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

sdanseo

YanSno wrote: »

That's a messy looking output, sleet to snow then back to sleet

Unlikely that the cold pool would be quite as fragmented as shown, especially on the later chart. If we hang on to -6/-7 uppers or better, should be snow throughout surely.

+360hrs as well so any refinement like that will be totally different nearer the time

YanSno

sdanseo wrote: »

Unlikely that the cold pool would be quite as fragmented as shown, especially on the later chart. If we hang on to -6/-7 uppers or better, should be snow throughout surely.

+360hrs as well so any refinement like that will be totally different nearer the time

The fragmented cold is where the warm core probably would be located and with onshore winds it would be mostly sleet for the east cost.

kod87

YanSno wrote: »

The fragmented cold is where the warm core probably would be located and with onshore winds it would be mostly sleet for the east cost.

Maybe, maybe not, but it's so far out in FI that going into any detail on those charts is meaningless.

The only use for charts that far out is to see if any trend is developing and even then it is extremely unlikely.

Meteorite58

The GFS 18Z continues the colder theme. In general what I am seeing in the charts is potentially turning wintry at times. Bit of a mix of everything I would imagine. Rain fronts and sleet and possible wet snow on higher elevations , possibly in the W /NW /N more so , windy at times, quieter interludes, hail and possible sporadic thunder at times behind the fronts, cold frosty nights in sheltered areas , white peaks on mountains at times, dazzling sunshine , windchill and a stretch in the evenings ! Looking colder the further out with an increasing chance of some snowfall towards around +240hrs perhaps but this could be more so on elevated ground ?

Will be interesting to see if we get a front like what is showing up on the ECM around next Thurs or Fri . A rain belt running into cold air, a scenario like this could produce a brief dump of snow ( but upper temperatures might need to be a bit colder ) along the leading edge followed by sleet and rain. Snow possibly settling on high ground for a short time as warmer air follows behind.

Danno

Nice - widespread snow!

pauldry

This time next weekend the snowlercoaster will be going up the arc .... hope theres not a dip but the over 200hr consensus is cold. I think midweek is the last time we see 10c in January.

Meteorite58

ECM 0Z in general showing the temperatures cooler past +120hrs than previous runs. Even with the passage of fronts it shows upper temps in the main staying negative. Gets even more interesting from next weekend with what appears to be a slider low negatively tilted moving across Ireland around the early days of Mon- Weds week. Looks wintry. ECM showing possibility of snow at this early stage. No doubt changes can and will happen but i expect by this time next week the mild period in Dec /Jan will be well behind us as we adjust to proper winter weather.

squarecircles

atrocious 12z gfs


there i was in early december dreaming of an frosty cold janaury,ice days,dazzling sunshine and
snow showers.
so thats janaury done with
all thats left is february,wintry weather in march can f off.

next week looks a right pigs ear of a mess on the 12z gfs


nice and toasty on the west coast too,in double digits,plenty of pig muck ouzing
in off the atlantic followed periods of cold zonality, a wintry sloppy mess

Snowbiee21

squarecircles wrote: »

atrocious 12z gfs


there i was in early december dreaming of an frosty cold janaury,ice days,dazzling sunshine and
snow showers.
so thats janaury done with
all thats left is february,wintry weather in march can f off.

next week looks a right pigs ear of a mess on the 12z gfs


nice and toasty on the west coast too,in double digits,plenty of pig muck ouzing
in off the atlantic followed periods of cold zonality, a wintry sloppy mess

But we worent expecting anything next week really , wasn’t it all about the week after ajd possibly the first week into January ?

Andrew00

Outlook for January now is a small bit cold, but just your usual dirty Atlantic wind and rain

SleetAndSnow

Imagine being in Scotland

highdef

Precip charts for the GFS(P) are looking great for a potential decent snow event on Monday week.




Well into FI:

sdanseo

squarecircles wrote: »

atrocious 12z gfs


there i was in early december dreaming of an frosty cold janaury,ice days,dazzling sunshine and
snow showers.
so thats janaury done with
all thats left is february,wintry weather in march can f off.

next week looks a right pigs ear of a mess on the 12z gfs


nice and toasty on the west coast too,in double digits,plenty of pig muck ouzing
in off the atlantic followed periods of cold zonality, a wintry sloppy mess

Temps will struggle to get above 8c before Friday looking at the 12Z
It's wet muck alright but very fine margins for Thursday. -8 uppers and <528dm thickness for the North and East but probably only sleet and snow over higher ground. A small fluctuation though as has been mentioned is all it will take either way - 100% rain or 100% snow.

FI is 96-120hrs if even that right now.

That said lots of potential for week commencing 21st.

Rebelbrowser

Thoughts on the 12z ECM folks? I'm out of my depth analysing in current set up....

Cork Boy 53

SleetAndSnow wrote: »

Imagine being in Scotland

Those coldest temperatures are mainly in the Scottish highlands, mountain ranges etc,. Cold temperatures and wintry weather there at this time of the year is nothing out of the ordinary for them.

Artane2002

The GFS Parallel has a HUGE snow bias. When the UK had a freezing rain event last month it was showing widespread snow cover for Ireland and the UK (Ireland only had regular rain). And if there's showers that were 99% rain and 1% sleet it would show snow cover.

PukkaStukka

Cork Boy 53 wrote: »

Those coldest temperatures are mainly in the Scottish highlands, mountain ranges etc,. Cold temperatures and wintry weather there at this time of the year is nothing out of the ordinary for them.

I was in the Highlands for Hogmanay and it was very mild and dry. Only the very highest peaks had some snow but not that much either.

Cork Boy 53

PukkaStukka wrote: »

I was in the Highlands for Hogmanay and it was very mild and dry. Only the very highest peaks had some snow but not that much either.

Yes, but just as in Ireland, Scotland has had unseasonably mild temperatures for most of this winter up to now. Not the usual Highlands winter weather.

Meteorite58

ECM keeping the cold going out to the end of the run at +240hrs (would think the GFS is an outlier all right as it takes days for the ridge to get swept aside ). Difference in this run is that the slider low for Tues /Weds week on this run goes to dump a large amount of snow on the UK. Early days and changes to come but at present has a wintry look after next week end from around Tues.

ECM building a ridge up over Ireland but with cold uppers Mon week.

Will make all the difference where the cold is and how the low approaches and at what speed it is moving and if it stalls and and.......

Meteorite58

The GEM is more like the ECM but a bit less cold.

sryanbruen

https://twitter.com/MJVentrice/status/1084451477693841408

Meteorite58

GFS 18Z gone a bit bananas tonight showing a Low at 925hPa at +234 hrs . It is a bit all over the place atm but it may be adjusting to the extreme cold forecast for parts of the US / Canada and expected heavy snow there. It shows a very strong Jet coming out of the US next week . Wouldn't expect any storm like that but will be interesting to see how it evolves.





https://twitter.com/WinterExpert/status/1084542928868044800

Villain

AO and NAO trend today is nice, this could help make FI charts a little more interesting for the end of the month

https://twitter.com/Petagna/status/1084807557309480960

Snowbiee21

Villain wrote: »

AO and NAO trend today is nice, this could help make FI charts a little more interesting for the end of the month

https://twitter.com/Petagna/status/1084807557309480960

@yansnow

YanSno

Today Most ensemble members are on negative side by the end of January than 2 days ago. It's heading towards the right direction. Potential of a blocking but as always not definite

14/01/19 NAO


12/01/19 NAO

SleetAndSnow

From my still growing model knowledge, this is what I think the latest ECM shows but please correct me!

Ireland seems to be kept under cold uppers from tomorrow onwards really, which could end up being a shock to the system after the mild weather we have had. However as the model progresses we gradually get under colder uppers and it eventually shows a storm over Ireland around 216 hrs (below)



This storm looks pretty deep (but I am unsure as to if this would produce much snow for us, I am assuming it would be a moreso sleet/rain event with snow on higher ground?). The winds accompanying this storm could be strong as the isobars look pretty tight off the north coast eventually working their way down south meaning most of the country could feel this.(below)



It seems to be an all day storm with it moving south-eastwards across the country at 240hrs (below)


One thing this could do (hopefully) is draw colder air down from the north/northeast with it (but again just a guess im not certain!). I am assuming this will be a fairly cold storm should it come to be however. I don't think I remember the ECM modelling strong storms out in FI in my experience and having them disappear but again it is FI and could be gone next run (but I have a feeling it won't but it will be watered down quite a bit i am guessing!)

Please the more experienced people fix this post in any way necessary, just thought I would try and take a shot to see if I am starting to understand the models more after a year around here now

sdanseo

No chance of snow under that with just -4 uppers but if a 955mb storm that size crosses over Ireland and takes 24hrs to do so, snow (or lack thereof) will be the least of our worries!

sryanbruen

That ECM would likely bring some snow to usual higher ground though this would probably be limited with mostly rain or strong winds. It ends in a very amazing way that would be conducive to a blocked pattern with the Azores High retrogressing to the northwest and that low diving southeastwards to pull in a northeasterly flow. There's a deep cold pool waiting to be tapped into from that northeasterly at 240 hrs.

All just for fun though!

sdanseo

GFS-P still bringing widespread snow from around this time next week onwards. Still FI, but consistent now for 24hrs almost.

GFS Operational has a known bias towards snow when in fact rain is more likely especially at 96-144hrs sort of ranges. Next 3/4 days might be a good time to test to see if this is the case with the parallel as well.

gabeeg

sdanseo wrote: »

GFS-P still bringing widespread snow from around this time next week onwards. Still FI, but consistent now for 24hrs almost.

GFS Operational has a known bias towards snow when in fact rain is more likely especially at 96-144hrs sort of ranges. Next 3/4 days might be a good time to test to see if this is the case with the parallel as well.

Any idea if the parallel is as bad with precipitation as the operational?