Winter 2017-18: Discussion

sryanbruen

The NAO taking baby steps in improving here for cold on the GFS ensembles. There is one outlier on today's update that goes down to neutral or very slight negative NAO at the end of the run. If everything goes according to what I expect, we should see negativity of the NAO being more general in about 10 days. It's ridiculous how long it has been positive.

BLIZZARD7

sryanbruen wrote: »

The NAO taking baby steps in improving here for cold on the GFS ensembles. There is one outlier on today's update that goes down to neutral or very slight negative NAO at the end of the run. If everything goes according to what I expect, we should see negativity of the NAO being more general in about 10 days. It's ridiculous how long it has been positive.

Extended GEFS have the NAO going firmly negative -



ECM ensembles too -





http://wx.graphics

George Sunsnow

Jeeze you could taboggan on some of those ensembles

sryanbruen

George Sunsnow wrote: »

Jeeze you could taboggan on some of those ensembles

I wish I could in Phoenix Park like all these young ones and their families did in January 1982.

http://www.rte.ie/archives/2016/0115/760459-the-big-snow/

sideswipe

^^^ brings back memories!! Heavy snow and a fertilizer sack:)

pistolpetes11

https://twitter.com/pppapin/status/962118691096731648

I know you can embed a tweet but can for the life of me figure how to do it , but then I figured it

Meteorite58

https://twitter.com/severeweatherEU/status/962081901082181633

NAGDEFI

Rougies wrote: »

I think a decent cold easterly in late feb / early march would absolutely destroy any notions you have of a couple of extra daylight hours and sun strength being a major factor regarding temperatures and snow accumulations.

It is a factor of course, but we're usually so marginal that the heat from a bear sh1tting in the woods (if we had bears) upstream would make the difference between rain and snow even in the deepest depths of winter.

If a potent easterly flow from a cold russia/europe happens before St. Patricks Day we'll be good.

I never recall snow lying for 2 or 3 days in Dublin in March. December, January and February ok.

Even Monday 11th of March 2013, with uppers of -16, brought snow showers which melted when the sun came out.

Donegal Storm

March 22nd 2013 all the way through to early April had lying snow close to sea level in Belfast so if it can happen there there's no reason it couldn't happen in Dublin.

I'd echo your sentiments that snow is far more welcome in early winter but prolonged snow is still perfectly possible in the coming weeks given the right conditions

NAGDEFI

Donegal Storm wrote: »

March 22nd all the way through to early April had lying snow close to sea level in Belfast so if it can happen there there's no reason it couldn't happen in Dublin.

I'd echo your sentiments that snow is far more welcome in early winter but prolonged snow is still perfectly possible in the coming weeks given the right conditions

I agree Donegal Storm. Just historically i can't remember a few days lying snow in Dublin in March. Stand to be corrected. For example, January (1982, 1987), February (1991), December (2010).

Donegal Storm

Lying snow in Dublin is rare at the best of times, even in the most extreme events we've had it's a toss up whether the immediate east coast saw lying snow. I was in Belfast the day after the blizzard in 2013 and saw plenty of crazy deep snow (even at sea level it was close to a foot deep) and was back again in early April and there were still large patches of lying snow with deep snow in the hills so its definitely still possible late in the season.

'82 and back were before my time but people speak fondly so we can only assume their memories are accurate and hope for a repeat!

nacho libre

Rougies wrote: »

I think a decent cold easterly in late feb / early march would absolutely destroy any notions you have of a couple of extra daylight hours and sun strength being a major factor regarding temperatures and snow accumulations.


If a potent easterly flow from a cold russia/europe happens before St. Patricks Day we'll be good.

Yes, if the cold outbreak that Britain experienced during late February and March 2013 had taken hold in Ireland, the talk of a stronger sun and extra day light hours would soon be forgotten on here. Britain had ice days back then and some decent accumulations of snow at times too. The Channel Islands experienced a noteworthy snow storm that year also.

Gaoth Laidir

Large Funeral wrote: »

I never recall snow lying for 2 or 3 days in Dublin in March. December, January and February ok.

Even Monday 11th of March 2013, with uppers of -16, brought snow showers which melted when the sun came out.

We've never had uppers of -16, not even Dec 2010 or Jan 1982. About -12 is as low as we can get. This was 2013.



If you have full deep snow cover then the sun has little effect on it in March. It's when you get one exposed melted patch that allows the sun to heat up the exposed ground that melting really takes off compared to December or January.

George Sunsnow

We may have had very low for Ireland uppers at times in our history when such things weren’t recorded
Regardless this mornings models are another reason not to be looking until after the strat warming has took effect
A Big greenie low at day 10 on the ECM for example isn’t a sign of immediate northern blockling
Compared to yesterday ,a complete reversal
Ergo both are probably nonsense
I’m leaning back towards wait until that strat has warmed and those stats are fed into the start data

It’s been a while anyway since FI ECM has had verified easterlies
It may have no choice soon

ZX7R

I remember reading a layman's article about sudden stratosphere warming, it said that if there was to be cold air in place in a area all ready it could speed up the effects of the warming, as the cold air would look for the path of lease resistance

sryanbruen

Large Funeral wrote: »

I never recall snow lying for 2 or 3 days in Dublin in March. December, January and February ok.

Even Monday 11th of March 2013, with uppers of -16, brought snow showers which melted when the sun came out.

See my latest post in the Irish Weather Statistics thread. I posted it there because this discussion is off topic to FI Charts.

https://www.boards.ie/vbulletin/showthread.php?p=106107384#post106107384

sryanbruen

There were short incursions of the PV splitting in February 2001 then the 27 February blizzard and early March cold snap occurred following it.



I'd like to thank this guy for spotting it for me.

https://twitter.com/wanstead_meteo/status/962269116496269312

https://www.boards.ie/vbulletin/showpost.php?p=50609871&postcount=1

Gaoth Laidir

George Sunsnow wrote: »

We may have had very low for Ireland uppers at times in our history when such things weren’t recorded

Unlikely. The reanalyses go back over 100 years and don't show such low figures.

sryanbruen

Deepest snowfall in Paris since 1987.

https://twitter.com/bbcweather/status/962276224843304960

George Sunsnow

Oh I don’t know about that I was thinking during the maunder min when I wrote that
I wasn’t restricting the timeframe
So let’s say prob 40

George Sunsnow

A balmy sunny 10.7c here near Arklow now
11.8 mm rain since midnight

NAGDEFI

Gaoth Laidir wrote: »

We've never had uppers of -16, not even Dec 2010 or Jan 1982. About -12 is as low as we can get. This was 2013.

-15 out beyond the west coast during January 1987 cold spell. Apologies for difficulty in seeing small font on isotherm! New poster seem unable to post images yet.

http://www.wetterzentrale.de/reanalysis.php?jaar=1987&maand=1&dag=12&uur=1200&var=2&map=1&model=noaa

sryanbruen

Another strange thing to add to the abnormal season of 2017-18.

'Exceptional mobilization' as cold wave hits Morocco, south blanketed by extremely rare snow again

https://watchers.news/2018/02/09/southern-morocco-snow-sahara/

2nd time in a week
2nd time in 50 years.....

Just to remind you of other abnormal things this season has delivered.

• Very cold uppers and some quite snowy episodes from northwesterlies for UK & Ireland
• Florida snowfall
• Paris snowfall
• Solar activity having some weird spikes (September 2017's SSN was the highest since 2015) yet close to solar minimum. This was evident with very old similarly weak solar cycles to 24.
• Persistent positive NAO throughout the season up to this point.
• PV split and SSW especially going by the fact that this is occurring in February.
• Ex-hurricane Ophelia and the bizarre scenes it caused in Britain.
• Taiwan and China snowfalls.
• Siberia reaching near record cold levels.
• Record breaking snowfall in Moscow.
• Very dull December in Europe with December 2017 being the dullest month since December 1934.
• Snow and thick rime in Lanzarote.
• Winter Storm Benji hitting Texas bringing heavy snow.

Happygosad33

As someone who has live in the North West for 62 years. Snow from a NW is not abnormal. Also I thought Ophelia hit Ireland and missed Britain.

sryanbruen

Happygosad33 wrote: »

As someone who has live in the North West for 62 years. Snow from a NW is not abnormal. Also I thought Ophelia hit Ireland and missed Britain.

You misread my post on both points. It's abnormal for the east of Ireland along with parts of England and Wales to have snow from a northwesterly. I didn't say Ophelia hit Britain. I just said it caused some bizarre scenes over there - which I showed in the Weather Pictures sub forum.

JCX BXC

That article regarding Morocco states there was 2.82m of snow recorded in some areas, that's hardly correct?

NAGDEFI

Don't know quite where to say this so might aswell here.

This is a really excellent weather forum. Contributions are excellent. Lovely atmosphere where points are debated with respect and decorum. Really informative.

Have a feeling everyday will be a school day for me here!

Happygosad33

Fair enough. Did I hear correctly that Moscow recorded it highest daily total snowfall ever recently. 8.6 Inches not sure on precise figure. I was surprised to hear it was higher.

sryanbruen

JCX BXC wrote: »

That article regarding Morocco states there was 2.82m of snow recorded in some areas, that's hardly correct?

Lol maybe, I don't know much about it. Somebody just pointed it out to me and I was amazed by it given how strange the season has already been, let alone this.

Here's another link on it.

http://www.aljazeera.com/news/2018/02/morocco-rare-snow-falls-time-winter-180207104614251.html

Happygosad33

Assume that would be high up in the atlas mountains