Charts ( Up to T120 ) Winter 2020 ** READ MOD NOTE IN FIRST POST**

Meteorite58

Yeah ARPEGE on it too, ECM showing it for early Tuesday morning and keeping the snow for further N.

Meteorite58

Models have eased off big time on snow potential over the coming days, a bit wintry in Northern counites that's all .

Under the influence of Lp systems ,looks quite wet over the coming days.

After a milder few days for most looks set to turn colder again around Thurs /Fri.

Nqp15hhu

Latest ICON run is terrible. Low pressure heading NE and moderated cold air coming down afterwards, the prior run had the low running SE.

If this cold doesn't materialise in the next week, i'm moving on from this. We're just not far enough north this year, the cold is all up in the north of Scotland, and we're getting the scraps when the jet decides to orientate favourably for a day or two.

Even then it's only 2-3c.

SeaBreezes

ECM has flipped this morning!! All aboard the snow train

Interesting wind direction on those runs this morning
The cold is taking a south of east route in,yet still has that -10 to -11 uppers profile as the source is the same
That fetch would put a lot of cork especially near the coast,waterford and wexford in play for some very very heavy snow showers ,just 1 week from now

Gonzo

A big change is on the way to our weather over the next few days. We've had what seems like almost constant rain and wet conditions over the past 5 days in what has been an extremely wet and Atlantic dominated period of weather.

From tomorrow we should see a big reduction in the amount of persistent rainfall, this will be most welcome as it will allow the land to dry out a little bit and become less saturated.

It won't be completely dry however, a mixture of cloud and showery outbreaks of rain at times on Thursday but amounts will be nothing like the deluges we have seen over the past week. Temperatures will be close to normal between 6 and 8C.

Friday will begin a cooling trend, some showers across western regions which could be wintry on hills. These will die out as a northerly wind sets in. Showers will continue along northern coastal areas and may start to fringe against eastern coasts on Friday night. Friday will feel quite chilly with temperatures ranging 4 to 8C. These showers mainly of cold rain. There may be a light frost in a few sheltered spots Friday night.



Saturday will be a mostly dry day but rain showers will begin to pepper eastern coastal regions. These could band together at times to produce rather wet conditions in a few places.





Saturday night will turn fairly cold especially across the west with a ground frost in many areas. Eastern areas will be milder due to a stiff onshore easterly wind and rain showers at times, these will gradually turn more wintry later in the night towards Sunday morning.

Sunday will be colder again with some very cold air beginning to track east to west. Sunday will be a mostly dry day but some wintry showers of rain, sleet and wet snow will drift into some northern and eastern areas. These could be rather light and patchy in nature to begin with. Temperatures on Sunday generally between 1 and 4C.



Sunday night will be very chilly with a widespread frost. Mostly dry but some light wintry showers along eastern coasts may become more widespread and heavier across Leinster, by this stage many of them will be turning to sleet and snow with some light coverings possible to low levels.Temperatures Sunday night between 0 and -3C.

I shall go no further than this, just firming up on the weather between now and the beginning of possibly the coldest period of weather we've seen since March 2018. The reduction of rainfall over the next few days will be most welcome, however it won't be completely dry either. temperatures gradually getting colder by a degree or so each day.

Meteorite58

For the SW and S will be keeping an eye on how close that area of LP will get on Tues , UKMO further away than the ECM, ICON closer again cliping the SW corner which would bring in wintry weather and snow possibility but no where certain, could be very weak. GFS tracking furthest away. For now just observing and will see how it progresses . Very cold day barely getting above freezing for many inland.

Gonzo

We still look on for a 3 to 4 day cold spell. Alot of negativity in here today and not sure why. This spell has never locked in 5+ days of cold and snow at any point, sure a few of the models have tried to extend it to next weekend but that doesn't mean it's going to happen. Same with the rapid breakthrough of the Atlantic and mild, it is not set in stone either. There are still disagreements between the models and alot of variations so the models are clearly struggling to get to grips with the very mild vs very cold battleground.

Most people will be happy with dryer conditions ahead of us, it sure is a break from the slate grey skies, rain and damp conditions of the past week. There will be frosts and sunny skies as well as snow showers at times. This event should not be compared to Storm Emma, it's nothing like that and should not be compared to December 2010 either. This will be a welcome spell of winter for a few days at least and is better than anything we've seen over the past 2 winters. Just don't expect snow by the meter, that is very unlikely to happen.

Expect more downgrades and upgrades between now and Sunday, this rollercoaster still has some way to go. Don't be focusing on snow depth charts this far out, the models are very poor at handling streamers inland, particularly for Ireland. I remember in the days leading up to December 2010, the models weren't exactly generous with the streamer potential and we ended up with 2 foot of snow. Not saying that we will get anything like that this time around but parts of Leinster, the midlands, maybe the south coast and parts of Ulster could see low to moderate falls of snow, certainly more than a bare dusting. It may not last a week like everyone wants but 2 to 3 days of watching the radar for showers and lamp post watching is better than none at all.

Meteorite58

Beginning of the slow cool down now, got up to 11.0c here in Tralee today but only looks abot 7.0C or so tomorrow , colder again on Saturday and beginning to see frost in places, first big frost setting in early Sun night.

Calibos

I'm not so much downbeat tonight about the 3-4 day duration the models are coalescing on, but the fact that it seems even the Mon/Tues Snow is looking like coming from a Easterly or South Easterly direction which takes Wicklow out of the game for the most part due to the Wales Shadow. ie. Can't look forward to a Frontal event on Wednesday anymore apparently and now neither does it look like I can look forward to much of anything except cold on Mon/Tues.

Meteorite58

Will be interesting to see how much streamer activity there is in the early days of next week and how far in land it might travel. Fair difference between SST and 850 hPa temps.

Calibos

Meteorite58 wrote: »

Will be interesting to see how much streamer activity there is in the early days of next week and how far in land it might travel. Fair difference between SST and 850 hPa temps.

Ah here! I thought GL on the other thread just said Easterlies on the cards now favouring Dublin, Meath and Louth meaning anything due west of Anglesey or South are out of luck. Yet those charts indicate the ENE I was hoping for and thought I was getting up til GL's latest post.

I can't keep track of all these different charts and chopping and changing.

JCX BXC

Calibos wrote: »

Ah here! I thought GL on the other thread just said Easterlies on the cards now favouring Dublin, Meath and Louth meaning anything due west of Anglesey or South are out of luck. Yet those charts indicate the ENE I was hoping for and thought I was getting up til GL's latest post.

I can't keep track of all these different charts and chopping and changing.

And they'll continue to chop and change! The joys of weather chart watching huh!

Gaoth Laidir

Calibos wrote: »

Ah here! I thought GL on the other thread just said Easterlies on the cards now favouring Dublin, Meath and Louth meaning anything due west of Anglesey or South are out of luck. Yet those charts indicate the ENE I was hoping for and thought I was getting up til GL's latest post.

I can't keep track of all these different charts and chopping and changing.

I took one point in time (next Tuesday). There will be some toing and froing between easterly and northeasterly before turning more southeasterly towards Thursday. And don't take the surface wind charts as steering flow.

Don't be expecting large totals from streamers. Convection will be fairly shallow and showers will be fairly shifting in the flow. I still worry about low-level moisture after the recent rain and saturated ground. A delicate balance of everything.

Rougies

Calibos wrote: »

Ah here! I thought GL on the other thread just said Easterlies on the cards now favouring Dublin, Meath and Louth meaning anything due west of Anglesey or South are out of luck. Yet those charts indicate the ENE I was hoping for and thought I was getting up til GL's latest post.

I can't keep track of all these different charts and chopping and changing.

Relax. The general trend in wind direction as the cold kicks in will be from the ENE* at first to E to SE over the course of 3/4 days. It's too far out to be looking at exact wind trajectory details. Everyone near the east coast is in with a shot, we'll have a much better idea on who is in favourable zones by Saturday. And then it will go down to a nowcast.

Gonzo

Calibos wrote: »

I'm not so much downbeat tonight about the 3-4 day duration the models are coalescing on, but the fact that it seems even the Mon/Tues Snow is looking like coming from a Easterly or South Easterly direction which takes Wicklow out of the game for the most part due to the Wales Shadow. ie. Can't look forward to a Frontal event on Wednesday anymore apparently and now neither does it look like I can look forward to much of anything except cold on Mon/Tues.

This is a constant struggle with everyone who lives near the east coast. Through the years I've had more than my fair share of disappointments with the Isle Of Man shadow. Every easterly that has delivered snow I get stuck under it at some point, sometimes I'm stuck under it the entire time and there is nothing I can do about it except hope for a variable wind direction.

During December 2010 I got caught under the shadow regularly while Dublin Airport not too far away was away from the shadow more often. There was a variable wind direction so when I was lucky to move away from the shadow the snow delivered alot in a short space of time.

The BFTE had me under the shadow almost the entire time. I remember the event started on a Tuesday and we had a few initial light showers and then nothing on Tuesday night, all of Wednesday and then Storm Emma began Wednesday night and that delivered.

A few days ago it was looking like I was going to be under the IOM and Ulster shadow based on the wind direction, that has now shifted to a wind direction much more favourable for my location. This event is still 2 to 3 days away and there is every chance this wind direction will shift again and it will also be variable. There is every chance we will all be under a shadow at some point, such is the joys of trying to juggle being away from the Ulster, IOM and Wales shadow.

This is probably part of the reason why models really struggle with streamers for Ireland, our coastline is full of shadow zones unlike the UK east coastline which has 100s of km of sea.

Nqp15hhu

The idea of a “shadow” in limiting precipitation is a very strange phenomena. When we get northerlies here, the showers generally come right down across the breadth of the north coast and we have no such “shadow”.

We are closer to Scotland than you are to the Isle of Man too. Very odd.

Danno

Nqp15hhu wrote: »

The idea of a “shadow” in limiting precipitation is a very strange phenomena. When we get northerlies here, the showers generally come right down across the breadth of the north coast and we have no such “shadow”.

We are closer to Scotland than you are to the Isle of Man too. Very odd.

The Pennines in England "dry out" the air in an easterly based convective flow. Once the easterly based flow returns out over the open water of the Irish Sea, it begins to pick up moisture causing convection to build and bring showers onto the east coast of Ireland from South of the Ards Peninsula right down to Waterford.

In your part of the world, an NE or E would have the Scottish Mountains or the Scottish Southern Uplands to dry out an airflow from those directions. However an ENE might manage to make it through the narrow "central belt" of Scotland between the two aforementioned terrains. The narrow strip of water between Ayr in Scotland and the north Antrim coast might just sustain showers in such a flow.

The east coast of England usually does well with a long sea-fetch to Denmark and the North Sea being less influenced by the warm Atlantic drift, however as you get right down into the SE of England and southern East Anglia, streamers are less intense owing to the shorter sea track to Holland.

Geography has a huge and profound effect on weather when it gets into a rut/pattern. In a northerly, you have a long sea track, so showers survive the short journeys over the scattered islands off West Scotland. The Isle of Man in the Irish Sea acts like an extension of the Cumbrian Fells mountain range and thus "blocks" convection from taking root.

JanuarySnowstor

Poor gfs run this morning. Brings in the low quicker and by Wednesday evening the cold uppers are lifting out.
Also brings the Tuesday low very close to the South which could kill off convection while it goes under?
UKMO as you were really but hardly an upgrade.
It sure will be a downer if we just get 3 days out of this but time for changes...

Rebelbrowser

JanuarySnowstor wrote: »

Poor gfs run this morning. Brings in the low quicker and by Wednesday evening the cold uppers are lifting out.
Also brings the Tuesday low very close to the South which could kill off convection while it goes under?
UKMO as you were really but hardly an upgrade.
It sure will be a downer if we just get 3 days out of this but time for changes...

JS I really, really don't understand this viewpoint given your predilection for cold and snow. We are in Ireland. Most years we don't get snow or nothing to speak of. This year most of us have had some already. There are now at least 3 days of potential snow showers just 48 hours away. All models show this. How in the name of God is there anything, literally anything , disappointing about that? If I get lying snow for 3 days it can be 26c on Thursday for all I care.

esposito

Rebelbrowser wrote: »

JS I really, really don't understand this viewpoint given your predilection for cold and snow. We are in Ireland. Most years we don't get snow or nothing to speak of. This year most of us have had some already. There are now at least 3 days of potential snow showers just 48 hours away. All models show this. How in the name of God is there anything, literally anything , disappointing about that? If I get lying snow for 3 days it can be 26c on Thursday for all I care.

Too many folk on here look past T120 on the models (me included) That’s the one negative of model watching. We sometimes fail to see the positives in the short term. Let’s enjoy and hopefully cherish these 3 or 4 days of proper cold and snow flurries/showers.

munsterlegend

Rebelbrowser wrote: »

JS I really, really don't understand this viewpoint given your predilection for cold and snow. We are in Ireland. Most years we don't get snow or nothing to speak of. This year most of us have had some already. There are now at least 3 days of potential snow showers just 48 hours away. All models show this. How in the name of God is there anything, literally anything , disappointing about that? If I get lying snow for 3 days it can be 26c on Thursday for all I care.

He posted that just before 5am. Also he hadn’t seen the ECM which delays the onset of milder weather.

Rebelbrowser

munsterlegend wrote: »

He posted that just before 5am. Also he hadn’t seen the ECM which delays the onset of milder weather.

Hadn't spotted that. Easy to be cranky at that hour I suppose!

In a nutshell
Very cold sunday-weak wintry streamers
Mon-wenesday increasingly heavy streamers for many but not all
Some seeing several cm's/white outs/temporary blizzards
Ice days probable for some
Pot luck as to who sees little or none in the favoured areas
Spell of continuous snow possible for many Thursday that could stall leaving some under heavy snow for several hours under a front that may not actually progress fully through meaning rain on its southern side or a thaw for all but this is unresolved as its FI still (but a likely outcome)
What the **** are people complaining about?

mcburns07

AuntySnow wrote: »

In a nutshell
Very cold sunday-weak wintry streamers
Mon-wenesday increasingly heavy streamers for many but not all
Some seeing several cm's/white outs/temporary blizzards
Ice days probable for some
Pot luck as to who sees little or none in the favoured areas
Spell of continuous snow possible for many Thursday that could stall leaving some under heavy snow for several hours under a front that may not actually progress fully through meaning rain on its southern side or a thaw for all but this is unresolved as its FI still (but a likely outcome)
What the **** are people complaining about?

Friday :pac:

Kermit.de.frog

AuntySnow wrote: »

In a nutshell
Very cold sunday-weak wintry streamers
Mon-wenesday increasingly heavy streamers for many but not all
Some seeing several cm's/white outs/temporary blizzards
Ice days probable for some
Pot luck as to who sees little or none in the favoured areas
Spell of continuous snow possible for many Thursday that could stall leaving some under heavy snow for several hours under a front that may not actually progress fully through meaning rain on its southern side or a thaw for all but this is unresolved as its FI still (but a likely outcome)
What the **** are people complaining about?

Indeed, the potential intensity of those showers is increasing.

Reckless Abandonment

Gfs 6z has Wednesdays low a bit more to the south at 108

KingdomRushed

The GFS 6z is a slight upgrade. It has the second low a tad weaker and perhaps a slightly higher pressure around greenland. It is suggestive of a few more hours of deep cold, perhaps into Thursday morning. Only tiny adjustments are required to make a 3 day cold spell into a 5 day.

BullBauld

AuntySnow wrote: »

In a nutshell
Very cold sunday-weak wintry streamers
Mon-wenesday increasingly heavy streamers for many but not all
Some seeing several cm's/white outs/temporary blizzards
Ice days probable for some
Pot luck as to who sees little or none in the favoured areas
Spell of continuous snow possible for many Thursday that could stall leaving some under heavy snow for several hours under a front that may not actually progress fully through meaning rain on its southern side or a thaw for all but this is unresolved as its FI still (but a likely outcome)
What the **** are people complaining about?

How far inland do you think the streamers will get... basically is Roscommon a possibility?

Reckless Abandonment

Gfs 6z carry on the same theme. Cold and snowy mainly in the east. Breakdown from Thursday.