Snow watch until Sunday 24th (N,W,SW most at risk)

Kermit.de.frog

Thread for flooding potential Connaught, North Leinster, South Ulster through Monday night/Tuesday/first half of Wednesday.

Heavy snow potential second half of Wednesday particularly Leinster and Munster. Much colder by evening.

Surprised a thread wasn't started for the flood potential. Will update this OP in the morning.

Interesting 48 hours to come from tonight to say the least.

Rock Lesnar

Flooding, great

redsteveireland

Kermit.de.frog wrote: »

...

Surprised a thread wasn't started for the flood potential. Will update this OP in the morning.

Interesting 48 hours to come from tonight to say the least.

All too pre-occupied with the Snow-casting!

Gaoth Laidir

Can't see any real snow potential with this at all, apart from mountains. There's just no cold out to our north. Sounding from as far north as Iceland and Jan Mayen, from where Wednesday's northerly will come, just don't give much hope.

https://meteologix.com/ie/radiosonde-values/83-w-662-n/temperature/20210118-0000z.html

TheMilkyPirate

6z showing a 6-7 hour window for snow for the southeast. Can't imagine it will amount to much but interesting all the same.

Gaoth Laidir

Gaoth Laidir wrote: »

Can't see any real snow potential with this at all, apart from mountains. There's just no cold out to our north. Sounding from as far north as Iceland and Jan Mayen, from where Wednesday's northerly will come, just don't give much hope.

https://meteologix.com/ie/radiosonde-values/83-w-662-n/temperature/20210118-0000z.html

Bbc 24 forecast for what it's worth has it turning to snow in kildare wenesday afternoon which would be meteogroup's opinion
They're blending a few models presumably

KingdomRushed

The 6Z GFS (parallel) has much more prolonged snowfall modelled for wednesday for much of eastern Ireland than the actual GFS run for same period. How do people rate that model in the short term

esposito

KingdomRushed wrote: »

The 6Z GFS (parallel) has much more prolonged snowfall modelled for wednesday for much of eastern Ireland than the actual GFS run for same period. How do people rate that model in the short term

Very good question kingdom. Don’t you just wish there was one GFS model to ease the tension/uncertainty.

Isn’t the parallel supposed to replace the old GFS very soon. If it is then surely it has to be taken seriously?

nacho libre

esposito wrote: »

Very good question kingdom. Don’t you just wish there was one GFS model to ease the tension/uncertainty.

Isn’t the parallel supposed to replace the old GFS very soon. If it is then surely it has to be taken seriously?

I've read of late it's second only to the ECM out to day 5, but is quite poor beyond that.

blindsider

AuntySnow wrote: »

Bbc 24 forecast for what it's worth has it turning to snow in kildare wenesday afternoon which would be meteogroup's opinion
They're blending a few models presumably

https://en.wikipedia.org/wiki/BBC_Weather

BBC WEather supplied by Meteogroup since 2018....I missed that

Danno

This is the GFS PARA at 54hrs. Shows 5hrs of moderate to heavy snow for inland Munster and South and Central Leinster but those along the immediate east coast may not get as much until a couple of hours later (well into the afternoon) but hangs around the east coast counties for a good few hours well into night.

Danno

Again the GFS PARA here - this time at 7pm Wednesday evening showing good accumulations across the east and south midlands, up to 11cm on the western side of the Wicklow Mtns! Pad will be happy!

Danno

The GFS PARA model is playing this out quite similar to the December 2017 event, however seems to be more snow getting into the east and southwest with this.

sryanbruen

U.K. Met Office have named this as Storm Christoph.

Danno

Danno wrote: »

The GFS PARA model is playing this out quite similar to the December 2017 event, however seems to be more snow getting into the east and southwest with this.

Naas had rain in that
Tullow Co carlow had rain but carlow town had several cases of snow just a few kms further inland
As the then snow band slid southeast, snow fell at sea level on the coast in waterford, the cold air travelling with and staying in position inside the front
The part which had already turned to snow sliding into waterford whereas further up the east coast the marine and rain influence remained
Here in Arklow and near the Irish sea the snow line was 400 metres and stayed that way in marine influence that pushed in to cover much of kildare

Kermit.de.frog

For snow potential there is uncertainty as to how far north rain bands get through Wednesday. Quite a mix of outcomes. I'll wait until later to see if it's more conclusive. The further north the greater the chance of snow.

In relation to flooding I see ME going for up to 50mm in some places. I'd go along with that. Could be a little more locally. Rain kicks off this evening in all areas but focus is north Midlands, North Leinster, South Ulster and North Connaught for flood potential.

Just to add,the difference between this event is in the South east this time wind is off the land not the sea
Huge difference especially to the east of high ground if snow is going to fall to sea level
The cold air digging will also have had a long land track over the island to South leinster especially neutralising a lot of its marine wateryness
More guidance tomorrow and probably even Wednesday needed to call this

nacho libre

It looks more wet than white for alot of us, unless there is a big change. Hopefully it does not start trending more south to the point that everyone misses out.

John.Icy

My part of S.Kildare (near the Carlow/Laois border) had a great time of Dec 2017, lots of snow. You could throw a sheet over the regions of S.Kildare, East Laois and parts of N.Carlow that did really well out of the event in terms of majority snow (away from high ground), rather than waiting for a transition or back edge action only.

There was also a frontal event on the 13 Nov 2019 that this same zone saw heavy snow while many others just saw rain. Maybe a few other regions too but we seem to have a fair few posters in this area and I don't remember seeing many places with as much snow as Athy, Port Laoise, Monasterevin etc. and other towns within the similar region.

EDIT: If onshore winds aren't that much of a factor the above may all be irrelevant.

ninebeanrows

It is all relying on evaporative cooling to enhance the cold undercut.

Just checking this morning's runs and the risk is reduced as the occlusion is set to slide somewhat further east than some runs yesterday.

If low develops a bit quicker it will increase the chance of the occlusion trailing over the east and southeast for sometime..

It is very much a marginal event that requires reasonably intense precipitation, profile aloft should be sufficient for snow if lower layer can be cooled by the precip intensity, but this morning's output seem to lessen the risk of intense precip and clear the system quicker

Arpege usually give a good idea of where wintry precip is most likely.

Places like Carlow and Wicklow seem favoured at the minute

Gaoth Laidir

Current snow lines (m amsl), from the 12Z radiosondes. Not great up north. On Wednesday we'd be relying on some fairly substantial uplift or surface cooling to turn things to snow down the midlands. Evaporative cooling should not be possible as the lowest layers will be already saturated.

MJohnston

It's going to be a wet couple of days, but the ECM 6Z isn't having any snow other than in high lying areas:

Kermit.de.frog

Oh I dunno. Seems to be a dose of healthy scepticism that may yet turn out to be unhealthy in the end. If we look at the GFS (upcoming) this is exactly what we want to see. The snow level falling all the time. This is just one of a variety of outcomes but it's an example of what could well occur.









The 6z ECM is actually a bit of an upgrade in terms of potential - just need a little bit more evolution from there. A tad more northwest and boom!

I wouldn't be calling things either way. I think we have a good chance here but it depends ultimately on the location and orientation of those frontal zones. Long story short the further north the better and that's what i'll be looking for.

Gonzo

hopefully this proves further north and further west but at the moment i'm not expecting much if anything here in Meath unless there is an upgrade with the positioning. This could easily miss the entire country as well.

nacho libre

Gonzo wrote: »

hopefully this proves further north and further west but at the moment i'm not expecting much if anything here in Meath unless there is an upgrade with the positioning. This could easily miss the entire country as well.

All I'll get is accumulations of rain. It's fantastic if you love rain , i suppose. Anyway good to see a forum tradition is being maintained this thread

Gonzo

nacho libre wrote: »

All I'll get is accumulations of rain. It's fantastic if you love rain , i suppose. Anyway good to see a forum tradition is being maintained this thread

no shortage of rain over the next 10 days either. A very wet 3 days to come, then dryer and next week is already starting to look like plenty of regular rain. January will definitely exceed 100mm in places by the end of the month.

Kunta Kinte

Gonzo wrote: »

no shortage of rain over the next 10 days either. A very wet 3 days to come, then dryer and next week is already starting to look like plenty of regular rain. January will definitely exceed 100mm in places by the end of the month.

And what about February? More of the same then?

Gaoth Laidir

Kermit.de.frog wrote: »

Oh I dunno. Seems to be a dose of healthy scepticism that may yet turn out to be unhealthy in the end. If we look at the GFS (upcoming) this is exactly what we want to see. The snow level falling all the time. This is just one of a variety of outcomes but it's an example of what could well occur.

The 6z ECM is actually a bit of an upgrade in terms of potential - just need a little bit more evolution from there. A tad more northwest and boom!

I wouldn't be calling things either way. I think we have a good chance here but it depends ultimately on the location and orientation of those frontal zones. Long story short the further north the better and that's what i'll be looking for.

Nothing showing in those charts imo. Still a sloppy mix at best. I'm not seeing any difference in the 06Z ECM, and all other higher-res models in agreement. The showery troughs following on later on Thursday may have some more wintry intensity-based snow but the overall airmass is just a regurgitating Atlantic slop-fest, unless something drastic changes.

ninebeanrows

Local HIRES model ensembles say yes to snowcover in many parts of Leinster by Wednesday evening.

Long way to go though and will be sloppy for most

Supercell

The T+60 fax has the occlusion well south of us by midday, with a slack cool airflow, I really dont see anything but rain bar the usual high places in Wicklow mainly.

Supercell

Supercell wrote: »

The T+60 fax has the occlusion well south of us by midday, with a slack cool airflow, I really dont see anything but rain bar the usual high places in Wicklow mainly.

Those fax charts seem to change every issue
The 528 dam on the last one they did covered all of Ireland bar cork and kerry
There it avoids the whole country
Rain glorious rain
There'll be another different one tomorrow

OldRio

More rain. Sigh. Flooding. Sigh. Feck you January. Horrid month.

Gonzo

Kunta Kinte wrote: »

And what about February? More of the same then?

We could have a mild and wet start to February. The Atlantic looks well and truly back in business over the next couple of weeks. We lose the blocking for a while and there are signals it may come back during February but that's really too far out to know how February will shape up. By then I think most of us will be looking for an extended relatively dry period.

pauldry

Yeah more rain. We had 60mm in Sligo last week. Now looks like another 60mm by Thursday.

....and we are only 56 days into neverending January

mcburns07

Gonzo wrote: »

We could have a mild and wet start to February. The Atlantic looks well and truly back in business over the next couple of weeks. We lose the blocking for a while and there are signals it may come back during February but that's really too far out to know how February will shape up. By then I think most of us will be looking for an extended relatively dry period.

What the models are showing for the start of Feb is surely irrelevant right now considering how accurate they are? I'm all for realism but a bit of optimism would be welcome too

Billcarson

I'm hoping that during next week the models will start improving regards cold for early feb.

Sleety_Rain

Sleety_Rain wrote: »

Local HIRES model ensembles say yes to snowcover in many parts of Leinster by Wednesday evening.

Long way to go though and will be sloppy for most

Just seen it (if it's the 12z Harmonie)
Basically at 6pm snow in West and south Dublin ,all of wicklow,most of laois,carlow Kilkenny, all of wexford and much of inland waterford
Basically a whole swathe of the southeast
Looks like higher parts of Dublin but if the map I'm looking at for that time were to verify,you'd have it in places like Ballinteer Tallaght and maybe Dundrum but not Donnybrook

Just south of Dublin to south wexford,it brings the snow right to the coast at that time

Kermit.de.frog

The southeast looks good for some snowfall but this could end up further north or south. Still changes to come.

ICON and GFS keeping snow more or less to the southeast counties for now. All depends on whether this nudges further north or not.

Also the wind is off shore quicker further southeast which is why some models have snow falling to the coast. In Dublin we need to lose the on shore component.

nacho libre

Billcarson wrote: »

I'm hoping that during next week the models will start improving regards cold for early feb.

Uk Met Office:

Sunday 31 Jan - Sunday 14 Feb
Confidence for this period is low, though there is a signal for weaker than average westerly winds and for Atlantic low-pressure systems to track further south than normal. This will bring below-average temperatures to the north of the UK, with a greater than normal risk of wintry precipitation. Further south, there is a continued risk of unsettled conditions, with above-average rainfall and periods of slightly above average temperatures. There remains the potential for significant snowfall along the boundary between colder air to the north, and the milder air in the south, with the greatest risk across central and northern areas. Through this period there is a greater than average chance of cold spells spreading across the whole UK at times with the associated risk of wintry hazards.

The last line holds out the hope you just might get your wish

pad199207

Kermit.de.frog wrote: »

The southeast looks good for some snowfall but this could end up further north or south. Still changes to come.

ICON and GFS keeping snow more or less to the southeast counties for now. All depends on whether this nudges further north or not.

Also the wind is off shore quicker further southeast which is why some models have snow falling to the coast. In Dublin we need to lose the on shore component.

Is there anything to be said for saying another mass?

Davaeo09

pad199207 wrote: »

Is there anything to be said for saying another mass?

Or ten

Its on such a knife edge too

pad199207

Davaeo09 wrote: »

Or ten

Its on such a knife edge too

Completely. Marginality at its finest if ya ask me despite all the beautiful dazzling snow accumulation charts :rolleyes:

Davaeo09

Let the truth be told most of us enjoy this roller coaster regardless of the outcome

This time its so marginal yes, but the reward could well be worth it.
There's plenty of potential now for the South East/Mid lands again and the North look likes it will get its share before thee weekend is out.

Lets hope its not a sloppy snizzle fest and a good few of us get rewarded for our patience.


Once again a big thank you to everyone here that contributes. I feel I've learned allot over the years reading posts from some of the very knowledgeable people amongst us. We are blessed.

Donegal Ken

The Met Eireann HARMONIE model is currently showing rain turning to sleet or wet snow in parts of the east and southeast later Wednesday afternoon and evening. Most accumulations will really be over the higher ground areas there but at this stage slushy deposits cant be ruled out across some lower level areas. Some accumulations across higher parts of Ulster will occur from Tuesday evening and night noting for lower level areas. Big risk of very icy roads across the Ulster and northern Connacht Tuesday night and before dawn Wednesday morning with some area see lows of 0C to -2C with the heavy rainfall just cleared roads and footpaths will be very wet with ice forming quickly.

Gaoth Laidir

Donegal Ken wrote: »

The Met Eireann HARMONIE model is currently showing rain turning to sleet or wet snow in parts of the east and southeast later Wednesday afternoon and evening. Most accumulations will really be over the higher ground areas there but at this stage slushy deposits cant be ruled out across some lower level areas. Some accumulations across higher parts of Ulster will occur from Tuesday evening and night noting for lower level areas. Big risk of very icy roads across the Ulster and northern Connacht Tuesday night and before dawn Wednesday morning with some area see lows of 0C to -2C with the heavy rainfall just cleared roads and footpaths will be very wet with ice forming quickly.

Slushy deposits. That's something to look forward to!

esposito

It's better than 100% rain and it will be nice to see flakes falling even if it is of the wet variety. Tough times ya know so I will take it.

Davaeo09

and considering there was no mention this time yesterday, one can pray and do a snow dance :pac:

Captain Snow

pad199207 wrote: »

Is there anything to be said for saying another mass?

pad199207

Captain Snow wrote: »

Tzardine

I am just outside Kildare village. I am getting excited.

This is my current mood.

Kermit.de.frog

Ok he has had his mass...back OT...rain gathering from the west - just to remember there is a risk of flooding over the next 36 hours across north Leinster, Connaught and south Ulster in particular.