Model Output Discussion - 1st February Onwards 12z--->

[johnholmes]

interestingly, the noaa 8-14 day anomaly chart appears to be building high in more over us. all part of the sequence its been showing for several days now.

 

yesterday mornings ( i dont view in the evening)

 

 

 

As far as I know mushy, they are issued each evening?

[Captain Shortwave]

To be fair these colder synoptics have been showing since the past week, with increasing support.

Just variance in how the cold arrives, I say the likelihood of a colder start to March is much greater than a milder start. Looking at the ECM it seems essentially rather dry, more so the further north you are.

But very cold. +240 has -8C 850s tucking in the far SE. I'd expect the forum to be more busy...

Also March sun can start triggering off convection I do think March is not a closed doors month.

Not great model output if you are mildie! Something is definitely bubbling and frothing.

image.jpgimage.jpg

The GFS is going to have to be on the money here, very little wriggle room to develop a snowy easterly synoptic as you need the deep cold as well as low heights to develop instability. If that doesn't happen it just ends up dull, cloudy and feeling cold rather than being truly cold.

The ensembles are clustering mainly around heights near or over the UK (especially the ECM). That doesn't sound bad for those who are searching for pleasant springtime conditions as the initial cold prior to the high being slowly worn away by the increasing 850s temperatures and the increasingly strong March sunshine.

At this moment I would prefer to see the output go one way or another, as the half way house of a slack easterly is going to result in a lot of moaning (March is probably the worst time of year for slack cold easterlies) 

[mushymanrob]

As far as I know mushy, they are issued each evening?

 

yes i know john, but i dont view them until the next morning as a rule... so when i say 'todays' or 'this mornings' im of course referring to the previous evenings.

sorry if that confuses anyone.

[Mucka]

Certainly a sign of the weather settling down into early March as pressure builds from the SW as expected. I said sometime ago blocking would likely be MLB again though there is some potential for it to get into higher latitudes based on current output - that would include a more favourable Scandi high that could drag in colder uppers rather than Sceuro high set up we have seen this winter which is of little use tom coldies.

 

Much too early to call a cold March but mild looks increasingly unlikely.

As well as looking for ECM to provide a little consistency and GFS for support I will also be checking if GFS ensembles show any sign of supporting a favourable block  before being drawn in as the associated 10 day anomaly charts have looked disinterested thus far. 

Edited February 25, 2015 by Mucka

[nick sussex]

Further to CS's post I agree re an either or scenario.

 

Unless you get suitable instability and sufficiently cold uppers then an easterly in March turns out to be miserable with cloud coming in off the North Sea.

 

For this reason its essential to get an injection of colder Arctic sourced air into the circulation this can then get advected westwards into the UK.

 

The actual trigger for the ridge extension ne is between T144 and T168hrs:

 

 

The troughing to the west at T144hrs responds to more amplification upstream and then digs further south into the Atlantic at T168hrs:

 

 

The effect is to force the ridge ne, the more dig south of the jet the better if you're hoping to develop colder conditions later on.

 

We're not really talking deep FI here the initial trigger is earlier but its crucial to get that digging trough and some WAA to develop the ridge.

 

 

[winterof79]

Come to daddy....thats a building" block" for starters

 

Looking promising for late winter cold.Perhaps the block will be in the right place for once....it is normally always too far east or west of us

 

Edited February 25, 2015 by winterof79

[mushymanrob]

.

 

Much too early to call a cold March but mild looks increasingly unlikely.

 

 

looking pretty average to me sir! it might be cold or it might be mild for spells, but average or normal would be the best bet imho .

[Severe Siberian icy blast]

The 12z is so much more amplified than the 06z was , are we about to enter into the first deep cold spell of the winter ? It's developed right under our noses at a relatively short time frame as always ! ironic really !

But not saw this much potential in a long time !

[MR EXTREMES]

and how ironic solar activity has dropped away like a stone.

but of coarse be silly to speculate or would it!.

 

would not surprise me if we see a below average march and april at this stage 2008 april snowfall south coast ok only a morning event but certainly shows it can happen.

 

but the eastern north eastern block has been popping up a fair bit!

 

and to be fair the ecm at 168hrs is not a 100% but its something to watch in future runs.

but im very confident and have been watching the solar cycle starting to show a decline and am very interested to see if this continues and what knock on effect it has.

 

ukmo is not far of this mornings ecm at 144hrs

ecm this mornings run

 

but i will be watching with great interest over the next few days.

i do believe a cold spring is a strong possibility.

 

 

 

 

 

1 year ago today.

 

november 2014 

much more active than now.

hopefully a continued decline and spotless by next autumn.

 

although spring might roar in like a snow leopard 

Edited February 25, 2015 by emotional rollercoaster

[nick sussex]

image.jpg

The 12z is so much more amplified than the 06z was , are we about to enter into the first deep cold spell of the winter ? It's developed right under our noses at a relatively short time frame as always ! ironic really !

But not saw this much potential in a long time !

Lol you've just jinxed it! The UKMO isn't as good at T144hrs but develops a runner low before then at T120hrs, haven't worked out the 850's ahead of that yet but unbelievably if that's favourable it would be exactly the same day as March 1995.

[Harsh Climate]

To be fair these colder synoptics have been showing since the past week, with increasing support.

Just variance in how the cold arrives, I say the likelihood of a colder start to March is much greater than a milder start. Looking at the ECM it seems essentially rather dry, more so the further north you are.

But very cold. +240 has -8C 850s tucking in the far SE. I'd expect the forum to be more busy...

Also March sun can start triggering off convection I do think March is not a closed doors month.

Not great model output if you are mildie! Something is definitely bubbling and frothing.

image.jpgimage.jpg

 

To be fair, a few runs here and there flirting with this kind of idea/set-up hardly constitutes as great support...

 

Get the ECM and eventually the UKMO on board, then It will gain my interest

and how ironic solar activity has dropped away like a stone.

but of coarse be silly to speculate or would it!.

 

would not surprise me if we see a below average march and april at this stage 2008 april snowfall south coast ok only a morning event but certainly shows it can happen.

 

but the eastern north eastern block has been popping up a fair bit!

 

and to be fair the ecm at 168hrs is not a 100% but its something to watch in future runs.

but im very confident and have been watching the solar cycle starting to show a decline and am very interested to see if this continues and what knock on effect it has.

 

ukmo is not far of this mornings ecm at 144hrs

ecm this mornings run

 

but i will be watching with great interest over the next few days.

i do believe a cold spring is a strong possibility.

 

 

 

 

 

1 year ago today.

 

november 2014 

much more active than now.

hopefully a continued decline and spotless by next autumn.

 

although spring might roar in like a snow leopard 

 

 

I wouldn't worry about that, if the wind comes from the south in spring it will be warm  

Edited February 25, 2015 by Harsh Climate

[Captain Shortwave]

I guess it is a good thing that all the models that go out to day 10 are playing around with blocking solutions.

GEM has a Scandi high

Though the south easterly on this will likely be dry and cold, though I suspect there would be some sunshine given the drier continental feed.

 

The GFS delivers some snow flurries from a north/north easterly flow, but the high splits with a weak ridge over the UK and the Scandi high gets sucked into the Russian block.

There does seem to be an increasing signal for a block to form over north Europe potentially with low heights becoming cut off to the south of this. It is just a question of whether we can get lucky.

[Daniel*]

To be fair, a few runs here and there flirting with this kind of idea/set-up hardly constitutes as great support...

 

Get the ECM and eventually the UKMO on board, then It will gain my interest  

More than a few, GFS was the first to hint of this all way out in FI most were taking it as a no go like myself but it is coming closer to reliable, it does not look like a 2013 perhaps a 2005 if we can get lucky. Let's say if we were getting dished out these charts in mid winter it would be a lot busier. ECM is the leading the way if it is more substantial cold on the morning run. GFS 12z might have taken a little wobble but it is still cold stuff with cold air close by, it would not take much to make it something more notable. First 7 days of March is looking below average to me. Not a snow fest or a epic cold blast but interest, all the same, the hunt is still on. I expect by morning UKMO to calibrate more with a blend of ECM/GFS. ECM 12z is awaited with interest. I'm only a amateur so do not take me seriously, well you can if you want. I have a vibe this time.

[TEITS]

Looks like I might be coming out of retirement lol.

 

I have been keeping a close eye on the potential E,ly for a few days now as the GFS had something like 4 or 5 runs on the trot showing this. During yesterday the GFS backed away somewhat but it appears the momentum has swung back towards an E,ly today.

 

The important trend I am keeping an eye on isn't just if the block to our NE develops. A few weeks back I posted about the importance of having a surge of cold air out of the arctic prior to an E,ly and due to being March this is even more crucial.

 

So keep an eye on the period between +144 to +180 to note how cold the air will be sinking S and then if the orientation of the block is favourable to advect this back towards the UK.

[IDO]

^^^Yes the GFS control shows how we can get a short lived cold feed (3-4 days):

 

 

 

The GEFS are slowly coming on board but the op and control are leading the pack for the above synoptic:

 

 

 

As the GEFS go past D12 the few zonal members gradually blend towards a less westerly flow and by D16 the UK looks to be more settled.

 

D16 mean: 

 

Early days yet for any conclusions...

[KyleHenry]

and how ironic solar activity has dropped away like a stone.

but of coarse be silly to speculate or would it.

You've got to allow for the lag effect. You'd need low AP flux, radio flux and sun spot numbers to continue as it is now for approximately another 5/6 months to see any effect.

Less energy into the tropics then the lower the forcing is on the jet stream to displace it to its traditional home North of the British Isles. Resulting in a cooler and wetter Summer. Consistency and more time needed.

Edited February 25, 2015 by Paul
Fixed quote

[SMU]

evening all

Well the cold brigade will be musing over the models tonight wishing these Synoptics had landed sooner -

However the ECM & GFS at 168 & 192 are almost worth a boom comment as the -10 line starts to head towards the uk

Certainly the last 24 hours has seen modelling align to a more & more amplified pattern

The key as ever is to get the link between the Russian high & Atlantic ridge to centralise pressure over Scandinavia - thus delivering the easterlies to the UK ( like the GEM )

Interesting times

S

[Ali1977]

-12c 850s not far away at day 10....hard to get excited at that distance, and nothing from the METO saying a very cold early March is possible... Shame it wasn't Jan!!

[nick sussex]

I think the IF ONLY phrase might be appearing often over the next few days if tonights trend continues, however early March can still deliver with the right set up.

 

The ECM was a bit too close for comfort at T144/T168hrs and a bit more progressive with that upstream troughing , after the initial scary moment it does deliver a great looking high towards days 9 and 10.

 

A big help would be low pressure further west in the Med towards northern Italy but overall a good ECM run. Because of the expected movement and orientation of the PV essentially if things come together favourably between T144 and T168hrs then theres a very good chance of an easterly.

 

The question mark for the UK in these situations is often trying to get a direct hit from the coldest uppers from the east.

 

The ECM does look cold enough towards the end with those -12s 850's, it would be nice to see an even colder pool to the east, but that's well into the future.

 

The biggest hurdle is getting the ridge sufficiently north to begin with so its crucial that the upstream pattern plays ball upto T168hrs.

[Daniel*]

-12c 850s not far away at day 10....hard to get excited at that distance, and nothing from the METO saying a very cold early March is possible... Shame it wasn't Jan!!

These charts are not at day 10, D5/D6/D7/D8, and that is just the starter.

Very good run as a whole you can just see past D10 the cold will not be in a hurry to budge.

Edited February 25, 2015 by Daniel*

[chris55]

March Battle ground lol !

 

[Mucka]

looking pretty average to me sir! it might be cold or it might be mild for spells, but average or normal would be the best bet imho

 

Just because that is the norm or do you have some further insight Mushy?

 

There is a strong suggestion that the first 3rd of March will come in below average, certainly no mild synoptic showing which is why I suggested that a mild March is looking increasingly unlikely. An average March is covered in that statement so I'm not sure where your area of disagreement is?

 

If you are calling an average March then are you saying the first 3rd won't be below average or that it will be but the rest of the month will be above average to make up for it? 

Edited February 25, 2015 by Mucka

[Winter Cold]

Well it seems the models have enticed some of the big boys to return! Il take that as a plus!

 

Ive been posting the promising charts all week and flying the cold flag and its nice to see it gathering some support. Todays runs have certainly upped the stakes, with crucial developments now at T144 so not the deep dark realms of FI so we should know the final outcome soon.

 

The very nice charts have already been posted this evening so ill not clutter the thread by doing the same.

 

[knocker]

Oh well I'll clutter along with the GEFS T240 mean Anomalies which haven't drastically changed.

Charts courtesy weatherbell

Edited February 25, 2015 by knocker

[damianslaw]

A lot of interest in this evening's charts, both ECM and GFS continue to suggest a significant change through next week as we loose the influence of the atlantic and exchange it for high pressure building in quickly from the south and for the first time all winter heights are shown to ridge sufficiently north to enable an easterly influence.

 

As others have commented, too early to call how far north such heights will build, but the Jetstream profile supports ridging to the north - a split jet is shown with greatest amount of energy in the southern arm, hence no reason to call off chances of an easterly developing.

 

In the meantime lots of topsy turvy weather, a brief mild blip now, cooler tomorrow and Friday, another brief milder blip Saturday more so in the south, then chilly Sunday-Tuesday with snow to low levels in the north.

 

Early March can be as severe as anything Dec, Jan and Feb can produce in terms of wintry cold weather, especially thanks to the fact the arctic is colder now than at any stage of the year.