Spring Model Discussion 18Z 6/3/13 onwards....

[nick sussex]

The Channel Low drama continues,the models have changed tack somewhat with its travel compared to yesterday.

Its not being parked over northern France but trundles along east and then edges more nw between 60 and 66hrs, you can see by this type of set up how difficult it is to get the heaviest precip into the south with it battling against the block to the north.

I doubt this will be sorted out till tomorrow so plenty of time for further changes.

The medium term does look to have good support for a western based negative NAO, in that case the odds stack against the UK in terms of further colder conditions unless that becomes so west based that it allows SM's high to develop over Scandi, it would be an unusual turn of events to get a west based negative NAO but still hang onto the cold.

But the unusual and unlikely have happened in the past so theres still a small chance the cold can hang on for a little longer.

Looking at the fax chart for T84hrs you can see another set of fronts likely to move south, its quite complicated because of the warm sector but still the 528 dam is well to the sw of the UK.

[tom_f123]

Mild but wet looks like favourite into next weekend and in FI at the moment.

[TEITS]

A chart for the long suffering Mushy.

http://www.wetterzentrale.de/pics/Rtavn32417.png

Im sure Nick Sussex would be delighted of temps of 25C across France.

[bluearmy]

Mild but wet looks like favourite into next weekend and in FI at the moment.

mild ?

less cold but not mild tom

[stainesbloke]

Anyone else like me delighted to see mild temps being predicted.

http://www.wetterzentrale.de/pics/Rtavn22817.png

I might be delighted with the potential this weekend/next week but even I have had enough of cold weather!

Yep, I am! Last weeks beautiful Spring warmth was great.

[TEITS]

always said Nick could hold his own with 'em!

Have to say posts like this do irritate me.

I do not seek praise but I do like credit to be given when its deserved. Remember a while back the arguments with regards to the anomaly charts when some of us suggested cold weather was on its way and you disagreed.

Here is a comment I made on the 24th Feb!

"LP moving up from the S bringing a big snow event as bitterly cold E,lys spread across the UK."

This is what I said on the 2nd of March.

"Looking at this mornings output a cold E,ly continues to look favourite, how cold is still very uncertain. Appears around the 11th March is when this could occur so only 24hrs later than I suggested many days ago."

http://forum.netweat...d-march-onward/

http://www.wetterzen...cs/Rtavn541.png

Unfortunately I cannot find the post when I referred to "Many days ago" but I do recall saying in late Feb that the 10th March was a significant date.

Fully expect this to be deleted mind you!

Edited March 9, 2013 by THE EYE IN THE SKY

[Frosty.]

even I have had enough of cold weather!

wow never thought I would hear you say that with potential for arctic outbreaks throughout march and april!!

Models are showing an end in sight to the cold weather, seems funny saying that since the cold air still hasn't arrived, feeling very cold on sun/mon and tues, then temps slowly recovering with any snow cover then melting and probably milder, wet and breezy by next weekend, so I expect today's meto 6-15 day update to be a lot less wintry than the last few days have indicated.

[Thundery wintry showers]

I can only think that the talk of "downgrades" stems from people looking at the charts at face value when they were a long way out, and then when they got closer to the time, looking more closely at the outputs for temperature and sunshine and being underwhelmed. The synoptic charts showing for Sunday/Monday are much the same as they were a few days ago and the cold blast is still showing 850hPa temps of -11 to -13C widespread.

The latest runs have been showing reduced chances of frontal snow over a wide area of the south but on the other side of the coin they have toned up the amount of convection that we get off the North Sea- Monday in particular is no longer looking as likely to be a mainly dry cloudy day as it did yesterday, except for a narrow zone to the north of the frontal belt like TEITS mentioned.

I don't think the upcoming week is likely to be particularly gloomy like Mushy suggested- the northerlies coming down on Tuesday should bring above-average sunshine in most parts of the country and just a scattering of wintry showers, mainly in the north-east. The end of the week looks increasingly like turning more unsettled with temperatures returning closer to normal values, particularly in the south. Anything particularly warm is out in FI, but at this time of year these northerly types do sometimes give way to a quick switch to warm southerlies, so it is worth keeping an eye on.

Edited March 9, 2013 by Thundery wintry showers

[bluearmy]

Have to say posts like this do irritate me.

I do not seek praise but I do like credit to be given when its deserved. Remember a while back the arguments with regards to the anomaly charts when some of us suggested cold weather was on its way and you disagreed.

Here is a comment I made on the 24th Feb!

"LP moving up from the S bringing a big snow event as bitterly cold E,lys spread across the UK."

This is what I said on the 2nd of March.

"Looking at this mornings output a cold E,ly continues to look favourite, how cold is still very uncertain. Appears around the 11th March is when this could occur so only 24hrs later than I suggested many days ago."

http://forum.netweat...d-march-onward/

http://www.wetterzen...cs/Rtavn541.png

Unfortunately I cannot find the post when I referred to "Many days ago" but I do recall saying in late Feb that the 10th March was a significant date.

Fully expect this to be deleted mind you!

dave - there are several posters on the forum that are appreciated for their insight. you are one of these. you do get some posts applauding your insight but that comes at a price and that price is being derided for getting it wrong (as per the block in december). i suggest you carry on as you are, and dont wait for cheers or boos. remain confident in your own ability - you don't need a pat on the back.

[Frosty.]

mild ?

less cold but not mild tom

i'm sure he means relatively mild, anything would be compared to the frigid air on mon/tues.

[BLAST FROM THE PAST]

I have to agree there , it's a bit cringe worthy to hear rogers dramatic take on events every time it's set to turn colder.

If roger can post evidence to back his estimations up then fair enough , but after the failed February from him it's falling on deaf ears I'm afraid mate. No offence Roger

UKMO shows potential for heavy snow and if the t48 - t72 came off then 20+cm is on the cards in elevated areas no problem. And if the following is a failed Feb then no one engaging in LRFs has a chance.

February. I am not even that confident of an arrival by 31 Jan looking at all data I would say it may be just creeping in about then but the core of the cold will be around middle of February lasting well into March with a sudden thaw and reversal at that point.

The cold hasn't been as impactive [the scurge of winter 12/13?]...but that's not a bad general outlook compared to what happened SSIB?

Anyway, as per usual the snowcasts are to be nowcasts...and its certainly looking likely to be more impactive than the beeb forecast a couple of days ago where the quote was the snow will NOT be problematic anywhere in the UK.....I think there are chances it will be?

BFTP

Edited March 9, 2013 by BLAST FROM THE PAST

[ukpaul]

Short ensembles looking good for here, average suggests up to six inches snow, op and control have much more than that.

Back where we were yesterday morning really, although the 'up to a foot' figures from yesterday seem to have shifted to Kent.

EDIT: For some reason I can't use the meteociel graph because of the extension. Sure I've done it before. Hmmm...

Edited March 9, 2013 by ukpaul

[Ian Brown]

erm, the charts that have been posted several times a day for the last ten days . yes there was an initial very cold noteable blast that was expected to last a day or two...thats not changed except that its looking like it wont be as severe as previously suggested.... some predicted a daytime max on -4c , ok those might have been reached IF those sypotics became reality...but as usual they didnt.

several of the recent runs predicted re-loads of he cold, predicting a protracted cold spell lasting over a week, very few have suggested a shorter cold spell. so as i see it, the cold chances going on this mornings runs have been significantly shortened.

my post wasnt miserable, it was realistic, most here are looking for either snow (as in a decent dumping) or warm spring sunshine, i dont think either 'side' will be happy with what is a rather gloomy, raw, wet, week ahead, with little in the way of settling snow for most, and precious little warm sunshine.

Mushy, you said last week how you were looking forward to the Atlantic return in the week just gone but since Wednesday all we have had is unremitting gloom and drizzle - whereas this week should see plenty of sunshine in many places especially from Tuesday onwards.

With regard to the snow events, we can see the PPN building now to the East and it will be interesting to see how the cold air undercuts the frontal this evening and tomorrow.

As for Monday, channel type lows are always fraught with difficulty for forecasters because until very late in the day it's very difficult to tell who will be in the milder air to the South, the snow band in the middle, and the dry cloudy area to the North.

[snowking]

The NAEFS warning system (based upon the MOGREPS solution the Met Office use) highlights the likely scenario here perfectly for me:

A few cms along Eastern coastal counties, with something more significant (strong signal for >5cms) across southern counties. This particular example is specifically for Monday, but I think it highlights the likely outcome through the Sunday-Tuesday period

SK

[peterf]

UKMO shows potential for heavy snow and if the t48 - t72 came off then 20+cm is on the cards in elevated areas no problem. And if the following is a failed Feb then no one engaging in LRFs has a chance.

The cold hasn't been as impactive [the scurge of winter 12/13?]...but that's not a bad general outlook compared to what happened SSIB?

Anyway, as per usual the snowcasts are to be nowcasts...and its certainly looking likely to be more impactive than the beeb forecast a couple of days ago where the quote was the snow will NOT be problematic anywhere in the UK.....I think there are chances it will be?

BFTP

it already is problomatic in Tow Law.

[seabreeze86]

Look how close the 510 Dam line gets to the east coast, very rarely does it come that close to the UK. The trough shud also help in terms of snow coming in from the north sea.

[Mair Snaw]

Rain turning to sleet here now in the peak district.. the odd wet flake of snow in there as well. still looking good for some parts of the south and the north. maybe something for Scotland too. good luck to you and happy lamp post watching to you all..

Edited March 9, 2013 by bigsnow

[Timmytour]

A great lovely bonus to a pretty good winter imo is what is coming up in the next few days. Well signposted by the likes ot TEITS, Steve Murr and, dare i say, the GFS!

Not sure in my location that i'll do that well for snow but it's looking like a few areas to the south and east and north will! Good luck to them all.

One thing that's amused me is Steve M's surge towards his 10,000th post. And i would say i have enjoyed reading all of them, agreed with most of them, and respected the ones i haven't agreed with. A fanastic poster and I think a fantastic achievement coming up.

Out of devilment i feel I have to point out that the 10,000 "eve" post was about what the 6z GFS was showing and not at all detrimental to the model at all!!!

Edited March 9, 2013 by Timmytour

[Snowman.]

Kent can recieve quite a blast from this as it slowly moves ENE sparking convection as it does so looking at the charts a good 6-9 Hours of heavy snow.

Edited March 9, 2013 by SN0WM4N

[Geordiesnow]

erm, the charts that have been posted several times a day for the last ten days . yes there was an initial very cold noteable blast that was expected to last a day or two...thats not changed except that its looking like it wont be as severe as previously suggested.... some predicted a daytime max on -4c , ok those might have been reached IF those sypotics became reality...but as usual they didnt.

my post wasnt miserable, it was realistic, most here are looking for either snow (as in a decent dumping) or warm spring sunshine, i dont think either 'side' will be happy with what is a rather gloomy, raw, wet, week ahead, with little in the way of settling snow for most, and precious little warm sunshine.

With respect, this cold spell has NOT downgraded what so ever, infact the uppers may even tone up ever so slightly for Sunday into Monday with the -15hpa not a million miles away at all, temperatures are going to be way below average and in any showers, temperatures will struggle to get above 0C. Nighttime temperatures into next week could also be quite low for the time of year.

I also don't agree with your prediction that the week ahead will be dull, especially once the Northerly flow comes in although inland areas will probably be slightly cloudier than say if this set up occured during January as the stronger sun and cold air over land forms convective cloud and could squeeze out a few showers in places.

As a weather enthusiast, this spell of weather interests me, its not unusual for a cold shot to occur in March but the strength of the cold is unusual. Should be an interesting few days weather wise.

[Yorkshiresnows]

erm, the charts that have been posted several times a day for the last ten days . yes there was an initial very cold noteable blast that was expected to last a day or two...thats not changed except that its looking like it wont be as severe as previously suggested.... some predicted a daytime max on -4c , ok those might have been reached IF those sypotics became reality...but as usual they didnt.

several of the recent runs predicted re-loads of he cold, predicting a protracted cold spell lasting over a week, very few have suggested a shorter cold spell. so as i see it, the cold chances going on this mornings runs have been significantly shortened.

my post wasnt miserable, it was realistic, most here are looking for either snow (as in a decent dumping) or warm spring sunshine, i dont think either 'side' will be happy with what is a rather gloomy, raw, wet, week ahead, with little in the way of settling snow for most, and precious little warm sunshine.

Well maybe I am mistaken but I look at the charts and see. -14 uppers across the whole country Monday into Tuesday. Heavy convective snow showers with the possibility of frontal snow skimming the South and South East, dew points below freezing .......that would be settling snow even though we are in March. Possible notable accumulations Sunday night .... its a developing situation.

Agree that after that its is likely to be cold and pretty miserable until at least later in the week ....... where did anybody say it was going to be -4 all day ..... from what I read the majority were quite rightly quoting two possible ice days ...... which looks a close call for Monday into Tuesday.

I'm happy with that. Something very rare in March and quite exciting !

Y.S

[shedhead]

Despite edging ever closer to a possible snow event in the south, detail remains frustratingly elusive, with the margin for error becoming smaller and of increasing concern each and every run. Any county that doesn't immediately border the English Channel now looks very unlikely to see any frontal snow and even those areas 20 miles inland might struggle to see much more than a dusting. Right on the coastal fringe sleet also looks rather more likely than snow, so we're probably looking at a very narrow swathe of countryside just inland from the Channel as being best placed (or perhaps worst depending on your viewpoint) to pick up some decent snowfall, with any elevation clearly helping the cause. Areas of south and east Dartmoor, Bodmin Moor and the hillier parts of SE Devon and Dorset are my call atm, but no doubt the potential remains for much larger parts of the south to get pasted....equally we could all miss out altogether.

[Frosty.]

The Gfs 06z shows a monster greenland high in FI but no help to us because the pattern seems to be becoming more west based with the uk on the road back to normal early spring after the short burst of potent scandi cold, from midweek the temps are recovering and that spoiler low to the nw appears to bring down the curtain on our cold snap later next week, unless the usual gfs eastward bias is in action again and there could be a chance of holding on to the cold air for longer.

[-uksnow-]

The warning for the south has been updated as of 1136 today:

"

A spell of sleet and snow is expected, starting in the early hours of Monday morning in southwest England, and affecting southern England more widely by the end of the morning. Snow will be accompanied by a strong easterly wind which will accentuate the very cold feel. Accumulations of 2-4 cm of snow could occur quite widely over southern counties, with a risk of 5-10 cm over Dartmoor.

The public are advised to be aware of the risk of localised disruption to travel. "

[Summer Sun]

A chart for the long suffering Mushy.

http://www.wetterzen.../Rtavn32417.png

Im sure Nick Sussex would be delighted of temps of 25C across France.

And me!

Coldies need to make the most of the next 48 hours by Tuesday the bitterly cold temperatures look like easing ever so slightly to around 4 to 6c

By Wednesday the change to milder air is underway in the southwest with highs up to 7c 5 to 6c in the east widely

But its Thursday when we see the milder air UK wide 7c widely 8c in the south west by this point only Scotland stays colder

By Friday we are back in double figures for the south coast 7 to 8c widely again only Scotland remains cold with 2 to 4c widely here

Into Saturday and most of the south is in double figures northern England to the midlands has highs of 6 to 8c once again Scotland remains the coldest with highs of just 4c

So if your a coldie my advice is pack your bags and head upto Scotland other wise for England and wales we will see a recovery of temperatures this week with Sunday and Monday the coldest period before double figure temperatures look like making a welcome return towards the end of the week which is to be expected after all this cold can't realistically last long this time of year

Edited March 9, 2013 by Gavin.