FI Charts ( T120+ onwards) Winter 2018 / 2019 **READ MOD NOTE IN FIRST POST**

nacho libre

It's encouraging to see this given there was talk of 4- 6 weeks of Atlantic driven weather by some folks recently.

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Mod Note

This thread is for posting/discussing/analysing FI CHARTS ONLY i.e. Charts in the unreliable time frame, generally +T120 onwards

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Thanks

arctictree

GFS 12z returning to a very wintry theme from t+216 onwards.

Snowbiee21

arctictree wrote: »

GFS 12z returning to a very wintry theme from t+216 onwards.

Way too far to be getting hopes up, positive signs at least

JCX BXC

Completely different theme to the 06Z GFS, it's something to watch over the next few runs! I'd be weary though, it could dissapear just as fast as it came.

Good signs however, the GFS obviously thinking this has the potential to show up at some stage.

pad199207

The drop it and pick it back up again scenario/theme from the models is always one to watch in winter.

Gonzo

some wintry signals far out in FI, but with the Atlantic now powered up and charged to the max, I wouldn't be banking on wintry conditions this side of Christmas. Even if we get a shot at some cold, it probably won't last very long.

Artane2002

Gonzo wrote: »

some wintry signals far out in FI, but with the Atlantic now powered up and charged to the max, I wouldn't be banking on wintry conditions this side of Christmas. Even if we get a shot at some cold, it probably won't last very long.

I agree that it probably won't last long but I do see why there might be a brief cold shot. The teleconnections support a blocked pattern but the powerful jet isn't letting it happen now. There seems to be a gap between low pressures on each side of the Atlantic allowing the Azores High to be sucked up north in the charts. If the gap isn't big enough then we'll probably be stuck in this pattern for longer.

JCX BXC

The 18Z isn't as amazing but still seems to maintain the cold outbreak, just moving it a couple of hundred km to the east.

Meteorite58

ECM has been showing stormy weather over the last few runs for next Friday . Track has been changing not surprisingly this far out but showing very strong winds along Atlantic coastal counties especially the W and NW , and Northern counties. Chance of being a named storm but could drift further North also. A bit of a way to go to know for sure.

typhoony

gfs has been toying with the idea of an easterly blast then the followed by the PV heading south, of course it's all beyond the reliable timeframe but we should have reasonably clear picture in a few days time

Meteorite58

GFS 12Z looking cold

Meteorite58

Big difference between the ECM and GFS out at + 240 but the ECM trending a cold air mass moving across Europe from E to W

BLIZZARD7

ECM 00z building on the colder theme as we approach Mid-December -

typhoony

gfs 18z keeps on with cold theme as it builds a Scandi high, ecm 12z does it's best but just falls short. can we get enough cold air to the east

The12thMan

did someone say "Sudden Stratospheric Warming " (white christmass)

http://wxcharts.eu/?panel=default&model=gfs,gfs,gfs,gfs&region=polar&chart=10temp,surface_temp,snowdepth,850temp&run=06&step=384&plottype=5&lat=56.242&lon=-5.310&skewtstep=0

Snowbiee21

Destination Greenland is the message from the pub run

BLIZZARD7

Up she goes at 120-144hrs -



Easterly in place at days 7-8 with a building high to our north and the key low pressure belt building in over southern europe* - No ultra cold 850's as yet but the blocks are falling into place.



Expect run to run variation on the same theme post day 7- we need the majority of the EC suite to get on board to be sure the op runs have the right idea here.

No deep cold showing as yet but these are far from your average December charts - Scandi high controlling the scene for the foreseeable it would seem. Hopefully the atlantic lows all slide under.

Keep an eye on the key timeframe @ +120 to +168hrs on future model runs.

*This run doesn't quite get the required 'Genoa low' in place to sustain the pattern but there is plenty of time for that to occur still.

Meteorite58

KingdomRushed wrote: »

Looking like it’s going to be storm watch next week given the latest GFS output. Severe weather likely. A very violent depression showing for next Thursday.

3 out of 4 showing it over or near us this far out, one to watch, makings of unsettled weather the second half of next week and turning cold , ECM colder than GFS.

KingdomRushed

It is worth running through the GFS ensembles for 6z this morning. Most all of them have some form of low pressure system almost right over us next Thursday. A number of them show an absolutely vicious storm. The track of this is quite similar across a good proportion of the ensembles while the intensity differs.

Very interesting period of weather approaching. It’s going to be stormy I think we can almost say for certain but with current GFS forecasts showing these dartboard depressions running through Ireland rather than swinging N off the coast as often happens.

pauldry

They are bound to get one right eventually.

The last few storms have been nowhere near as vicious as the +144s showed originally.

Are they attention seeking or legit?

As said Id say very windy next week for sure.

Also if there is to be a vicious storm mid December would not be too unusual especially with the energised jet we are currently covered by.

nacho libre

pauldry wrote: »

They are bound to get one right eventually.

The last few storms have been nowhere near as vicious as the +144s showed originally.

.

The GFS are notorious for doing this most winters, as you say they are bound to be right at some stage, but i wouldn't take too much notice of their depiction just yet. If the UKMO and ECM start modelling a vicious storm to hit us, then i'd take heed. I have a feeling this storm will end up tracking well to the north west of Ireland, and affect parts of Scotland more so than us .

Artane2002

nacho libre wrote: »

The GFS are notorious for doing this most winters, as you say they are bound to be right at some stage, but i wouldn't take too much notice of their depiction just yet. If the UKMO and ECM start modelling a vicious storm to hit us, then i'd take heed. I have a feeling this storm will end up tracking well to the north west of Ireland, and affect parts of Scotland more so than us .

It's hard to take the GFS seriously right now. If the storm doesn't happen the way the GFS is showing then everything that follows the storm on the GFS will probaly be wrong.

Meteorite58

The chart MT was talking about for Monday week, what a stonker ! Of course out in FI so open to change but a good marker to see how the models are faring.

Models differ after about next Thurs but all showing an unsettled spell which will get more clear as the days go on, potential for wet and windy weather with a mix of cold and mild air going through associated with fronts.

Jet keeping S of us it seems steering in the weather in off the Atlantic .

Ensembles continuing to throw out some wild solutions.

Meteorite58

Yea GFS 18Z showing some very active weather through next weekend , both Fri and Sat into Sun , deepening storms impacting and penetrating far inland. But under the present weather setup this could all change in the next run


ECM showing a storm off the Atlantic coasts on Fri and another deepening low Sat but that one not impacting Ireland , moving over the UK instead. No sign of the Storm positioned over Ireland for next Monday which was showing on the last run, just shows how changeable the charts are.

GEM very similar to the ECM with a Storm off the W coast Fri keeping strongest winds along the coasts and the second system on Sat bombing as it deepens on a track over Southern uk.

To note two days ago most models were showing a storm very near Ireland for this Thurs, this stayed well out to sea with the fronts just making it over us .

Very unpredictable towards the end of the week, very strong jet nearby will keep the models and forecasters busy.

JCX BXC

If only this chart wasnt +384

Meteorite58

GFS has remained somewhat similar to yesterdays run with two vigorous systems next Fri and Sat ( on this run they remain just off the coasts ) . Gem now more like the GFS, ECM showing very stormy conditions on the W coasts next Sat.

So chopping and changing but a trend of unsettled weather next weekend and possibly stormy at times.

Meteorite58

All new looking charts again this evening from the ECM, hardly worth putting up they are changing so much . ECM showing the risk of storms receding this weekend, windy and wet. The Farming forecast showing very wet in the SW and NE this week from slow moving fronts that come up against Hp in Europe helping to block and stall them as they move slowly over Ireland . Met Eireann showed 100 mm possible in Valentia by the weekend . Still a big uncertainty how it pans out after Thurs.

Meteorite58

The GFS and ECM like chalk and cheese Fri and Sat coming. GFS bringing a Low close to Ireland on Fri and on Sat a very severe deep low with the strongest part of it moving up over Ireland , interesting that the GEM looks very similar to the GFS.

We shall see , long way off yet , now if the ECM was showing the same.....


Tropical Tidbits.Com

icesnowfrost

Something to drool over. It’s not perfect but it’s good to see. I slight shift to the west with them uppers.

BLIZZARD7

Not bad for a mean chart @ +180hrs when you consider a lot of the suite have those lows over us sliding more to our south, there's definitely a wintery outcome possible over the Christmas period- as ever, time will tell. These means may actually be useless if the op runs lead the way here. The models haven't got a grip on the situation yet and this will likely get worse as the strat warming comes into play.

Meteorite58

GFS out in FI showing Atlantic mixed with unsettled cold wintry outbreaks from the NW /N . The Jet, according to the GFS, looks to take a more Southerly route in general below Ireland letting colder air sink down over us.

ECM out to +240 in general looks colder than this week with a milder interlude associated with fronts going through towards Fri 21st.

icesnowfrost

Things still looking good for Christmas Day but way out into FI

dacogawa

I'll just leave this here...

squarecircles

KingdomRushed

Hmmm bit of interest suddenly with GFS going for GL blocking on the 6z, and a similar theme but a lot messier on its sister model the GFS parralel

Captain Snow

Interesting from Christmas eve onwards ....
Seasonal for sure :eek:

Meteorite58

Well the cold might get there for the 25th going by the ECM and GFS. GEM different story.

Reversal

Just for fun.. couple of GEFS members starting to something other than Atlantic drivel...

Chris_5339762

1065mbar!!!

sryanbruen

With a significant stratospheric warming incoming next week onwards, the model output should become crazy for the New Year with lots of different solutions being generated as they get to grips with tropospheric impacts from the event.

We saw from last February the kind of impacts a sudden stratospheric warming (SSW) event can deliver to the troposphere if it fully propagates and evolves in the way it did from a displacement to a full on split of the Polar Vortex. This December 2018 event is going to be a displacement but some outlooks show the possibility of this becoming a split in early January 2019 including the ECM and UKMO Glosea5 though the latter we do not have access to for stratosphere data and can only go off of snippets given on Twitter occasionally. We will have to see if it evolves into a split as we get closer to that timeframe. If I were to guesstimate, I'd say a split has a reasonable chance with record breaking heat flux being transported into the stratosphere. In case you do not know, heat flux is heat transported from the tropics to the poles by weather systems. This heat is propagated up to the stratosphere and results in "waves of warmth" which disrupt and or weaken the stratospheric Polar Vortex. Sometimes this warmth can propagate back to the troposphere and do the same to the tropospheric Polar Vortex. That's the basic definition of it, there's another level of complexity involved but I won't get into that! This heat flux should in theory intensify any stratospheric warming events in the New Year and result in a split of the Polar Vortex but as ever with weather, there is no guarantee. During the next two to three weeks starting next week, do not expect the model output to be the greatest with lots of flips and flops as a result of this warming in the stratosphere (though it hasn't really been great since the end of the May/June warm spell). We should know this well by now given what we had pre-the Beast from the East earlier this year. Remember that splits tend to have quicker tropospheric responses than displacements.

In terms of latest output, Christmas Day looks mild and settled with a lot of cloud around. On the GFS, the high is positioned more over top of the country attempting to retrogress to Greenland where there is a weak ridge but by the end of that week, the high gets pushed into the Mediterranean as low pressure systems gang up in the Atlantic. Initially, one would think this is a sign of an Atlantic onslaught. Whilst it does look like the signal is getting more unsettled as time goes on, the fronts look rather weak to me which would really only deliver a lot of cloud and patchy to light rain for the majority of places. If the high proves more stubborn than the model is showing right now, I think there'd be some instances of temperature inversions. This means that upper air layers would look mild, for example 850hPa, on charts with their temperatures. However, the surface would be chilly under high pressure with mist and fog occurring at times. This is more likely in the UK due to more runs and charts showing the high pressure is going to be centred around the east of the UK or southeast following Christmas Day.





The GEFS for Dublin look mild in terms of 850hPa temperatures with a dry Christmas Day and St. Stephen's Day but becoming more unsettled from December 28th onwards albeit quite weak rainfall signals with not a lot expected. Remember that if high pressure lies around longer than the operational run is suggesting, we could have some temperature inversions with the surface more chilly than what the 850hPa temperatures would suggest. When I say chilly, I mean temperatures in the mid single figures (slightly below average) so nothing overly cold.



The ECM shows the high pressure centred further to the southeast of the UK on Christmas Day than the GFS which leaves Ireland in a mild southerly flow on the western flank of the high. This would bring drizzle to localised parts of the country and temperatures in the double figures under a lot of cloud.





My Winter forecast released on November 27th suggested a mild and wet December which has verified very well. It also showed a chilly and blocked January with a lot of dry weather. There was the small risk of quite a wintry January although my analogues highlighted a severe January to come (which I did not rate highly at all). Going by the UKMO and the EPS, my forecast is not looking too far fetched for January (so far).

Overall, quite a benign outlook for the end of 2018 with some dry weather expected around Christmas Day as high pressure ridges in. Different positioning of the high pressure on models will determine how mild it gets. Some more unsettled weather possible during late December but far from a washout.

If the Polar Vortex does end up splitting in early January, I'd expect some tropospheric responses start to showing on models around the second week of the month minimum with blocking over Greenland/Scandinavia. However, that's highly speculative. Focus on the here and now. Model output is going to be useless generally for the next two to three weeks.

United road

Sryan, thanks for detailed update!
Fantastic stuff, your December has been as you suggested, so bodes well

No idea how old MT is, but his ready made replacement is already waiting to step up!!

Artane2002

To expand on what Sryan was saying about random model solutions, the GFS 12z shows a cold easterly with snow showers for the east coast and -11c uppers getting into the southeast for the first few days of January. Not gonna happen but it shows the randomness of the output... from very mild to very cold.

Widdensushi

How does between Christmas and New year look? Thanks in advance if anyone answers.

pauldry

A good deal of dry weather

Bland and mild some drizzle

Not the rainfest of recent weeks

Temps 6 to 10 or 11c

gabeeg

GFS Para. Way off. Probably nonsense. But still, nice to see

Meteorite58

Hp looks like the trend for awhile.

Donegal Storm

Has to be amongst the least inspiring autumn/winters in recent memory in terms of interesting weather, personally don't think I've experienced a single day of interest since the heatwave ended in July, just endless damp greyness!

No thunder or lightning, no impressive wind or rain, no real cold and only a small handful of sunny days. I find my tolerance of cold winter starts to wear thin by late January so hopefully we'll see something early in the new year

Meteorite58

Is that what ye were looking for lads

JCX BXC

Takes a while to get there no doubt!

Captain Snow

Into January....

Hopefully as the Strat warming takes effect we will see soon it showing up the runs.



Otherwise...….