Cold Spell - Feb 7th to 13th 2021 - Chat

JanuarySnowstor

Poor enough forecasts from Met Eireann this evening.
Not even a mention of snow risk along the South Coast.
Temps of 3C look very optimistic to me though I guess under sunshine in the West maybe..

Calibos

Calibos wrote: »

...Yet he fears those Shadows as much as me in Bray 40km to his North

We can literally see Wales in good visibility
Not enough water at all
I've no fear of the Isle of man here as regards fetch at all,that's probably more NNE from here

Humberto Salazar

The Brits will be buried in drifts while we look out at the greenery. That's the way I remember it in the 80s. When we got easterlies it needed really deep cold to make it here. Like 82 and 87. But most times we only got a glimpse.

JanuarySnowstor

JanuarySnowstor wrote: »

Poor enough forecasts from Met Eireann this evening.
Not even a mention of snow risk along the South Coast.
Temps of 3C look very optimistic to me though I guess under sunshine in the West maybe..

I don't think that's fair
Those forecasts are time limited
They have to get the next 48hrs in,in detail and by the time that's done there's only 30 seconds for an overview of the outlook
They'll mention it inside 48hrs and will also be more detailed about the temps

pad199207

Can definitely sense that the spirits are lower this evening and rightly so. Yeah it’s all good to see the snow start to fall and accumulate it really is, but when you know it’s all going to be gone in a day or two from the Atlantic pushing in it’s kind of heartbreaking.

Really hoping for further upgraded but I’m not holding out for much from now on.

KingJeremy

Just a break from the relentless rain and grey is all I’m hoping for. The place is like a quagmire. Can’t even get out for a decent walk without your wellies

mcburns07

pad199207 wrote: »

Can definitely sense that the spirits are lower this evening and rightly so. Yeah it’s all good to see the snow start to fall and accumulate it really is, but when you know it’s all going to be gone in a day or two from the Atlantic pushing in it’s kind of heartbreaking.

Really hoping for further upgraded but I’m not holding out for much from now on.

Haven't looked at the charts this evening, is the Atlantic a certainty to come piling in on Thurs?

pad199207

mcburns07 wrote: »

Haven't looked at the charts this evening, is the Atlantic a certainty to come piling in on Thurs?

Well when the ECM and the GFS are starting to agree it’s a hard thing to break.

Oneiric 3

Calibos wrote: »

East Counties affected by IOM or Wales Shadow.

Louth - 129,000
Meath - 195,000
Dublin - 1,345,000
Kildare - 222,000
Wicklow - 142,000
Wexford - 149,000

2,182,000 People

ie. Nearly half the entire population of the Country

It's still a tiny part of the country. Doesn't matter how many people live there, and not really sure how more people in a place makes the individual experience of anything that occurs in it more profound.

Chalkitdown147

Calibos wrote: »

East Counties affected by IOM or Wales Shadow.

Louth - 129,000
Meath - 195,000
Dublin - 1,345,000
Kildare - 222,000
Wicklow - 142,000
Wexford - 149,000

2,182,000 People

ie. Nearly half the entire population of the Country

D15 right on the Meath border and we got a good bit of snow 2018, albeit from a frontal Emma mostly but i remember relentless streamers and one stage

Inmate2020

Reading so much about Iom shadows etc . It’s pot luck . We got plastered in Bray 2018/2010 . 5 miles down the road nothing . It’s the luck of the draw . If a cloud is overhead and dumps snow , happy days - the same cloud may not dump down the road . So cross the fingers hope for the best ❄️

Muahahaha

If it is to snow in east Leinster what day is it expected? Trying to figure out whether to stock up when shopping tomorrow. And how many days is this cold front expected to last

Rebelbrowser

mcburns07 wrote: »

Haven't looked at the charts this evening, is the Atlantic a certainty to come piling in on Thurs?

In a word, no. Maybe 70/30 in favour of that outcome. But if we have the aforesaid 2 or 3 days of lying snow by then, how bad!

Squidvicious

Oneiric 3 wrote: »

It's still a tiny part of the country. Doesn't matter how many people live there, and not really sure how more people in a place makes the individual experience of anything that occurs in it more profound.

Hardly tiny. And you could add parts of Co. Waterford, Co. Kilkenny, Co. Carlow, and even Co. Laois and Co. Offaly who will see snow from showers originating in tge Irish Sea if conditions are right.

Calibos

Oneiric 3 wrote: »

It's still a tiny part of the country. Doesn't matter how many people live there, and not really sure how more people in a place makes the individual experience of anything that occurs in it more profound.

You seemed to be expressing consternation about such a big deal made about IOM shadow for such a tiny part of the country implying you don't understand why so many of us fret about it.....its because there are so many of us in the aforementioned counties that can be affected by it. ie. 2.2 million of us. ie if nearly 50% of the posters on this forum are from those Eastern counties theres bound to be a lot of people worried about Wind direction and the IOM Shadow and posting about. So why are you surprised its talked about so much. The fact that it is only about 20% of the land area of the country is neither here nor there.

Humberto Salazar

derekon wrote: »

Always the bridesmaid, never the bride! Your enthusiasm is infectious. It hasn’t even started and you’ve written it off!

D

I'm not writing off that somewhere will see some snowfall. But for every ten easterly blasts in winter we only get something 2 or 3 times because of our westerly position. Simple facts. When it works, it's great. Maybe we will get something over the three day window.

Donegal Ken

count yourself lucky if you see snow there are many in the west which will see none early next week. The people in the west, northwest and north are well use to snow only lasting a day or two. Long way between now and the weekend and much can change. Could be worse with us not seen any sort of set up like this over the winter at all. As for Met Éireann don't expect any big forecast updates from them until the weekend when we will see the first of the snow/ice warnings and low temperature warnings most likely issued on Sunday with a advisory possibly issued by Friday.

Oneiric 3

Calibos wrote: »

You seemed to be expressing consternation about such a big deal made about IOM shadow for such a tiny part of the country implying you don't understand why so many of us fret about it.....its because there are so many of us in the aforementioned counties that can be affected by it. ie. 2.2 million of us. ie if nearly 50% of the posters on this forum are from those Eastern counties theres bound to be a lot of people worried about Wind direction and the IOM Shadow and posting about. So why are you surprised its talked about so much. The fact that is 15% of the land area of the country is neither here nor there.

Can I start talking about the 'Ireland shadow' then? Fellow westerners, jump in and let's make this a thing!

In all seriousness, I doubt even 0.01% of that 2 mil plus population in the east gives a flying .... about the 'IoM shadow'.

Nqp15hhu

JanuarySnowstor wrote: »

Poor enough forecasts from Met Eireann this evening.
Not even a mention of snow risk along the South Coast.
Temps of 3C look very optimistic to me though I guess under sunshine in the West maybe..

Freezing levels are 200-300 metres each day. So it will vary on wind strength and cloud cover.

With the cold spell about a week or two ago, I had a few days of 2c highs under sunshine and -6c hPa.

redsteveireland

Oneiric 3 wrote: »

Can I start talking about the 'Ireland shadow' then? Fellow westerners, jump in and let's make this a thing!

In all seriousness, I doubt even 0.01% of that 2 mil plus population in the east gives a flying .... about the 'IoM shadow'.

I have the Connemara Mountains shadow to deal with from a North westerly

PauloMN

Has there been a downgrade in the forecast for snow next Tue/Wed/Thur? I checked Met.ie and yr.no earlier, and both were showing the same, with a fair bit of snow across the 3 days. Now both are showing pretty much nothing, other than cloud/rain, maybe a bit of sleet. Am in Meath.

John.Icy

GFS 18z upgrade out to +126.

18z



12z equivalent.

Nqp15hhu

I still think we could have a week of cold weather I.e <3c highs.

Don’t see the cold breaking up that quickly considering how far into the Atlantic it spreads

Gonzo

Mod Note: most of the posts over the past few hours have nothing to do with this cold spell. Posts relating to bread, covid, random posts, locations etc removed. Nobody wants to read pages of random posts that are not helpful in any way to the topic. Only post if it is in relation to the upcoming cold spell with helpful information and model watching/data.

squarecircles

18z another pigs ear for frontal snow in the west.

Kermit.de.frog

Don't tell those Cork lads

TTLF

the 18z is an upgrade of sorts. It's just really a matter of how it'll turn out on the day and lots can change in the mean time, seeing the differences of 12z/18z there show this. Better not to get too wrapped up on all runs for now I guess. 18z's low was vastly different to the 12z being more westward although mild gets in at the end, but who knows really.

Lots to change... onto tomorrow's runs! :pac:

Cork2021

Kermit.de.frog wrote: »

Don't tell those Cork lads

Happy emoji!

Calibos

Oneiric 3 wrote: »

Can I start talking about the 'Ireland shadow' then? Fellow westerners, jump in and let's make this a thing!

In all seriousness, I doubt even 0.01% of that 2 mil plus population in the east gives a flying .... about the 'IoM shadow'.

You are just being painfully literal to win an argument at this stage.

Of course I don't think any measureable fraction of that 2.2 million are worrying about the IOM Shadow. However that 20% land area of the Country holds nearly 50% of the population at 2.2 million people. Now if we assume that the boards Weather forums 100 most regular posters are split along the same population distribution lines then it means nearly 50 of the top 100 posters would be from those counties affected and thus interested in the IOM Shadow.

Hence.....is it any wonder so many of us regulars here talk about it.

Mimon

Sure half the craic in a potential snowmegeddon is the chase and people who normally never go near the weather forum turning up and giving their tuppence worth.

I agree bread joke has been done to death :pac:

Funsterdelux

Kermit.de.frog wrote: »

Don't tell those Cork lads

Sacrebleu!

Squidvicious

Kermit.de.frog wrote: »

Don't tell those Cork lads

How far north east is that likely to get(from a non Cork lad😉)

Tyrone212

Gfs follows Ecm in showing paltry limited accumulations from showers next week. Slim pickings, American time.

https://weather.us/model-charts/standard/ireland/snow-depth-in/20210209-2100z.html

https://weather.us/model-charts/standard/ireland/snow-depth-in/20210210-2100z.html

lucernarian

Tyrone212 wrote: »

Gfs follows Ecm in showing paltry limited accumulations from showers next week. Slim pickings, American time.

https://weather.us/model-charts/standard/ireland/snow-depth-in/20210209-2100z.html

https://weather.us/model-charts/standard/ireland/snow-depth-in/20210210-2100z.html

It showed the same in past situations. Parts of Louth, Dublin and Wicklow reached over 40cm of snow over 3 days in November/December 2010 even though little was forecast by the global models. The short term, high resolution models were better, but they still underestimated the precipitation that fell

Rebelbrowser

Tyrone212 wrote: »

Gfs follows Ecm in showing paltry limited accumulations from showers next week. Slim pickings, American time.

https://weather.us/model-charts/standard/ireland/snow-depth-in/20210209-2100z.html

https://weather.us/model-charts/standard/ireland/snow-depth-in/20210210-2100z.html

Always the way from streamers. They showed v little precipitation in 2018 and 2010 too. Doesn't mean they won't be right this time of course.

More generally, just looking at the Icon and the low it has passing through on Tuesday, that seems like crazy model variation at this remove for 5 days time.

Tyrone212

In my experience the models usually over cook snow totals from far out more often than they don't.

JanuarySnowstor

I would think the Icon low for Tuesday isn't going to happen so best to forget about it. GFS looks good though for quite a few coastal snow showers.

Re long term this cold spell will surely put up a fight so I fully expect at least Thursday to remain bitter.
We won't get much sleep will we, yet another 4am start for most of us lol

sryanbruen

Didn't know whether to post this in FI or this 'event' thread. Interesting to hear that the in-house UK Met Office MOGREPS are showing the cold being prolonged and the lows to not successfully undercut the blocking although difficult to tell the north positioning of them with no synoptics available publicly.

Can't say I see such a "dense" anticyclonic block in the high latitudes as compared to the years named in the model output, looks all fragile to me. I still remain skeptical about this entire thing until I see something more exciting arise, Tuesday looks best day as of now to me but not expecting much.

We know what model runs have been like throughout this polarcoaster though.

https://twitter.com/EssexWeather/status/1357458451308417024

Nqp15hhu

I agree. This looks to be quite an intense pool of cold air that flows past the western coast 300-500 miles.

I don’t see that breaking down that quickly. Especially considering that somewhat milder air put up a bit of a fight up here this week.

Gaoth Laidir

About sea-effect showers, the main factors affecting the sea fetch required are both the temperature differential between the sea and 850 hPa and the 850-hPa windspeed and directional shear up to 700 hPa.

With the >13-degree difference a given, the optimum 850-hPa windspeed for organised bands is around 20 knots. Higher speeds require more of a sea fetch, but as there will be more like an 18-degree temperature difference and 850 hPa will be lower than the standard 1.5 km that required fetch will be reduced again. Directional shear between 850 and 700 hPa should be 30 degrees or less to keep some sort of organisation.

The GFS sounding for the middle of the Irish Sea shows no directional shear but around 30 knots easterly. Slightly high, but the large temperature difference should offset some of the limiting effect of that. It shows convection to around 700-650 hPa for a surface parcel warmer than that shown (allowing for warming nearer to Ireland), but the further north the lower the mid-level temperature and the deeper the convection.

At that particular point in time showers should be moving westwards and confined to the Irish Sea north of Anglesea, due to the easterly steering flow limiting fetch south of that. Dublin to Louth would be favoured in this scenario, with the stronger flow allowing showers to make it further inland. Here in north Kildare could be a good spot.

Tyrone212

Tyrone212 wrote: »

In my experience the models usually over cook snow totals from far out more often than they don't.

But the people you are replying to gave you examples, in a similar set up to this one where the opposite was true.

Edit.

And GL has a good post as well.

I was wondering if the sea might be a bit too cold compared to December 2010, this is probably when it is at its coldest.

nacho libre

The thing is Mogrep could be right, but that could mean much of England holds on to the cold while we go mild. There is scatter on the GFS suite but I think it is unlikely the op runs will upgrade to the extent that lows will trend far enough south in the next couple of days to prolong the cold for us.

Tyrone212

[Deleted User] wrote: »

But the people you are replying to gave you examples, in a similar set up to this one where the opposite was true.

Edit.

And GL has a good post as well.

I was wondering if the sea might be a bit too cold compared to December 2010, this is probably when it is at its coldest.

Well I believe I said more times than not they overcook totals from far out. I didn't say they always do. I didn't say there were zero examples of the opposite of happening. Not sure how it was so difficult to deduce that.

JCX BXC

Christ my eyes are bleeding from this thread. I'm sorry I read over the last 15 pages. Why do people reply to those who are clearly trolling and do so every event?

I was quite surprised to hear the blatant ramping by Evelyn on the radio today, it's very early to be discussing significant snowfall at the end of next week, it's 6/7/8 days away.

Can't imagine the West Coast will see much snow, charts done seem to think much and to be honest it's much too early to consider the frontal snow possibility, that will likely come down to fine tuning.

nacho libre

nacho libre wrote: »

The thing is Mogrep could be right, but that could mean much of England holds on to the cold while we go mild. There is scatter on the GFS suite but I think it is unlikely the op runs will upgrade to the extent that lows will trend far enough south in the next couple of days to prolong the cold for us.

Well if it doesn’t snow here the low has to bring mild air over southern England unless it directly comes in due West. Perhaps.

Some guy on NW said the difference in temps is 10 degrees between ensembles at his location. I reckon it’s to play for. Good model watching anyway.

Remember the gfs was expecting mild early next week just a few days ago.

Tyrone212

Tyrone212 wrote: »

Well I believe I said more times than not they overcook totals from far out. I didn't say they always do. I didn't say there were zero examples of the opposite of happening. Not sure how it was so difficult to deduce that.

You said more often than not. Which isn’t true of streamers and the most recent and memorable events which are similar to next week.

Tyrone212

[Deleted User] wrote: »

You said more often than not. Which isn’t true of streamers and the most recent and memorable events which are similar to next week.

More times than not, more often than not means the same thing. Well you're wrong. But sure they'll be 10 feet snow outside your house next week if that's what you want to hear.

The One Doctor

Tyrone212 wrote: »

More times than not, more often than not means the same thing. Well you're wrong. But sure they'll be 10 feet snow outside your house next week if that's what you want to hear.

You sound very like that other NI guy who complains all the time. Are you related?

Tyrone212

The One Doctor wrote: »

You sound very like that other NI guy who complains all the time. Are you related?

I'm not complaining. I posted the snow accumulations charts from the ecm and gfs for next week both of which are currently poor. Thats a fact. Complaining about said charts led to this discussion.

It can still improve but they usually overcook snow accumulations projections from far out. Some people are just to childish too accept what the charts are currently showing. It'll all end in tears if they turn out to be correct. I take it you're another one? Are you related to the other southern guy who's always complaining? You sound like him.

JCX BXC

Not even overcook, I find those snowfall charts are often very inaccurate. They may be of some use in a very close time period, anything last 2/3 days I wouldn't even bother looking. The smallest differences between runs completely changes what they show.