FI Charts ( T120+ onwards) Winter 2022/2023 **READ MOD NOTE IN FIRST POST**

Can we please keep the tread to the technical discussion rather than who said what and who. Really interesting few hours ahead. No point worrying about where gets snowfall and when at this stage it's gonna be at least Tuesday before we have any real idea. Latest indications suggest northern counties are mostly likely to see some wintry precipitation moving into Wednesday night and Thursday and possibly more organised showers moving down across Ireland on Thursday but it's going to Tuesday at the earliest before we have any real idea. The good thing at this stage for cold weather lovers is that there is a cold spell coming compared to what we have been experiencing recently. That low pressure system is most likely move of to the south of Ireland later next week into mainland Europe.

Yes that's the most likely outcome. Tomorrow will give us a fair idea. That low pressure system into the following week at this stage nearly a waste of time looking at it as we are going to see some many up and downs. The end of next week is the period that needs to be watched this stage.

Whatever about snow potential later in the week, it's really really great to have the Atlantic turned off for a week after those crazy 3 months and have a settled spell. The east wind is a bit miserable on the East coast but it's a real treat on the West coast.

The charts this morning look like they have real trouble dealing with the weekend and beyond, a range of options on the cards. GEM the best of them for prolonging the cold, the others don't seem to know what to do with that crazy Azores low, it's a very unusual setup so presumably they don't have a massive amount of historical data to work off for these scenarios.

Yes the trouble is that Northwesterly wind that's going to set in up here...even with the whole system coming from the Northeast. This is going to cause mild sectors coz the wind will be coming in off the Atlantic so even though the Northwest sees the bulk of the showers the coastal areas will just get 4 or 5c and rain hail and sleet whereas a few miles inland away from the coast will get sleet and snow and temperatures only about 1 or 2c . So just like a lot of cold spells it depends where you are but inland does best and the East and Northeast may also do well. The South and Northwest coast less so due to the dreaded Northwesterly. Media will call it a beast from the East and yet still a Northwest wind. Ya can't win.

And what about the weakening heights to our North? Gone from all 3 models by day 7 ?

It isn't all about that low, we have agreement that Northern heights are not going to sustain at 7 days out not deep FI

Well the problem is some people can't manage their expectations, so inevitably a two to three days cold spell will not be enough for them. Also they will downplay prospects of snow if there is little for their area. I think the first low will slide away, but the second one being futher north may lead to milder air winning out. If we are lucky we could get an epic snowfall before that happens. As it is, like you say, some places should see a bit of snow between Wednesday and Saturday.

Winter Weather Advisory for Ireland

Very cold this week as an Arctic airmass sets in, bringing sharp to severe frosts and icy stretches on roads. Showers of hail, sleet, and snow will occur during the second half of the week. Updates with potential warnings will be issued in the coming days

For winter weather preperation: www.winterready.ie

Get your 10-day location forecast on: www.met.ie

Valid: 11:46 Sunday 04/12/2022 to 23:30 Saturday 10/12/2022

Issued: 11:46 Sunday 04/12/2022

And just to add the background signals/teleconnections are still favourable towards blocking. While that is the case there is always the possibility of further cold outbreaks even if we do get milder weather after next weekend.

As things stand re: long range (FI), the ECM and GFS indicate a breakdown of the cold from the end of next week due to a collapsing of the Greenland blocking high and a rapidly intensifying area of low pressure quickly tracking northeast over or close to Ireland introducing warmer air

The GEM and JMA keep the cold in place into the following week. JMA has been consistent in this outlook, while the GEM has never really bought into a prolonged or particularly potent cold setup until now.

All models, including the UKMO, agree on cold weather with some wintry falls in places up to and including the beginning of next weekend even if there is a maritime influence in that airmass extending over Ireland. It's quite an unstable airflow which means criteria for snow that we are used to with upper air temps, surface temps, freezing levels, SST etc may not be as rigid.

A cold spell was looking less likely two days ago but models are now in full agreement on same. I would say a continuation of cold weather is very much up in the air, pun intended but changes in GFS and ECM output would need to reflect this over the next 36 hours. The ensembles for both are trending to a slow warming from next weekend.

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Aside from this, Met Éireann has issued an advisory

Winter Weather Advisory for Ireland

Very cold this week as an Arctic airmass sets in, bringing sharp to severe frosts and icy stretches on roads. Showers of hail, sleet, and snow will occur during the second half of the week. Updates with potential warnings will be issued in the coming days

For winter weather preperation: www.winterready.ie

Get your 10-day location forecast on: www.met.ie

Valid: 11:46 Sunday 04/12/2022 to 23:30 Saturday 10/12/2022

Issued: 11:46 Sunday 04/12/2022

Thursday might be good. I think Meteoriteite58 posted a -10 850 last night crossing the country.

Be nice to get this cold spell done then a reset for more blocking scenarios around greenland / scandi into siberia ready in time for Christmas.

Although that might be my Heart over my head talking.

Never thought id be hoping to get a cold spell out of the way for a better bite of the cherry! Getting greedy now but there seems to be a greater chance this year of something memorable than there has been in years from what im seeing and reading and yet we struggle with whats happening in 3 days time : )

We live in hope. If things do come good for Thursday make sure you get out and enjoy it.

12z GFS, out beyond Day 8. Shows what may happen * if * the Azores LP alongside the one GFS is keen on developing at the tip of Greenland play ball and undercut/slide to our south, heights rebuilding to our north. So much to happen between now and then. Anyone would be mad to think too far ahead! EDIT: Albeit all these dartboard lows rarely come off, so not sure if the below is worth a penny.

GFS essentially back to where we started with a prolonged cold spell and a reformation of the blocking pattern. Although I wouldn't put much faith in it at all. How it handles those lows is incredibly strange as SleetAndSnow says. The correlation performance to reality ratio of the new GFS remains pitiful.

GFS keeps the cold spell going through to the end of the run. The moyenne/average above for Saturday favours a continuation of cold conditions beyond this point with the Azores low not as explosive or making as much progression northeast as previous runs.