good is we catch a break in the flow of LP and the strength of the jet to the north. This break gives the HP a chance to build strongly north and then NE. The Atlantic profile on the Control immediately doesn't look as encouraging and the outcome isn't the transition to an HLB we see on the OP but an MLB centred over the British Isles. Yes, it would draw in a chilly NE flow to the south east corner but there's little for snow fans in that.

All I would say at this time is the timing of the possibility of a cold outbreak in February looks about right but so much needs to drop right. Many UK cold spells have started with the Azores HP transitioning to Scandinavia and the OP route to do that has happened before so it may happen again.

The degree of spread across the GEFS even at T+240 is indicative of a model pattern struggling with the lack of clear signals. Many GEFS members are HP dominated though the position and orientation of the HP vary considerably. One or two members (and this wasn't the case yesterday) have pulled the HP further west and dropped the trough right down over the British Isles (this was hinted at in far FI on the 00Z OP yesterday). The big area of difference is off the SE of Greenland.

Think about it - put an HP there or an LP there and the barometric pressure over southern Britain might be similar but that's all that would be similar. Those Downbeat Dereks and Damians who were hailing the end of winter last night might be right but I simply don't see that this morning unless GEM has nailed this. ECM continues to tantalise at T+240 but the path remains unclear so it's GFS this morning which dangles the carrot and IF the OP verified this morning into FI it would be a carrot to savour for winter weather fans.

 

 

[offerman]

1 hour ago, Radiating Dendrite said:

Great run in make believe land. Until we get that within 96hrs I won't be getting too carried away.

A colder than average February could quite easily mean a big fat high sat over the top of us with chilly nights. Cold does not always mean snowy wonderland. 

Brilliant post . Nice to see level head and focus on those charts that you mention . 

[Chesil View]

Just now, offerman said:

Brilliant post . Nice to see level head and focus on those charts that you mention . 

Yes indeed a level headed post...........Although of course so far this winter, cold has indeed mean't a snowy wonderland for various parts of the UK?

Edited January 25, 2018 by Broadmayne blizzard

[Scandinavian High.]

That's proper winter weather and not just for the north southern Britain could be hit hard with heavy snow its a long way out  gfs 6z coming out now I expect theme to continue..

[karlos1983]

21 minutes ago, abbie123 said:

That's proper winter weather and not just for the north southern Britain could be hit hard with heavy snow its a long way out  gfs 6z coming out now I expect theme to continue..

That's pretty much the perfect February chart. you may want to lower your expectations just a touch on a D13 chart, just saying...... it's not got for your well-being lol 

[nick sussex]

Still seems to be a lot of chopping and changing with the initial degree of amplification.

The GFS 06hrs run brings some colder air sw with a more amplified upstream pattern. The high is still likely to topple afterwards but would be good to see some colder air early before we wait for hopefully something more sustained later.

[Scandinavian High.]

North easterly at 168 as upgraded gfs 6z