Model runs-late february to end of march

nacho libre

It's going to be a great weekend for snow lovers in the north, north east and the east of England. Damn that high pressure out in the Atlantic:mad:

Paddy.1

Potential for northern blocking still there in latest ECM 00z run. At 168hrs (Friday next):



Some dream synoptics occur in the run after this:
ECM 192hrs
ECM 216hrs
ECM 240hrs

Note the intense high building over Newfoundland and Baffin at 240hrs. Always an precursor, I think, to a cold snap this side of Atantic.

Of course it is all painfully FI at this stage, but I hope to God this pattern comes to fruitation, and not annihilated in future runs.




Run:

patneve

could be interesting! -5,-6 at 850 with decent precipitation....rain sleet or snow?probably sleet or rain at lower levels, but mountains could get a decent covering!

ninebeanrows

Looking great for much of mainland Britain tomorrow and on Sunday.

Out here in Ireland it looks too marginal, the further east the better but still limited prospects.

Perhaps some temporary sleet when the feature moves south on Sunday morning...

Looks like the same feature could bring upto or over 15cm's of snow to parts of England.... for those viewing forums such as Netweather.... be prepared for a painful collection of pictures

Snowbie

The warm sector indeeds floods all of Ireland with Wales the same too.
If only it had stayed off the western coast then something interesting would have happened here in the majority of the country though still marginal for coastal areas.

The cold air when 850temps at -7 will hit a line from Dublin to Galway around 1800.
The significant part of this snap will just be a frost event and not good for plants or gardeners away from the north.

*There is always the chance that the high out west will retrograde west and allow the feature to pass off the west but this is highly unlikely now but with still a few runs to follow anything is possible.









*Wishful thinking.

revr

Well the low has moved further West increasing the chances for a snow event for Eastern areas. West Scotland will get hammered.


http://85.214.49.20/wz/pics/brack0a.gif

Hard to say whats going to come out of those features with a high degree of certainty.
I'd be fairly confident that snow ploughs won't be needed at lower levels...Though inland and above 500ft,there is a much higher chance of snow I think.
Down at lower levels,theres likely to be some show and hail at times in the showers over the coming days because the dp's are quite low and theres increasingly a lot more polar maratime air in the mix as opposed to the more mixed air in the organised systems over the w/end.
But as usual these things have the ability to surprise.

darkman2

I think the most low lying areas can expect tomorrow night is sleet. Once the upper temps go above -5 thats that for snow. Higher levels will get snow tomorrow night though. Of course this will still come down to a now cast and anything is possible but im not backing snow away from high ground for now.

Snowbie

Deleted User wrote: »

Hard to say whats going to come out of those features with a high degree of certainty.

Likely scenario,
Temps and dewpoits will remain low even under the approaching altostratus of the warm front giving some a false pretense of snow is imminent.Then as the warm front closes in dp will start to rise gradually with a stagnant air temp remaining low. So now you turn to the wet bulb temps which need to be at or below 2c for a chance of transient snow, albeit wet at that.

Though inland and above 500ft,there is a much higher chance of snow I think.

Yep chances i'd say are higher than this time yesterday with the fax chart revr linked to for mtns.
The warm sector has 850mb temps of -4c(from 12z) over much of the country as by then should be an occlusion.
So the chances of the cold air undercutting in the wake are increased as -7c 850s digs back in to give some snow as it clears through.

ATM, there is nothing i can see that will give snow at lower levels even inland, but mountains are at higher risk, more so than yesterday.
Only hope is the fax chart does have the feature a tad more west but still too marginal for snow at low levels.

What will 18z deliver:rolleyes:

kerry1960

Snowbie wrote: »

Likely scenario,
Temps and dewpoits will remain low even under the approaching altostratus of the warm front giving some a false pretense of snow is imminent.Then as the warm front closes in dp will start to rise gradually with a stagnant air temp remaining low. So now you turn to the wet bulb temps which need to be at or below 2c for a chance of transient snow, albeit wet at that.
Yep chances i'd say are higher than this time yesterday with the fax chart revr linked to for mtns.
The warm sector has 850mb temps of -4c(from 12z) over much of the country as by then should be an occlusion.
So the chances of the cold air undercutting in the wake are increased as -7c 850s digs back in to give some snow as it clears through.

ATM, there is nothing i can see that will give snow at lower levels even inland, but mountains are at higher risk, more so than yesterday.
Only hope is the fax chart does have the feature a tad more west but still too marginal for snow at low levels.

What will 18z deliver:rolleyes:

Any chance of an hour or so of some wet snow for the higher ground in the SW (1000ft+) from the back edge of this weather front ??

Supercell

kerry1960 wrote: »

Any chance of an hour or so of some wet snow for the higher ground in the SW (1000ft+) from the back edge of this weather front ??

Yep, you might indeed, whether it settles is another matter.
I'm expecting snow tomorrow night but of the very wet variety. Snowline may be pretty close, even down to 300m, going to be an interesting night for sure.
Have to say, I've had a LOT more snow events this year than last year, pity they have all been of the crap variety!

Snowbie

kerry1960 wrote: »

Any chance of an hour or so of some wet snow for the higher ground in the SW (1000ft+) from the back edge of this weather front ??

Iniatially, there be more of a chance of snow at 1000' in the east than 1000' in the south west as its progged to be less cold in your part of the world than here due to slightly higher 850mb temps where you are at the passage of the front.
Almost everywhere is at risk at the back of the front where the rain/sleet turns to snow before it clears(in theory)
It is called a nowcast event or tomorrow's 18z to finalise where exactly the colder temps (850mb) are going to be before and after.

kerry1960

Snowbie wrote: »

Iniatially, there be more of a chance of snow at 1000' in the east than 1000' in the south west as its progged to be less cold in your part of the world than here due to slightly higher 850mb temps where you are at the passage of the front.
Almost everywhere is at risk at the back of the front where the rain/sleet turns to snow before it clears(in theory)
It is called a nowcast event or tomorrow's 18z to finalise where exactly the colder temps (850mb) are going to be before and after.

Ah well
i don't really expect anything much around here anyway:mad:, hope the leinster contingent have something worth posting about .


(Me and daughter available for snowman construction duties at short notice,anywhere ,:D

On a slightly differant note that windstorm from 10 march had some fair poison in it , mature hedging/shrubs/ small trees around here have been burned black brown




,

Snowbie

6z is a terrible run for snow even to higher ground here. Height of 0c isotherm around 600meters on this run and gets higher through the night.

As per usual the UK is going to get all the fun, with last night snow showers persisting over the majority of eastern UK, next there will be several hours of frontal snow overnight for them.

nacho libre

from met.ie:
Rain spreading southwards across the country later this evening and tonight, falling as sleet for a time in parts of Ulster and north Connacht and on hills. Lowest temperatures zero to 3 degrees with moderate northwest winds backing northwest to west and gradually freshening. Ground frost forming in some southern areas for a time and in northern areas as the rain or sleet clears.

Paddy.1

nacho libre wrote: »

from met.ie:
Rain spreading southwards across the country later this evening and tonight, falling as sleet for a time in parts of Ulster and north Connacht and on hills. Lowest temperatures zero to 3 degrees with moderate northwest winds backing northwest to west and gradually freshening. Ground frost forming in some southern areas for a time and in northern areas as the rain or sleet clears.

Nothing for South Connacht then...? Ah well, just another notch on my bedpost of thawts in this b&&&&x of a season. My eyes still on FI ECM. Potential, sham.

nacho libre

Paddy.1 wrote: »

Nothing for South Connacht then...? Ah well, just another notch on my bedpost of thawts in this b&&&&x of a season. My eyes still on FI ECM. Potential, sham.

I'm afraid i can't share your optimism!
I've given up at this stage. it's just been one disappointment after another this Winter and Spring

Gonzo

winters well and truly over here in Ireland, wait till next December, this coolish spell is just annoying, i wish summer would just start now with some mild feeling warm sunny days.

Supercell

I see the 16:00 taf for Dublin airport has changed from earlier when they were predicting sleet tonight to just light rain from 2AM - 6AM :-

EIDW 221600Z 230024 29015KT 9999 SCT017 BKN025
BECMG 0003 29020G30KT
TEMPO 0206 5000 -RA SCT008 BKN012
BECMG 0508 32020G32KT
BECMG 0912 35018G30KT
BECMG 2124 32015KT

Game over it would seem for us here, ohh well we can watch the whoops of joy from the brits on their various forums..

Danno

Longfield wrote: »

Game over it would seem for us here, ohh well we can watch the whoops of joy from the brits on their various forums..

Christmas 2004 V Easter 2008 - Our snow was better!

Supercell

Danno wrote: »

Christmas 2004 V Easter 2008 - Our snow was better!

Or Snow in County Louth, January 3rd 2008 was pretty fantastic too, hard to believe that was this year.

Or Meath getting in the sneachta action too

Louth and Meath > UK ..not often Louth and Meath people get to say that

Supercell

Interesting trends :-

Temperature heading in the right direction:-



Dewpoint however:-



Conclusion, going to be frustratingly close snow miss tonight.

Gonzo

Longfield wrote: »

Or Snow in County Louth, January 3rd 2008 was pretty fantastic too, hard to believe that was this year.

Or Meath getting in the sneachta action too

Louth and Meath > UK ..not often Louth and Meath people get to say that

it was amazing alright, shame it lasted so short because it was a proper decent 1980s style dumping and a few extra hours of that easterly would have given us 8 or 9 inchs maybe more. There was no stopping those snow showers untill the wind shifted direction and the showers dissapeared. If that had continued all night and nto the following day who knows how much snow we coudl have ended up with. If it wasnt for those few lucky hours were the conditions were perfect for snow, this would have gone down in my history as the worst winter of all time but for me it was saved because of those magical few hours.

Ah ya might have some wet snow at least up there longfield.
It's quite cloudy here which I presume is the high cloud ahead of the front-yet We've a temp of 4c down here and a circa -3c dewpoint (it is fluctuating though)

My experience tells me thats enough (almost) for rainy sleet on low ground and wet snow where you are with perhaps dry snow at 800ft and higher.
The dewpoint wouldnt want to go much above -2c or the wet snow line will probably rise to above 1000ft.
Unfortunately the air coming down will be mixed so a rise to 0c dp's and above eventually at sea level is inevitable I think making any rainy sleet be rain here and rising that snow line back above 1000ft-aided and abetted of course by the rising temp in the air aloft.

Lugnaquilla had a layer of snow on it above 2500ft approx from yesterdays showers all day today by the way (I doubts todays snow showers up there added any as they were light).
I expect the entire mountain and any around it above 1500ft (including croghan and obviously kippure) to have more than a few inches by tomorrow morning

Supercell

I'm not good mentally converting feet to metres but i think your saying about 500 metres upwards may see some snow out of this tonight?
I think you might be right maybe even a little higher for decent snow cover (circa 600 metres), i'm going for a drive tomorrow anyhow and plan on going snap happy in any lying snow I encounter.

Supercell

Temp fall seems to have stopped, currently 2.9°C, dewpoint still rising slowly.

Ohh well, its going to be rain.

Well I'd expect snow at times albeit mostly wet stuff where you are,given you are circa 600ft asl and a good 10 miles inland ish.
Drier snow with artictree for a time before the snow line retreats to above 1000ft or so.

1000ft is approximately 305 metres by the way.
It can often depend on the surrounding terrain too.
For instance if you are within a mile or two of ground above 1000ft or so if thats where the snow line should be, and you are a decent bit inland,you can sometimes borrow the high grounds snow, bringing the snow level down by a few hundred feet.
The same shower/system/band travelling over that ground a few hundred feet lower down in an area further away and not as proximate to the higher ground would be getting unluckilythe sleety rain.

darkman2

Dewpoints will rise to between 2 and 5C after midnight - thats too high even for high level snow below about 800m's. Id be supprised if anyone saw a flake tonight. All so different just 100 miles to our East. The setup is not even marginal - its completely out of the question for snow tonight.

Lol

ninebeanrows

darkman2 wrote: »

Dewpoints will rise to between 2 and 5C after midnight - thats too high even for high level snow below about 800m's. Id be supprised if anyone saw a flake tonight. All so different just 100 miles to our East. The setup is not even marginal - its completely out of the question for snow tonight.

850hpa temperatures of around -5c, temperatures of 2-4c and moderate precipitation falling.

I reckon 4 inches from 400 metres up with slushy stuff from as low as 200metre up.