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Not one single shot of the UKMO 72 At least it will be dry...

Spring warmth we have a problem

Doesn't this one look like a giant freezing Monty Python style foot coming in? Tapping the big toe too. ICON at T57. And it looks further north than the 12z which is perhaps more pertinent.

Off topic sniping posts over who gets or had the snow last time have been removed.Please let's be grown up and keep on topic. Thankyou.

We are moreso primmed via easterly no-2... Than previous. Everything ripe for notable pop up features and convective influence...as highlighted via sea temp annoms. Think a few will be shocked/alarmed by precip-totals as we gain the overall influence of the inflow... 12z will likely prove fruitfull of highlight!!?? Impressive-temp gradients via graphical outlook..... Well into march!!!! Look forwards to todays 12z suites.. I feel upgrading of impacts...incoming!!!!

Yes ^^ Snow cold & instability extends from early doors Sat to Late Sunday- More than enough time for inches of snow to fall Entry point smoothes to around Suffolk / North Kent of the core - Circa 2009 Feb...

Hopefully tonights outputs so far will cause some to refrain from the wrist slashing which has been evident over the last few days . You know who you are! The UKMO has a wider area of instability and a stronger flow, having been the least interested it’s now on board . The GFS manages to hold the high further north for longer as some trough disruption upstream feeds the Euro trough . The GEFS mean at T90 hrs has edged the pattern further north and increased the instability .

So it looks like around two days of convection Saturday into Sunday , perhaps a touch longer in the far se and then drier but still cold on the ECM for Monday and Tuesday. Plenty of time for some good snow totals and then sledging for the lucky areas. If this is to be winters last hurrah then at least it goes out with a bang .

Nice post & just to add to this - Ive often thought of how to forecast snow without the aid of models due to there inability to quantify PPN totals from Streamers - you can do the same for anywhere but The following parameters are important: This is a very crude way - A) Timeline of optimal instability - 24 hours B)Max PPN rates from showers - ~2cm per hour C)% of time You can optimise from the optimal instability time - max 75% (0.75) because the streamer locale usually changes. This means the equation to the 'top out' values at sea level is A X B X C so my forecast sweet spot at sea level would be 36cms within the window available. In terms of elevation ( again crude ) based on reports I have seen from scotland then corresponding reports from Glencoe - that when sea level got a fall of 15cm, the Glencoe car park would be 2X (600M) ~ 30cm So I would go with a 0.33 increase in depth per 100M Tops of the downs are @ 200M Mostly - So 'top out' for the downs would be 59CM. This is on a par with 2009 where low ground of NW kent got to 30-35cm in a 30 hour window & the high downs were in the 50's. Taking the beast from the last week the GFS ppn rates/ snow depths look to be about 5-8X to low under convection where as the high res models like Hirlam / Aperge feel about 1.5X to short Best S Remember that top out forecast. 36cm which is in the streamer sweet spot location TBC?

Interesting indeed, time to update the swing-o-lol-o-meter A very noticeable shift north when all seemed to be heading south. Quite the turnaround and some go for a clean easterly passing right through the whole of the UK. The purple runs are where somewhere in the UK has -5C uppers right until next weekend. Given the cleaner easterly the potential for for energy slipping uunder the high is there which would in turn keep the Atlantic at bay and perhaps set up a northerly. Still a bit tricky, however don't rule out a comeback of the fabled purple line...

No, the SE in general did very well last time, the only way the SE is going to miss out with Northwards corrections is if it corrects so far North that mild air gets mixed in and turns it to rain, and that's never looked likely in any of these 2 Easterlies.

When we've done with the Beast from the East the Gfs 18z produces a Beast from the North with further snow!..loving spring so far!

High res NMM Europe showing the extent of the cold air moving west over the coming days quite remarkable to see it so cold so late 850's 2m temps

Ecm and icon come out of this with kudos if today’s 12z’s thus far are on the money whats the betting ecm 12z takes the cold pool through Milan !!!!!!!!!

Not sure how many times this has been said before but convection forecasts on any model are useless. The only thing they are better as is frontal precip. Yet still there’s loads of drama in here over forecasts which have been been proven to be a waste of space in the past.

The shortwave arriving from the east blocked the easterly flow for about 12-18 hours last time... Anyway - boomtown on the 18z at 66 It looks like a historic chart from the 1800's

Some lovely wet snow from Boston, USA last week... the cold weather is definitely following me around as I have just got back from there! Fingers crossed for a snowy birthday on Sunday!

Snow Gone to much north again This will mean less likely for south east England like last time

No sign of the updated fax charts . No day 3 ,4 , or 5 out yet. Perhaps they’ve been embargoed to stop the supermarket shelves from being emptied!

Lets just hope this cold spell isn't as severe as last time, we all the remember the chaos it caused on the tube!

Even at my advanced years im going to do an Open University course during the Summer,this will get me ready for Model Discussion next Winter,you need to be very knowledgeable in the areas of sniping,backbiting,post reporting,ignore button use,if your lecturer feels you are adapt at all of these skills,whilst having limited knowledge of the weather,you get an Advanced Clueless Diploma,which allows you into various forums of this kind.

UKMO further north Today Yesterday

Over the last 24 hours the cold spell has been extended at both edges - Cold coming in earlier & further North, & the exit point of the -8c line now seemingly late monday eve.... Talking of powder this was West Kingsdown on the last beast

So then, slowly we are seeing the models converge on a solution regarding this weekend. So tomorrow we will see a front slowly move north east bring rain and a stiff south easterly wind. This will clear later in the day but it will never be that far from the coast of Norfolk and Suffolk. Friday - Another area of rain will push through the UK but will begin to struggle to clear the east coast with the fronts beginning to move back westwards overnight, as colder air arrives from the east this rain will turn increasingly to snow. Saturday - The front will steady clear westwards with snow becoming lighter and patchier, sunny spells will follow with snow showers initially developing near to the coasts of Norfolk and Suffolk, overnight we will see convergence lines along the Wash and Thames with areas in line with those bodies of water seeing significant amounts of snow (10cm possible with some drifting in a strong ENE wind). Sunday - We will see heavy snow showers during the morning, these will tend to ease off a bit later, conditions will slowly turn less cold next week with sunshine and overnight frosts.

True - and shockingly mild throughout most of the UK according to GFS 06z

Pretty much a direct hit on the EC this morning. Should be some heavy snow showers around at the weekend.

Right some contradictory posts here which new members must find completely baffling. I'll tackle each issue that has been raised... 1) The easterly is trending south. Somewhat correct The UKMO hasn't really pulled this further north that often but looking at the GFS runs is there really a trend south, lets see... the below map shows where I think the boundary will be where the air is unstable enough to develop heavy snow showers on midday sunday Yes there is a trend south though not fully consistent, its tiny differences and the 12z for example saw something slightly further north then the 06z 2) It will be a dry easterly. Incorrect The 18z still shows a streamer of snow showers in NE England moving down to the Midlands on Sunday. Also the 12z showed something pretty similar. 06z saw synoptic conditions favourable for more widespread snow showers despite slightly more stable heights. The 00z was admittedly far snowier Also take note of the curvature of the isobars which is cyclonic over SE England indicating conditions favourable for shower development. The models will underestimate convection. 3) It will be a short sharp cold snap. Correct It will probably start on saturday and ease on Monday though very cold minina will go on for an extra day or two longer. In the sun it won't feel too bad especially later in the week if rain holds back. However the cold this weekend will be exceptional. A quick breakdown looks very likely now but will see if the swingometer shows any surprises. I doubt it will, the issue is a lack of instability to our SSW which encourages the high to sink and give way. A snowy weekend for some! a few members will be disappointed unfortunately but you usually get winners and losers when it comes to UK cold spells. Come mid April I'll be joining summer sun in chasing spanish plumes from the south rather then beasts from the east but its been a good effort so far this March!

What about the snow? Boom boom lol

I always have a chuckle at the yellow snow label

Nice morning here with plenty of hazy sunshine and a mild 12C, but that SE’ly wind is pretty gusty. Looks like our region is best (or worst, depending on preferences) placed to see some snow this weekend. Unless that high sinks too far south, still time for that to happen. My pepper and chilli plants are doing well under my new toy (Grow Light Garden by Garland) ???

Good news, latest FAX chart has moved everything slightly further north again. T84/00z today T96/12z yesterday

No change to the 00z models, a bitterly cold weekend, especially further south with a strong Easterly flow across southern uk bringing some snow..temps struggling to get much above freezing and feeling sub-zero due to severe wind-chill..becoming progressively more settled and sunnier further north due to high pressure but cold everywhere with sharp overnight frosts..winter is returning!

I think regardless of on the ground conditions, I'd argue that is a historic cold shot for the time of year, given SST's are surpressed from the earlier beast, could see some cold daily records go if we get enough snow on the ground during Saturday.

It got on at Canada Water.

For this time of year, these charts are incredible from the Ecm 12z and there could be some disruptive snow out of this, especially across the south, almost unheard of to get 2 Beasts within such a short space of time..enjoy it coldies!

good afternoon gang ,There certainly is potential for Snow this weekend ,over many years of weather watching ,in this sort of set up forecasters wont stick their necks out too far because fronts etc can evolve very quickly in deep cold air .Already today Warnings have gone out for variouse parts of the country ,and although at the moment we are just outside the warning areas There could be a big shift tomorrow , Fax charts ,curtain twitching Radar and Lamp post watching on the menu again folks .Now food ,hot crispy sausages in bread with brown sauce ,crackly belly pork ,breast lamb stuffed, with chips BUT i do have a healthy day three times a week with veg fruit and some protean ,as i promised my Late wife back in November that i would look after myself .No one to tell me off now if i make the curtains dirty when Twitching ,well gang evening charts are on the way , best of luck to all that like the magical snow ,.

Yes it's always re-assuring when the UKMO comes on board at this stage Nick. Looking at the 00z ens and comparing 12z outputs so far there could be up to a 3 day window for snow fall in favoured locations where we have some effect from that upper cold pool plus any streamers that crop up.

Big improvement on this evenings UKMO compared to yesterday's and slight improvement on GFS with the high further NW and stronger Easterly feed. UKMO yesterday/Today Hopefully ECM follows suit and we can get further corrections NW which would give more areas of the UK a chance of snow and prolong the cold somewhat. Based on current output it doesn't look like we will get a proper retrograde pattern still with too much Atlantic forcing but it would nice to see the models keep correcting the high further NW to allow a reload from the NE

UKMO day 4 versus yesterdays day 5 vs That is a significant shift in the speed the cold arrives and a northwards shift as well which increases the chance of more widespread snowfall. GFS The cold pool is slightly slower but more intense which would bring heavier precipitation to favoured spots. Again this is further north than this mornings runs.

Starting to look like the models are following a similar pattern to last time: 1) spot the easterly in FI; 2) toy with dropping it; 3) bring it back again, but then gradually sink it south over a few runs; 4) correct back north again closer to the actual event.

The latest Met Office early warning mentions a possible convergence zone around the Wash and the Thames estuary . And with the chance these snow showers could spread west. So strength of the flow quite important here, also what happens to low pressure over Southern Europe as that impacts both the flow and instability available into the UK.

Yellow warning for snow just come out

I've taken another look at the ECM ensembles for where the cold pool hits. Below is roughly where the centre of the cool pool goes through. Most of them are well developed enough to affect areas 100-200 miles either side of this (so for instance, most cold pools centred on southern England will probably be big enough to affect N England, and cold pools going through N France will be big enough take in SE England). Scotland: 2 ECM ensemble members North England (Nottingham + northwards): 4 South England (Birmingham + southwards): 25 North France: 15 S France / not really developed: 5 So yes I do agree with you Feb and yes my very quick post earlier was a bit too general - the idea of the cold pool hitting Glasgow is right at the extreme of the options and is probably only a 10% chance, whereas affecting the English Channel is perhaps 80%. However ... while I now agree a Scotland event would be a surprised, a significant snowfall event for NE England cannot yet be ruled out IMO. When I look at historical charts, NE England has often received lots of snowfall on the coast when on the edge of a cold pool and uppers are below minus 12C. Both these things still in play. But equally, to be clear, it is south of the Humber which remains the area of most interest for now. And just to add a bit more using the clusters ... if I lived in N England and looked at cluster 1 (by far the biggest), I certainly would not count myself out of the game if I lived in N England:

What do you expect at 6am in March?! A more sensible time shows double digits quite widely

Morning all It all got a little heated (unlike the weekend's forecast weather) in here yesterday evening. Let's be honest - the weather doesn't care what you want, I don't care what anyone else wants either. There's an "Ignore" option if you want to use it and in any case we are utterly powerless and helpless against the vagaries of the atmosphere - nothing personal, it just doesn't care about you or me. So, all we can do is deal (so to speak) with the cards we are dealt and in that spirit the cards for the morning of Saturday March 24th have hit the table so time to pick up and have a look. Starting as always with ECM 00Z at T+240: A vigorous and deepening LP is moving SE toward western Scotland with frontal systems crossing the British isles bringing wind and rain. Colder air behind the cold front is likely to bring a traditional spring mix of sunshine and heavy showers with snow on hills. The question is whether the LP will continue and ESE trajectory into Europe and pull in some colder Arctic air. GEM 00Z at the same time: The evolution is very different to the ECM. The former takes the HP SW through the British Isles and absorbs it into the Azores HP quite quickly. With GEM the HP remains over the UK a little longer so the Azores HP builds more into Europe allowing the trough to dig further south west of the British Isles. This promotes a mild SW'ly airflow over most of the British Isles and dry for many ahead of the approaching frontal systems which are making only slow progress east. GFS 00Z at T+240: Something different again emphasising huge uncertainty after this weekend. The HP from Scandinavia sits over the British Isles and intensifies giving us a week or so of largely fine weather with improving day temperatures as the colder air recedes but still with night frosts. Eventually, the HP splits with one part going to the Azores and the other heading SE into Europe allowing a weak Atlantic system to approach but this heads SE and the British Isles is left in a slack S'ly flow with showers or rain confined to south western areas. Further into FI the Azores HP becomes more dominant but it transfers into the North Sea as a new MLB leaving the British Isles largely fine under an increasingly cold E'ly by Good Friday. GFS 00Z Control at T+240: This morning's GFS Control at mid-range looks like the ECM OP with a negatively tilted trough close to northern Scotland and a fresh NW'ly flow over the British Isles. Further into FI and the LP disrupts south down the North Sea putting the British Isles into a N'ly airflow and the trough expands with a new LP crossing Ulster heading ESE as Good Friday dawns. The 00Z GEFS at T+240: http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=240 Considerable uncertainty into the medium term with a lot of options on the table. Given a call, I'd say the majority have LP or a trough close to or over the British Isles. 4 or 5 have winds from a SW'ly or WSW'ly direction but plenty of others have Northerlies and Easterlies and the greatest spread is over the British Isles so plenty of confusion, As Easter approaches, there's a trend to build heights either in the mid Atlantic or from the Azores but far from resolved at this stage as you'd expect. In conclusion, a messy and unsatisfactory picture this morning. Any lingering hopes of a prolonged cold spell via retrogression have been extinguished but how the HP passes through the British Isles after the weekend is far from clear. ECM has a rapid transit through to the Azores allowing the Atlantic to play a hand again while GEM has the HP hanging on a little longer promoting a gentler evolution while GFS gives us several days of calm weather as the HP intensifies over us. Given that huge diversity, it's very hard to make a call at this time but the Atlantic remains largely weak and disorganised and the hints of jet movement observed yesterday have also faded so nothing zonal and nothing settled. The tendency for LP to head SE on a negative alignment into Europe (which has really been the story of the European winter for me) continues and while that does it's unlikely to be warm for any length of time.

Yep ^^ Mild on the horizon lets get this weekend out the way first with one last hurrah ! IKON 06z a nice jog North to include a greater portion of the UK

Nice update from UKMO extended at t168 showing milder air starting to move in from the west ECM taking a similar route only difference is a bit more rain for Scotland

For London. Very cold with snowfall the order of the day. Significant snowfall remains a good possibility further south and east.

The envelope remains extraordinarily wide on the 00z suites thanks to gfs whose model suite (op and ens mean) takes the cold pool through e France, close to strasbourg! Meanwhile, ec and icon flying the flag with the former the furthest north across s England. Gem, ukmo in the middle ground over the Low Countries. With ec and gfs at both ends of that envelope, experience tells us that ukmo looks a good call. (And that would be a pretty good showing from the model (if I verifies like that) eps shouldn’t vary too much from the mean at day 4 but they showed a considerable spread on the last run (six clusters) so still to be pinned down I expect from the model. it’s only Wednesday - expecting to know what Saturday will bring apart from cold remains elusive.

It's obviously far too early to attempt to call the possible snow event in the south on Sunday but for the record this morning the ecm has the cold pooll/upper low a little more north and west than the GFS. At 00 Sunday it is in the eastern Channel Over the next 12 hours the main snow belt remains in the Channel as it moves west but the norther edge would impact the south coast. But the main point is the temp which will not get above freezing in many places and in the strong easterly wind the wind chill be very nasty indeed.