Friday Jan 2nd onward, very cold with snow potential: Event buildup/discussion

pauldry

These charts are the best for many years even if they come to nought. 2018 or 2010? Northeaster is a good direction. Might turn Northwest though and hail rain and snow but frozen rain. But definitely some places will see snow. Mountains 100% some inland areas 70% or more.

Lucreto

I have a snow shovel in my amazon basket. I probably just jinxed it.

Perfidious Cretin

Moved into a new house a few months ago that's 220m asl. Might have to invest in some snow chains, just in case...

Calibos

https://www.boards.ie/discussion/comment/124101090#Comment_124101090

If your tyres aren't in need of replacement any time soon, some chains or Snow Tyre Socks depending on the price might be a worthwhile purchase. However if the tyres are nearing time for replacement anyway, I'd say its well worth investing in a set of Michelin Cross Climate 3 tyres or well reviewed equivalent latest Gen All Seasons by other manufacturers. The likes of the CC3's are much better than old All Seasons from decades past which where mediocre in All Seasons. The CC3's and their 1&2 predecessors with the 3 Peaks and M&S symbols get great reviews and score better than all but the best actual dedicated Winter Snow tyres thanks to their Thread patterns and special Rubber Compound that stays soft in the cold for grip but doesn't melt and wear out rapidly in the heat of the Summer. They perform almost as good as a Summer tyre in Summer and in the Wet and the compound and thread pattern don't massively affect mileage, handling and aren't loud. Basically they dont suffer any of the old compromises.

Needless to say we don't get enough snow often enough for long enough even at 220m ASL in this country to warrant purchasing dedicated Winter Tyres and swapping Winter to Summer and Summer to Winter twice a year. The likes of the CC 1/2/3's are so well regarded they count as a dedicated Winter Tyre by Scandi and Alpine authorities in Europe with Winter Tyre Mandates but owners don't need to take them off in Spring like true Winter Tyre owners. They are thus perfect for us on these islands. You'll never get caught out by Ninja Snow. Except in extreme circumstances, won't need to faff about for 20 minutes trying to get snow chains on and given normal rubber compounds harden and start to lose grippiness at 7c and below, well even if you hardly ever see snow up there at 220m asl, you'll definitely see a lot of Sub 7c temps and the CC3's or whatever will provide better traction and breaking distances even if they never see a flake of snow.

pauldry

Looking at GFS now. Already watered down. Ends 6th January now. Modern climate no cold spells last.

Captain Snow

Not long now..

Condor24

Looks like a two to three day chillier spell this morning. Snow for northern parts, frosts for the rest. Maybe a reload later mid month. Not very exciting I'm afraid. We'll see later runs.

red_diesel

https://www.boards.ie/discussion/comment/124101114#Comment_124101114

6 years ago I got 2 Micheilin Cross Climate tyres on the front of my car. Shortly after getting them the car went out control on a bend, hit the ditch and was wrote off. No speed involved. Just lost grip. It was in April and I think 4 degrees and wet at the time.

King of Spades

https://www.boards.ie/discussion/comment/124101186#Comment_124101186

Snow is coming by the weekend, that’s not in doubt. It may just be favoured Northern locations or it may be countrywide. But after a completely snowless winter thus far and arctic sourced northerlies becoming like hen’s teeth, I think there’s every reason to be excited.

torres9kop

downgrade?

Thorny Queen

My local forecast is still giving 3 days of snow- Friday- Sunday.

endainoz

https://www.boards.ie/discussion/comment/124101271#Comment_124101271

Not to be taken at face value anyway. Won't know for sure until probably the day before.

Thorny Queen

https://www.boards.ie/discussion/comment/124101279#Comment_124101279

Ah jaysus...here we go again.

Rebelbrowser

https://www.boards.ie/discussion/comment/124101265#Comment_124101265

Things are fluctuating as you would expect in an unusual set up still several days away but, no, to my untrained eyes no downgrade for the first 3 days of the spell, cross model support. Worry about the rest of it later….

stephenjmcd

https://www.boards.ie/discussion/comment/124101297#Comment_124101297

Snow in Ireland is extremely difficult to forecast more than a day away.

pureza

https://www.boards.ie/discussion/comment/124101265#Comment_124101265

There is no such thing as an upgrade or downgrade

There is an ensemble with many members (runs within a run if you like) within it

Forecasters often look at the mean of those member to see where the higher likelihood or direction of travel is and that’s definitely for a non climactic norm feed of winds for a while

As I stated in the FI thread though,the source needs to be a lot,an awful lot colder if it’s coming in from the north or northwest to affect the higher populated low ground coastal areas

Less so with an easterly

The physics of that is quite simple

1000’s of km’s of modifying warm Atlantic surface sea air to cross vs only 60 to 100 km’s of Irish Sea having in the case of easterlies exited a very cold GB and Europe and not too much sea

You need about 60kms of water for super cold 850mb temps (air at about 1500 to 1800 meters) overhead to cross for showers to develop

That’s what for example in Feb 2018,a week before Emma you had so much snow barrelling into parts of Dublin and Kildare from showers

The east wind from Liverpool bay in the crossing had enough water to suck up to build those showers

That’s called fetch btw funnily enough

There is obviously plenty of fetch in the Atlantic but too much warmer water surface air in the mix

Rare easterlies,true long distance easterlies don’t have that problem

To mitigate it in northwesterlies or northerlies the flow has to be very strong or ideally sourced from the northeast to be curved around into a north or northwesterly

Combine that with -10 860mb temps and you’ll have a snow fest of great magnitude in the populated coastal west and north

It’s then called ‘returning’ polar continental air

So don’t get fixated on particular operational runs my friends,listen to the frogs comments on what kind of air is coming and where

Rebelbrowser

There are very few parts of the country not at least capable of getting snow if the flow is fluctuating from NE to NW. Pure northern flow would largely mean ulster only but thats not what is currently being forecast. I remember even my location on the south coast getting 4 or 5 inches off a NW flow on 17 December 2010 as that spell started.

stephenjmcd

https://www.boards.ie/discussion/comment/124101218#Comment_124101218

I wouldn't say thats not in doubt. Its not nailed on that anywhere gets snow. Some places would have a chance alright but models change daily so its wait and see territory still

Billcarson

https://www.boards.ie/discussion/comment/124101265#Comment_124101265

The Gfs isn't great for longevity and ends things early next week but the Ecm which is a better model....

Cluedo Monopoly

If someone offered you a bone dry Christmas holiday period with a possible snow event to end it, you would have bitten their hand off. The odds are always stacked against us but it's still possible.

Calibos

https://www.boards.ie/discussion/comment/124101193#Comment_124101193

Its never recommended to run different tyres with different grip levels, tread patterns and tread depth front and back and when one decides to disregard that, its recommended to put the newer better gripping tyre on the back regardless of whether its a FWD, RWD or AWD vehicle. The reason being that its easier for most drivers to react to and maintain control in an Understeer situation where the front loses grip first than in an oversteer situation where the less grippy back slips out. You put the pair of Cross Climates on the front. I wouldn't be counting your anecdote as an argument against Cross Climate All Seasons or similar tyres from other manufacturers.

Taking those recommendations into account, unless I owned a RWD or rear biased AWD car where you get the traction benefit in the snow and ice as well as oversteer mitigation, I’d always just wait till I could afford a full set of 4 Cross Climates for a FWD car because with a pair only on the back, they wont help one get moving or climb inclines at all in the Snow and Ice so why bother. ie. Don't have to worry about oversteer on the snow and Ice if I cant get moving in the first place.

Meteorite58

https://www.boards.ie/discussion/comment/124101335#Comment_124101335

Mod Note: Duly noted Aimsir2025.

nacho libre

Wow the latest ECM is very snowy at times. I suspect our old friend polar low may pay us a long overdue visit. The great thing about a polar low is it often gets areas in the on the action that might other wise miss out. How great is it to have a cold spell in the heart of winter coming into the reliable. I remember the week before the reload in December in 2010 I was giddy with anticipation, barring a major downgrade this week will be similar I feel. If this does come to pass i am going to have another drink or two to celebrate- it would be rude not to!

Captain Snow

Get in.

nacho libre

https://www.boards.ie/discussion/comment/124101379#Comment_124101379

What a sight!- its a rare thing to see the 510 dam line approaching Scotland . Oh happy days! Just look how far south the 528 line gets too!

JanuarySnowstor

This cold spell is a potent 2 day toppler at the moment. We won't do any better with a big fat high moving into Western Spain

highdef

"I am detecting downgrade vibes..... right across a number of forums and individual forecasting accounts on X....."

@Aimsir2025, can you go into further detail on this regards to the forums in question? Perhaps some quotes or excerpts would be helpful to others here. Can you elaborate on "individual forecasting accounts on X" - Are they from individuals like you or I, or from actual Met agencies? I'm not seeing these so called vibes where I am looking but I'm open to discovering new supporting evidence that you are clearly privy to. Many thanks in advance.

JanuarySnowstor

https://www.boards.ie/discussion/comment/124101394#Comment_124101394

It's a common occurrence to see the 510dam line come near us in cold spells. It happens quite regularly, more so in Polar Northwesterly's. Indeed it's quite a bit away from us as in Northern Scotland. Also the 528 line is hovering near the West Coast throughout which isn't ideal

endainoz

https://www.boards.ie/discussion/comment/124101402#Comment_124101402

No point in wasting your time there

Captain Snow

Heading for a reload. Like the ECM.