FI Charts ( T120+ onwards) Winter 2023/2024 **READ MOD NOTE IN FIRST

WolfeEire

Here is the GEFS set. Screenshot it for posterity. The tables feature all 30 members of the GEFS from top to bottom:

850s

2 metre air temps (red line is average of all)

850s

P

bazlers

https://www.boards.ie/discussion/comment/121601799#Comment_121601799

https://www.boards.ie/discussion/comment/121604711#Comment_121604711

Dont forget the Magpies and Squirrel 😉

Hopfully the trend continues.

WolfeEire

The 18z ECM is 0.5c to 1 cooler than the 12z in the period up to the end of Wednesday (end of this run).

Daytime temperatures (2 metre readings below) on Mon, Tue and Wed will be 2-4c at best and will stay closer to freezing in inland Ulster and parts of the north Midlands.

The 850s stay under minus 5c from Sunday evening through to Wednesday night, unlike the 12z which crept up to minus 4 territory due to that persistent warm sector on Tuesday, which is less forceful here due to heights not extending as far east.

Precipitation levels for the period are low, but do not account for unforeseen troughs that may form in the northerly airflow, and more likely in the subsequent slack northeasterly. It's quite an unstable airmass by then (Tuesday into Wednesday). Tuesday in fact presents moderate potential for a slow moving band of (mostly) light snow to move down across Ulster, which may start to dissipate as it reaches the middle third of the country.

The wider scatter later Monday reflects members interpreting to what extent that mild sector will deliver a brief rise in 850s and not necessarily surface temps.

Overall, a slight move to colder to conditions when compared with the 12z EMCWF Ens.

pauldry

Next Thursday would seem to be D day if you ask me. That's the best day for snow potential. All the days before this are hope. And after the Atlantic probably ruins some of it for a few.

WolfeEire

Decent output overnight.

ECM op run brings the Azores low a little further north to skirt southern England by midweek. Turning very cold Sunday night and lasting through the week with daytime temps likely to stay below freezing in some spots. A return to less cold and unsettled conditions likely on Saturday as all blocking quickly breaks down. Potential for precip from Atlantic systems to fall as snow for a while on higher ground at the weekend.

Very cold UKMO up to the end of its run (Friday).

ICON also very cold up to the end of its run on Friday.

132hrs of JMA completed. It has produced its coldest run to date with minus 8 850s covering the entire island on Monday

Coldest GEM output to date for the upcoming cold spell. The colder airmass starts to get diluted during Friday on the op run but the GEM Mean stays cold well into Saturday. Potentiality quite a snowy run.

GFS is cold until early Saturday with one milder sector that is overegged by the op run (outlier). The op run is also quite different in its evolution to the 18z beyond Thursday. The GEFS Mean not quite as cold as the 18z (850s about 1c milder). The mean stays below minus 5c from Sunday eve. The warm up later Friday into Saturday is much more extreme on the op run than the Mean. By Sat evening, the 850s are 3c on the op and minus 3c on the Mean.

GEFS 850s below

A return to less cold and more unsettled conditions highly likely from next weekend as things stand.

JanuarySnowstor

Amazing charts this morning, big upgrades on what we were seeing 2 days ago. Ice days and snow chances daily with nighttime minimas surely heading for minus 7/8!! Expect Met Eireann to up the ante soon with early warnings etc. This is school closure type cold even without the snow

Cork2021

https://www.boards.ie/discussion/comment/121604895#Comment_121604895

RAMP!!!!!!

Rebelbrowser

All the models still pretty different at short ranges. All agree it will be cold from Sunday afternoon to Thursday but even that cold is modelled pretty differently by them all. UKMO the coldest for sure, winds straight from the pole all week...

SpitfireIV

https://www.boards.ie/discussion/comment/121604895#Comment_121604895

I wonder where MT gets his data because given the upgrades or improvements in the charts I found his forecast rather underwhelming, or am I wrong?

lawred2

Last night's ME forecast had lowest daytime temps next week of about 4 degrees. Most days were 6/7

They didn't seem to be in the same place as you all are at all

JanuarySnowstor

https://www.boards.ie/discussion/comment/121604920#Comment_121604920

He used to be very positive for cold years ago, all change now seems overly negative about even decent setups. Only he can tell us why I guess..my assumption is years of let downs re irish weather

almostthere12

Doesn’t MT mainly base his forecasts off the GFS? If so that would make a difference as it isn’t as bullish about the cold as the other models.

I’m south of Cork city and yo is giving me a max of 3C next week, change comes Thursday but not before there is a snow to rain event, that is based off last night’s ecm. It will be interesting to see how that changes with this morning’s ecm.

pureza

Has MT a typo there with northeast winds next week? Surely he meant Northwest?

Rebelbrowser

https://www.boards.ie/discussion/comment/121604923#Comment_121604923

You'd need guys like Pureza, Kermit and Sryan (and Gaoth Laidir if he is still around) to give you proper guesses on temps next week. There still seems an awful lot of uncertainty. I could see daytime temps being 5c or below zero still depending on which model is right. A huge issue will be if it snows. Then you get the lying snow cooling things. There will also be a big windchill not captured by daytime temp statistics. I'd imagine it's gonna feel below zero even if it isn't, especially if the UKMO is correct

Pangea

Back in the day when you would see MT writing Advance Alert you knew you were in business. Those were the days..

Reversal

Looking at direct model output for my area in Dublin and nothing giving day time highs above 2°C after Sunday.

MT forecasting much higher temps by day, perhaps his experience tells him something that the raw model output won't.

nacho libre

https://www.boards.ie/discussion/comment/121604925#Comment_121604925

He was challenged on a snow forecast years ago, the poster who did it turned out to be right. I noticed he became more conservative in his forecasts since. Anyway a cold week with temperatures struggling to get above zero at times. I really hope the GFS is being overly progressive as usual after that as we could be back to very wet weather for several days otherwise, but it's not a good sign with the pv back from its holidays. Hopefully we can get a surface high at the end of the week to prolong any snow cover.

JanuarySnowstor

https://www.boards.ie/discussion/comment/121604979#Comment_121604979

I'll be sticking with my own experience and the apps/meto look spot on. 2 to 4 looks about right, sometimes lower

bazlers

https://www.boards.ie/discussion/comment/121604979#Comment_121604979

I assume MTC sees alot of cloud cover at night which will act like a blanket. This will reduce tempertures getting down to the deep minus figures that we would definitily see in such a set up as shown (if clear skies and slack winds) thus would have an impact on max day time temps.

Just my take on his forecast.

icesnowfrost

Looking like a very cold week Monday to Saturday at least. Monday/Tuesday might see some snow but Wednesday/Thursday is the one we are all looking at.

I think the cold snap might last to the end of the month but how cold that is the question.

a very exciting next few days model watching.

highdef

https://www.boards.ie/discussion/comment/121604895#Comment_121604895

Wooooaaaahhhhhh, hold your horses. There's still a huge range of scatter amongst the various models and as it stands there's nothing majorly wintery showing up. Currently it looks like the most likely scenario is a cold snap lasting a few days in a manner which is to be expected in January. I see nothing out of the ordinary on the way bar standard January cooler than average conditions for less than a week with some snow in places but nothing out of the ordinary for January.

Yes, it will get colder. Yes, there will be wintry showers. Yes, some will see lying snow but I think most will not see lying snow. Northern and Western parts look like the most at risk from wintry showers, perhaps not sticking close to the coast but more likely than not further inland and on high ground. There is of course the chance of some disturbances popping up next week that are not currently modelled as they occur beyond the reach of high resolution forecasts.

It looks likely that we will be back to an unsettled and often mild Atlantic driven pattern by the end of the week by I truly hope I'm wrong on that as some of the computer models throw up some horrific scenarios, if you're not fond of wind and/or rain, like myself!

Your comment about school closures with no snow is a bit on the sensationalist side and does not add anything useful to this thread. I can't see why a school would close if it's dry and a bit on the cold side however for the moment, it would be best to stick to the forecasted weather outcomes rather than personal opinions on what decisions the Department of Education or individual school principals may make during next week as that kind of thing is currently superfluous in this thread, based on the model guidance at hand up to now.

I would urge caution when posting. Stick to the facts. Compare the various models. Don't let your desires get involved. Northerly based cold snaps rarely deliver for most......of course those in many northern and western parts will very much disagree but when I say most parts, I mean that any severe impacts generally occur in a smaller fraction of the country where an even smaller fraction of the population reside.

There was that recent non-event in the south of the country where you were extremely confident that there would be a good snow event in many southern parts. Many disagreed (including myself), including "seasoned veterans". There was very little to support a decent snow event in the south but you were confident it would occur and I think (and I am open to correction) that you had a personal bias for it to occur so that your wants and desires took over your thoughts to some extent, even when the main computer models showed, at best, trace to small coverings of snow inland of the south coast.......which is more or less exactly how it transpired.

From my POV, I'm still not convinced that there will be anything noteworthy next week apart from weather to be expected in January but I will be keeping a close eye on the models as I usually do. We'll be moving into high resolution modelling in the coming days and by then we should begin to see the bigger picture, get a better understanding and be in a place where thoughts on details and specifics should become more likely to transpire as things are still very fluid as it stands.

For what it's worth, I would love a good snow event with ice days; I just keep my heart out of it and use my head.

PukkaStukka

https://www.boards.ie/discussion/comment/121605443#Comment_121605443

Same measured approach here. It'll be cold but little risk of anything more wintry, and likely not to last more that five days.

squonk

Agreed. Yeah it’ll be cold. Not 2010 cold. I don’t see any indication for my location from the likes of YR that it won’t be acting more than a decently fruity outbreak with low daytime temps. Nothing epic I can see me remembering for years like 2019, 2009/10. Really after that huge chase and model upgrades I remain kind of nonplussed that a fairly fruity shell is all it’ll actually mean. I’ll wait and see though.

Derekon2021

https://www.boards.ie/discussion/comment/121605443#Comment_121605443

What a brilliant, balanced and sensible post. Next week looks chily & dry. There's no accounting for the nonsense over on Netweather UK, which appears to be slowly taking hold here!

Like 2009, 2010 and 2018, actual snowfall (and not people's hopecast/imagination) will be well flagged by the likes of MT.

D

kingshankly

Folks stop doing this to yourselves 😂 how many times !!!😂

Hairypoppins

https://www.boards.ie/discussion/comment/121604998#Comment_121604998

Are you looking for school closures with these sort of daytime temperatures?

nacho libre

It's out of the ordinary in a sense for what we have become accustomed to in January . It's true there won't be a huge amount of snow around anywhere, but if 2018 and 2010 are the bar these days then you are inevitably going to be disappointed. I am looking forward to possible ice days at some stage next week, that to me is noteworthy enough given that cold spells in January are not that common in recent years. A bit of snow will be a nice bonus

Condor24

GFS bringing back the Atlantic, roaring in from next weekend. We have a three day cold spell looming in the meantime and that's it. Anyone looking for lengthy cold is going to be disappointed. We may get something again in February, another 3-5 day wonder and that'll be that. Don't shoot the messenger!