Cold Spell - Feb 7th to 13th 2021 - Technical Discussion

Humberto Salazar

Slashermcguirk wrote: »

Met Éireann update going for big accumulations for north and east up to Friday morning

Nope.

nacho libre

sryanbruen wrote: »

They do BB for their extended. It was funny a week ago when they used that single ECM outlier showing a long fetched mild southwesterly airflow for 10 February. That worked out for them...

Also the UKMO provide them with information for potentially impactful events. So they were likely using them this week.

KingdomRushed

Even 48 hours ago there was potential showing for massive dumpings of snow between Thursday and Saturday. There is no dressing it up that this is all but evaporated now, with the final straws being clutched now dissolving - ie Met Eireann issuing a yellow warning for up to 5cm of snow, paltry, anemic outcome, that says it all really.

In all my years weather watching I have never seen such a pathetic outcome from such superb looking synoptics. A double bust, an easterly in place with a direct feed of uppers sub minus 8 producing intermittent graupel, and a breakdown which promised significant frontal snow now likely lasting no more than a few hours and reducing in projected intensity by the minute. It just goes to show you never know until you know, ha ha ha.

Kermit.de.frog

I guess for most the issue is not so much Thursday night/Friday when most will see some snow at this stage (just a question of how much) but rather what is the point if it's going to be washed away within 36 hours.

That's not nailed yet but it's close to it.

Let's see what this evening model output shows before all the toys go out of the pram

pad199207

How is this good for anyone’s health honestly?

bazlers

KingdomRushed wrote: »

Even 48 hours ago there was potential showing for massive dumpings of snow between Thursday and Saturday. There is no dressing it up that this is all but evaporated now, with the final straws being clutched now dissolving - ie Met Eireann issuing a yellow warning for up to 5cm of snow, paltry, anemic outcome, that says it all really.

In all my years weather watching I have never seen such a pathetic outcome from such superb looking synoptics. A double bust, an easterly in place with a direct feed of uppers sub minus 8 producing intermittent graupel, and a breakdown which promised significant frontal snow now likely lasting no more than a few hours and reducing in projected intensity by the minute. It just goes to show you never know until you know, ha ha ha.

Couldnt agree more its the GOAT of all let downs.

nacho libre

In some areas the snow will do well to last more than 6 hours. It's very unlikely we will see a massive flip back to what was showing yesterday. I will be more than happy if the models tonight prove me wrong !

tomcosgrave

bazlers wrote: »

Couldnt agree more its the GOAT of all let downs.

It's the Kouhoutek of Irish winter weather watching!

hatrickpatrick

Is anyone else finding it unimaginably frustrating to have had such seemingly epic synoptics leading into this and now feeling like it's all sort of melting away, pun intended?

bazlers

I would prefer the slate wiped clean now and hopfully get a few days prope snow late February and then let Spring, spring.

Cw85

hatrickpatrick wrote: »

Is anyone else finding it unimaginably frustrating to have had such seemingly epic synoptics leading into this and now feeling like it's all sort of melting away, pun intended?

Its the same nearly every year. I always get so built up watching the charts and following the thread on here but more times that not it's a letdown and 8 always say I'm not following these threads anymore, but here I am

Kermit.de.frog

Let's hope the GFS has the best grasp of this. Very consistent.

ninebeanrows

The snow risk seems to have transitioned into more a risk for flooding in the south and west this weekend!

I've given up on long-term model watching. It just sucks all the joy out of the weather for me. I'm only 40 but there was a lot to be said for, back in my early days of weather obsession, the farming weather on a Sunday being the only long-term forecast, and then just getting the three-day weather each evening after the news. The models make a lot of promises they are never going to deliver given the precarious nature of where we are located, and they leave a lot of people disappointed and annoyed.

yorlum11

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Looks like the Southeast could do ok. It will probably change. Back to ran Friday night/Saturday on current guidance.

DOCARCH

Mod Note: Some 'non technical' posts moved to https://www.boards.ie/vbulletin/showthread.php?t=2058155857

Chin up everybody!

Villain

Some good news and some bad news!

The good news is the ECMWF 6z model shows cold hanging in longer:


Charts for 6am Friday

00z:


06z:


However it also stops the front dropping much snow further Northeast!

00z:


06z:

compsys

Deleted User wrote: »

I've given up on long-term model watching. It just sucks all the joy out of the weather for me. I'm only 40 but there was a lot to be said for, back in my early days of weather obsession, the farming weather on a Sunday being the only long-term forecast, and then just getting the three-day weather each evening after the news. The models make a lot of promises they are never going to deliver given the precarious nature of where we are located, and they leave a lot of people disappointed and annoyed.

Yes, I've said many times that the overabundance of data that we have can be a hindrance sometimes: numerous models, ensemble forecasts, precipitation charts, SSW data, wind speeds, dew points. It's endless.

I mean had this been 30 years ago all we'd have had to rely on was the MET E forecasts, which haven't been that wide of the mark.

It's we, ourselves, in here who have hyped things up a bit too much (as well as the media of course).

It doesn't help that, through social media in particular, it's so easy to see where else is getting snow so you feel even more hard done by.

I'm still hopeful for something on Thursday for the east at least. However I fear if the cold block hangs on it'll just suck the life out of the front.

Elmer Blooker

KingdomRushed wrote: »

Even 48 hours ago there was potential showing for massive dumpings of snow between Thursday and Saturday. There is no dressing it up that this is all but evaporated now, with the final straws being clutched now dissolving - ie Met Eireann issuing a yellow warning for up to 5cm of snow, paltry, anemic outcome, that says it all really.

In all my years weather watching I have never seen such a pathetic outcome from such superb looking synoptics. A double bust, an easterly in place with a direct feed of uppers sub minus 8 producing intermittent graupel, and a breakdown which promised significant frontal snow now likely lasting no more than a few hours and reducing in projected intensity by the minute. It just goes to show you never know until you know, ha ha ha.

You can never depend on a Scandinavia high to deliver in winter.
In 1987 an epic Siberian blast went out with a whimper when the high sank and we ended up with a Euro high.
In the 2018 BFTE the Scand high seemed to disappear in the blink of an eye - one minute it was there and then all of a sudden the block was gone ended and up over north Canada.
Now its looking likely (I'd love to be wrong) that the block to the east won't be far enough north.
It seems getting everything to fall into place is the equivalent of a nine dart finish or a 147 break! .... or Leicester winning the PL.

pad199207

Villain wrote: »

Some good news and some bad news!

The good news is the ECMWF 6z model shows cold hanging in longer:


Charts for 6am Friday

00z:


06z:


However it also stops the front dropping much snow further Northeast!

00z:


06z:

I’d give up that frontal snow just to get the cold to stay in longer

nacho libre

pad199207 wrote: »

I’d give up that frontal snow just to get the cold to stay in longer

But it's kind of pointless when the next push will bring in milder weather anyway. So we get a slight delay, but without a decent snowfall due to the front decaying. We need a big upgrade tonight, but rarely when there has been a sudden flip at this range to a milder outlook, do the models flip back the other way.

munsterlegend

nacho libre wrote: »

But it's kind of pointless when the next push will bring in milder weather anyway. So we get a slight delay, but without a decent snowfall due to the front decaying. We need a big upgrade tonight, but rarely when there has been a sudden flip at this range to a milder outlook, do the models flip back the other way.

These Atlantic fronts never bring anything worthwhile. It’s usually a sloppy mess and reintroduction of much milder weather.

nacho libre

munsterlegend wrote: »

These Atlantic fronts never bring anything worthwhile. It’s usually a sloppy mess and reintroduction of much milder weather.

Yes. We needed the airmass to be colder than it is and for the cold to be well entrenched, but even then as you say the milder air usually win out, except for those rare 1947 type situations.

Slashermcguirk

Update just now from met Éireann

NATIONAL OUTLOOK

Overview: Remaining cold and unsettled with more widespread falls of sleet and snow. Becoming windy over the weekend with spells of rain, possibly falling as snow in the eastern half of the country.

Wednesday night: Largely dry, cold night with isolated wintry showers and clear spells. However rain, sleet and snow will move into the southwest overnight as southeasterly breezes freshen. Winds will become strong and gusty across the southwest. Lowest temperatures of -4 to +1 degrees with frost and ice forming, coldest in Ulster.

Thursday: Sleet and snow will slowly extend northwards from the southwest across much of Munster, Connacht and Leinster, with snow accumulations leading to hazardous conditions. Highest temperatures of 1 to 3 degrees. Feeling colder in fresh and gusty southeast winds, strongest in western and southwestern counties.

Thursday night: Remaining breezy overnight with sleet and snow continuing to fall over much of the east, midlands and north leading to further accumulations. However, precipitation will turn to rain in parts of the south and west. Lowest temperatures of -1 to +2 degrees with fresh southeasterly winds.

Friday: Some lingering falls of sleet and snow in the eastern half of the country, with outbreaks of rain elsewhere. More persistent rain will move into western counties during the evening. Southeast breezes will strengthen during the day, becoming strong and gusty in coastal counties. Highest temperatures generally of 1 to 4 degrees, however less cold in southwestern counties with highs of 5 to 8 degrees.

Friday night: A wet, windy night with rain turning to snow over the north, east and midlands, leading to some accumulations. Cold night for many, with lowest temperatures of -1 to +2 degrees however much of Munster and southern Connacht will be less cold with lows of 4 to 7 degrees. Fresh to strong and gusty southeast winds.

Saturday: Windy with outbreaks of rain, possibly continuing to fall as sleet and snow in Ulster and north Leinster for a time. Southeast winds will be fresh to strong and gusty. Remaining cold across the north, east and midlands with highest afternoon temperatures of 1 to 5 degrees, a few degrees milder elsewhere. Windy overnight with further falls of rain, heavy in places, possibly turning wintry in parts of the north and east. Lowest temperatures of 0 to 4 degrees, with milder conditions persisting in the southwest.

Current indications suggest Sunday will remain unsettled with breezy conditions and further rainfall. Some uncertainty regarding temperatures, with a possibility of colder and wintry conditions persisting in eastern areas.

Gaoth Laidir

This morning's sounding from Aberporth, SW Wales, shows just how little instability there is. Both 850 and 700 hPa levels are at -10 °C. That's a 1.5-km layer in which the temperature didn't fall at all with height.

TTLF

Slashermcguirk wrote: »

Update just now from met Éireann

NATIONAL OUTLOOK

Overview: Remaining cold and unsettled with more widespread falls of sleet and snow. Becoming windy over the weekend with spells of rain, possibly falling as snow in the eastern half of the country.

Wednesday night: Largely dry, cold night with isolated wintry showers and clear spells. However rain, sleet and snow will move into the southwest overnight as southeasterly breezes freshen. Winds will become strong and gusty across the southwest. Lowest temperatures of -4 to +1 degrees with frost and ice forming, coldest in Ulster.

Thursday: Sleet and snow will slowly extend northwards from the southwest across much of Munster, Connacht and Leinster, with snow accumulations leading to hazardous conditions. Highest temperatures of 1 to 3 degrees. Feeling colder in fresh and gusty southeast winds, strongest in western and southwestern counties.

Thursday night: Remaining breezy overnight with sleet and snow continuing to fall over much of the east, midlands and north leading to further accumulations. However, precipitation will turn to rain in parts of the south and west. Lowest temperatures of -1 to +2 degrees with fresh southeasterly winds.

Friday: Some lingering falls of sleet and snow in the eastern half of the country, with outbreaks of rain elsewhere. More persistent rain will move into western counties during the evening. Southeast breezes will strengthen during the day, becoming strong and gusty in coastal counties. Highest temperatures generally of 1 to 4 degrees, however less cold in southwestern counties with highs of 5 to 8 degrees.

Friday night: A wet, windy night with rain turning to snow over the north, east and midlands, leading to some accumulations. Cold night for many, with lowest temperatures of -1 to +2 degrees however much of Munster and southern Connacht will be less cold with lows of 4 to 7 degrees. Fresh to strong and gusty southeast winds.

Saturday: Windy with outbreaks of rain, possibly continuing to fall as sleet and snow in Ulster and north Leinster for a time. Southeast winds will be fresh to strong and gusty. Remaining cold across the north, east and midlands with highest afternoon temperatures of 1 to 5 degrees, a few degrees milder elsewhere. Windy overnight with further falls of rain, heavy in places, possibly turning wintry in parts of the north and east. Lowest temperatures of 0 to 4 degrees, with milder conditions persisting in the southwest.

Current indications suggest Sunday will remain unsettled with breezy conditions and further rainfall. Some uncertainty regarding temperatures, with a possibility of colder and wintry conditions persisting in eastern areas.

Well that's another turn around again... what is the heck is happening with the weather, cold till Sunday now and the Thursday event looks to have more potential again besides the ECM 6Z posted by Villian having a downgrade on snow potential... although it did upgrade the cold.

Do MÉT know something we do not? :pac:

MJohnston

Don't get your hopes up too high, but the ECM 06Z isn't a total bust for eastern snow:

Nqp15hhu

If this can flip that quickly to mild it can if to cold again.

Nqp15hhu

Villain wrote: »

Some good news and some bad news!

The good news is the ECMWF 6z model shows cold hanging in longer:


Charts for 6am Friday

00z:


06z:


However it also stops the front dropping much snow further Northeast!

00z:


06z:

I’d be quite happy for the snow to stay away in order to keep the cold air.

I have said this before these fronts are bad news.

DOCARCH

Nqp15hhu wrote: »

I have said this before these fronts are bad news.

I wouldn't disagree. Sh1te from the east is better than sh1te from the west!