FI Charts ( T120+ onwards) Winter 2020 **READ MOD NOTE IN FIRST POST**

Gonzo

Mod Note

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The golden gates of winter have finally swung open with hopes and dreams of white gold. Last winter was truly abysmal with the Polar Vortex of Doom writing off winter 2019 before it even began. This winter can only be better than last winter.

The next 2 weeks looks mildly interesting for now. It looks fairly chilly over the next 10 to 14 days and after that we may see a return to milder conditions as we head into the second half of December.

The trend is for the NAO and AO to go negative over the next week which may allow northern blocking to be become more of an influence on our weather. This will turn the winds into the north or different variations of northerly winds from the north-west or possibly the north-east. An easterly could also develop in the next 2 weeks, something to watch out for.

The ECM looks fairly chilly over the next 10 days but nothing too cold.



The next 2 weeks also look dryer than much of November but some showers or bands of rain or sleet cannot be ruled out.

The GFS is fairly cool over the next 2 weeks and trends milder as we head towards the middle of the month.



Hopefully we will see a few flakes over the next 2 weeks but for now it appears very marginal with snow more likely over high ground. At least things currently are much more interesting than this time last year when we had a relentless raging Atlantic.

nacho libre

According to the latest GFS the monster Russian high is not going anywhere by mid- month. The Atlantic is well and truly blocked. So no sign of a return to raging zonality, but no pronounced cold spell indicated as of yet. Still we could get something interesting further down the line. It's drastically different to last years setup.

nacho libre

Well the ECM op is now showing the Atlantic returning to some extent. Usually it would be the GFS being more progressive in this scenario. It will be interesting to see if the ECM tonight sticks to it's guns, let's hope it move towards the UKMO -
as that looks like the best for extending the cold.
In the longer term, hopefully events in the troposphere have a significant effect on the strat. A nice Christmas present would be a SSW in late December, that way if the things fell in our favour we could get a decent cold spell by late January, perhaps a bit sooner. Although a SSW before January is not likely.

dacogawa

10 days out but worth keeping an eye on... GFS is only dropping to 975.

Meteorite58

Under the influence of LP's out to +240 hrs, looks unsettled , in general not as cold as this current spell it would seem.

Meteorite58

dacogawa wrote: »

10 days out but worth keeping an eye on... GFS is only dropping to 975.

Met Eireann 'Further outlook: while it looks to get milder, current indications are for more active period of wet and windy weather at times later in the week and over the weekend'.

Rebelbrowser

I knows its the CFS but it now shows cold weather from 18 to 25 December, with steamers up to and including Christmas day, followed by a repeat of March 2018 from Stephen's day onwards! See for example:-



Just the usual boring -14 uppers down here.....

circadian

Rebelbrowser wrote: »

I knows its the CFS but it now shows cold weather from 18 to 25 December, with steamers up to and including Christmas day, followed by a repeat of March 2018 from Stephen's day onwards! See for example:-



Just the usual boring -14 uppers down here.....

I know it's way too far out to be nailed on but It would be the 4th Centre Parcs trip we've missed this year if that's the case. However, missing it for an epic dumping of snow as opposed to the pandemic would keep the wee'uns happy.

Kermit.de.frog

So long as the jet stream remains to our south we always have a chance of dragging in colder air from the east. The problem right now is that there is no real cold pool there to tap due to a persistent Russian high pressure which is driving milder air up through western Russia and eastern Europe from the eastern Med.





Temperatures well above average



We need to see an ejection of cold air out of the Arctic in to this region (or at least Scandinavia) before our prospects improve.

However there are plenty of indications in the models that low pressure from the Atlantic will struggle to break through and rather continue to slide southeast in keeping with the more southerly tracking jet.



So we end up with these synoptic situations.



Almost perfect. All we are missing is the cold air to tap. That can change super fast though. All it takes is low pressure going south through Scandinavia and maintaining high pressure to our north with that southerly tracking jet and we are in.

I'm quite optimistic meself.

I, for one, am stocking up on bread and snow shovels.

Meteorite58

Cant see anything of note that stands out up to +240hrs from the last couple of runs, looks milder next Sun and Monday but probably wet also and a bit windy Sun or Mon and then back to cooler weather from the W, N/W for a couple of days anyway it would seem . Meridional jet so looks like a pattern of mild - cool - mild/avg for now.

Reversal

This would make for an interesting lead up to Christmas.

Danno

Whoa!

torres9kop

Danno wrote: »

Whoa!

Surely we need a red warning out now!! Would that chart deliver large amounts of snow on the east coast?

lostweekend3

torres9kop wrote: »

Surely we need a red warning out now!! Would that chart deliver large amounts of snow on the east coast?

In theory, yes. NE winds appear to be the best for snow on the east coast. Pity it’s so far out in FI.

nacho libre

So the GFS has come around to the CFS idea. Cue the GFs on its next run showing a milder solution and a meltdown ensuing over on Netweather.
I think we can be fairly certain the Atlantic is not going to send a conveyor belts of lows from east to west for this rest of month, but are we going to get lows stalling close to Ireland and filling eventually, or will the gates to the beast from the north east(possibly north) be flung open by the systems doing the honourable thing and facilitating heights building to the north east?

pauldry

There is certainly a better chance than recent years and if mild weather does come there seems to be a bit of blocking going on so it will probably be short lived. If the current patterns persist the cold will only get colder. Might be an icy Christmas if not a snowy one.

Gonzo

fingers crossed we get something much colder and with snow before December is over, would be great to see. The trend is for the Atlantic to be well and truly back for January and once that happens it could affect us for the rest of the winter, keeping everything crossed for the next few weeks. There is a slight possibility that the blocking could remain in place for January and if that happened we could be in for some very cold weather indeed but most likely the Atlantic will get it's way for the mid winter period.

Gonzo

This mornings GFS ensembles are starting to show some very cold outliers towards the end of the run as we head into Christmas with 4 to 5 runs getting as slow as -6 to -10 uppers.



However there are also a lot of average to mild runs so we will need to see more of the runs fall into the freezer category over the next week to have faith in a proper cold spell around Christmas time, if it does happen it could be short lived but would be great to see.

edit: just for fun I also looked at the ensemble GFS extended that go to January 7th and some of those get as low as -12 to -14C, so it's encouraging to see that the models are still playing around with the idea of some very cold weather into the 1st week of January. Last winter there wasn't a whiff of cold in any of the models so this winter is certainly looking a bit more encouraging.

nacho libre

Gonzo wrote: »

fingers crossed we get something much colder and with snow before December is over, would be great to see. The trend is for the Atlantic to be well and truly back for January and once that happens it could affect us for the rest of the winter, keeping everything crossed for the next few weeks. There is a slight possibility that the blocking could remain in place for January and if that happened we could be in for some very cold weather indeed but most likely the Atlantic will get it's way for the mid winter period.

There are encouraging signs in the strat, so while the Atlantic might comes back, it might not run the show for the rest of the winter. This would reflect M.T. Cranium's thoughts for how the winter will go.

mcburns07

That's as close as we'll get to a ramp from Gonzo!

Meteorite58

ECM out to +240 hrs showing us under the influence of Atlantic Lows, no great winds apart from a few windy spells but showing some very wet days especially towards the end of the run for later next week, bit far a way to know for certain but at the moment would look like heavy rain coming up from the SW on a few occasions with flooding potential on the 12Z charts. With the rain comes some milder weather at times, no deep cold showing up but will still be coolish some days. Will see if this trends over the next few runs.

Danno

Most models are still going for some sort of easterly or northerly in the days just before Christmas. Cold air never too far away.

Gonzo

a few more outliers are going into freezer territory for the end of this mornings GFS run as we head into Christmas giving slightly more weight towards a trend towards something very cold for last week of December.



Most of the runs are still on the average to mild side but more and more are trending cooler with a a few genuinely Baltic runs getting close to -10C uppers. The extended GFS shows this potential cold spell starting around December 21st and lasting till about January 2nd.

We are along way out from reliable here, but hopefully we see continued cold trends over the next 10 days with more GFS runs and other models falling into line with something potentially very cold and hopefully snowy.

It would be truly fantastic to get a proper winter blast during Christmas week and into early January, would make such a change from waiting till March for the cold to arrive. Not looking for a 2010 or 2018 event but something decent like February 2009 would be very welcome and not too much to ask for.

pauldry

Certainly tending a bit colder. There have been a few milder runs though so its like 50/50 Id say. But this is 2020 so anything can happen. Also the conveyor belt of Southwesterlies is being met with more resolute blocking than last year and while some mild spells are likely in the short term they dont seem to be never ending as on most runs they are getting pushed South.

As always a lot can change and even if the next run is a milder one on the GFS we would need to see a few in a row to dash our hopes and so far there seems to be a cold run a milder run a cold run...so lets see what the next one brings...

Humberto Salazar

Rebelbrowser wrote: »

I knows its the CFS but it now shows cold weather from 18 to 25 December, with steamers up to and including Christmas day, followed by a repeat of March 2018 from Stephen's day onwards! See for example:-



Just the usual boring -14 uppers down here.....

I really hate CFS. What purpose does it serve? Every run is different. You can't even spy a trend. CFS. Complete Faraway Sh1te.
That said, Ecm, who I respect much more, may be picking up that much colder potential from Christmas time, with East winds. Weak signals but still a possibility to be watched.

Gonzo

looking fairly chilly Christmas Eve on the latest GFS run.

nacho libre

I think it's safe to say we won't have Atlantic low pressure system barreling from west to east during Christmas week. The Russian high says no to that.
Hopefully the ECM shows something promising tonight.

PokeHerKing

nacho libre wrote: »

I think it's safe to say we won't have Atlantic low pressure system barreling from west to east during Christmas week. The Russian high says no to that.
Hopefully the ECM shows something promising tonight.

Nothing safe about predicting what weather we'll have in a fortnights time imo but I admire your optimisim!

nacho libre

PokeHerKing wrote: »

Nothing safe about predicting what weather we'll have in a fortnights time imo but I admire your optimisim!

There is no guarantee as you say, but looking at the northern hemisphere profile it looks unlikely that there will be a zonal onslaught in the next two weeks. We may get systems stalling close to or over us, but with the jetstream on holidays to the south we should not have a conveyor belt of low pressure coming our way

Cue the charts tomorrow showing the Russian High saying goodbye, and Atlantic systems lining up to cross over us!

pauldry

Yes it's all very uncertain. There is no distinctive pattern emerging yet as with some other years. This is why I think it will be just a dry calm Christmas.

I remember a Christmas eve like the above chart almost identical and it brought icy rain and hail to Sligo and Castlebar and the paths were very slippy that morning going to mass.

Danno

First Christmas Eve chart of 2020: Snow/sleet showers packing in behind a cold front with an occlusion over Ulster giving heavy snow well inland. Cold with evening temperatures ranging -1c to +3c (milder near coasts, especially W)

Danno

The first Christmas Day chart is out: Nothing for snow-lovers in the first offering, a cool NW airstream driven by low pressure to our north. This chart is for midnight on Christmas Eve into the big day - cool and breezy with patchy frost in sheltered areas of the Southeast leading to a sunny Christmas day for most with isolated showers, perhaps some of these wintry over the high ground of the N.

pauldry

Latest GFS run not a good one for snow. Atlantic very mobile in it. It just looks like a bog standard 7c Christmas Day on this run. Maybe snow in Scotland.

Hope next run pushes things South with calmer air over us.

Snowed last week when it was calm then at same temperature got windy and it all went to rain.

Gonzo

the past two runs haven't been great, appears to be less in the way of freezer outliers again and a movement back more towards an Atlantic setup unfortunately. Still time for this to change to something more positive but I was kinda hoping to see more in the way of ensembles jumping onboard with the cold at this stage.

Slashermcguirk

I think we will only really get a sense of what is shaping up for Christmas towards latter end of next week. I still think anything beyond 5 days to a week is just meaningless. Hopefully some cold will build over coming week. Continental Europe appears to be trending colder after a very mild run until end of November

Gonzo

Slashermcguirk wrote: »

I think we will only really get a sense of what is shaping up for Christmas towards latter end of next week. I still think anything beyond 5 days to a week is just meaningless. Hopefully some cold will build over coming week. Continental Europe appears to be trending colder after a very mild run until end of November

Hopefully we will have a much better idea by the 20th of December, we should know by then what is coming our way for the Christmas period, hopefully we will arrive at a much colder solution over the next 12 days to give us something to look forward to. Last thing I want on Christmas Day is a day like today or another very mild 13C Christmas Day.

leahyl

Gonzo wrote: »

Hopefully we will have a much better idea by the 20th of December, we should know by then what is coming our way for the Christmas period, hopefully we will arrive at a much colder solution over the next 12 days to give us something to look forward to. Last thing I want on Christmas Day is a day like today or another very mild 13C Christmas Day.

Oh the dreaded 13 degrees Anything below 6/7 degrees is acceptable for me at this stage! Something seasonal!

pauldry

Yes our past few Christmasses have been fairly boring

Last year on Christmas morning it was -1c and frosty in Sligo though

arctictree

Lots of disagreement in FI on the different GFS runs. Some really tasty looking cold charts but also some very mild ones too.

polarhullar

Every year this thread pulls at all our heartstrings I guess that's what make it so exciting when any snow does appear, like last week

Meteorite58

Just to add some fuel to the fire

pauldry

Latest GFS back with a cold calm Christmas. A lot of rain between now and then. Some mixed with sleet so if its calm there might be a few snowflakes though all wet.

Temperatures never get to the dizzy heights of 13c in the latest GFS bar maybe this week. Temperatures of 5 to 8c seem the order of the day most days and 2 to 4c at night.

Next GFS pub run will likely go all out blizzard or 16c Xmas day.

Gonzo

GFS looks reasonably mild and fairly wet up to about the 19th/20th of December so a fairly wet spell to come over the next 10 to 12 days. Christmas still looks up in the air with alot of runs from average to mild runs and a few genuine cold outliers, one of which is the GFS operational with a cold and dry Christmas. Still a long way to go with this one.

SeaBreezes

Whats icon predicting? It used to be good at spotting trends before the other models, ECM better on the final details tho.

Gonzo

SeaBreezes wrote: »

Whats icon predicting? It used to be good at spotting trends before the other models, ECM better on the final details tho.

The Icon extends out to December 17th and shows a mostly Atlantic scene with temperatures around average to mild.

Gonzo

GFS switches on the blowtorch for Christmas Day evening,





10C/11C at 5pm after dark.

Unlikely this will verify as we're so far out but every GFS run is completely different at this stage.

Artane2002

that GFS run can probably be binned, the expanse of the HP is hard to believe and that dartboard low makes the whole chart look even less plausible.

Gonzo

Artane2002 wrote: »

that GFS run can probably be binned, the expanse of the HP is hard to believe and that dartboard low makes the whole chart look even less plausible.

yep it's very much an outlier as well, most of the other runs are cooler and some are still very cold.

pauldry

By the looks of the GFS ensemble above it looks at the moment as if its all if in the air still.

Predictions for Christmas day anything from 0 to 15c. Does that mean it will be 7.5c

Gonzo

This mornings GFS run similar to the pub run yesterday except it's even warmer, pumping very mild air up from the Canarys over Ireland with daytime temperatures around 11 or 12C.