Boards.ie uses cookies. By continuing to browse this site you are agreeing to our use of cookies. Click here to find out more x
Post Reply  
 
 
Thread Tools Search this Thread
16-01-2018, 06:26   #1
Kermit.de.frog
Registered User
 
Kermit.de.frog's Avatar
 
Join Date: Apr 2014
Posts: 8,852
Snow/Ice Warning for Ulster : PM 17th/AM 18th, Jan 2018

The main models continue to weaken storm potential for Wednesday evening and in to Thursday and increase snow potential as the storm system looks to move further south.

With the reduction in the wind threat comes an increase in the snow risk.

The storm thread is here

https://www.boards.ie/vbulletin/show...p?t=2057829980

At the moment all of Ulster and possibly northern counties of Leinster are in line for persistent and sometimes heavy snowfall.

This may yet change further. The ECM, for example, has snow potential even further south taking in more of Leinster and northern Connaught.

Given we are within the 48 hour timeframe big changes shouldn't be expected but still some uncertainty there.

For now the focus is Ulster - including Cavan, Monaghan and Donegal.

This could be disruptive for the province.

I'd go with 5 - 10 cm - locally more and on high ground. Looks a decent enough event.

Last edited by Kermit.de.frog; 17-01-2018 at 02:59.
Kermit.de.frog is offline  
Advertisement
16-01-2018, 07:39   #2
Wine Goddess
Registered User
 
Join Date: Dec 2010
Posts: 327
Kermit I love your enthusiasm for snow! And your knowledge....
Wine Goddess is offline  
16-01-2018, 08:02   #3
piplip87
Registered User
 
piplip87's Avatar
 
Join Date: Apr 2016
Posts: 579
Great in Virginia Cavan and often the weather we get is what is forecast for North Leinster. Hopefully get a nice pasting from this
piplip87 is offline  
Thanks from:
16-01-2018, 17:10   #4
M.T. Cranium
Registered User
 
Join Date: Apr 2007
Posts: 10,089
Not downgrading the wind potential for south and central counties but this snow threat is real if the track ends up inland, it simply won't warm up much north of the track of the low and could stay mostly snow in Ulster and high ground in Connacht before, during and after passage of this low.

If it intensifies and follows this track, very tight gradients would develop, and even more snow potential would exist (5-10 cm sounds about right to me also).
M.T. Cranium is offline  
16-01-2018, 19:21   #5
mirrorwall14
Registered User
 
Join Date: Jul 2014
Posts: 4,677
Quote:
Originally Posted by M.T. Cranium View Post
Not downgrading the wind potential for south and central counties but this snow threat is real if the track ends up inland, it simply won't warm up much north of the track of the low and could stay mostly snow in Ulster and high ground in Connacht before, during and after passage of this low.

If it intensifies and follows this track, very tight gradients would develop, and even more snow potential would exist (5-10 cm sounds about right to me also).
Any chance it will run south and plaster the midlands as well as the north?
mirrorwall14 is offline  
Thanks from:
Advertisement
16-01-2018, 21:45   #6
Donegal Storm
Registered User
 
Donegal Storm's Avatar
 
Join Date: Dec 2016
Posts: 1,134
Arome going for high ground in Ulster only



WRF and Arpege a bit more optimistic though again mainly higher ground



Donegal Storm is offline  
(3) thanks from:
17-01-2018, 00:06   #7
Kermit.de.frog
Registered User
 
Kermit.de.frog's Avatar
 
Join Date: Apr 2014
Posts: 8,852
Hirlam - slightly further south with the track.



Guess it will be somewhere in between.
Kermit.de.frog is offline  
17-01-2018, 00:35   #8
sdanseo
Registered User
 
Join Date: Aug 2005
Posts: 7,975
Bodes well potentially for a few more of us. HIRLAM fairly nailed today's events. Logic would suggest based of its precip frame above that any more than 50km further south on the morning runs and we could be talking disruption in a lot of Leinster come Thursday morning.

I'm a bit confused though, uppers from HIRLAM for the same frame would suggest far too warm?

sdanseo is offline  
Thanks from:
17-01-2018, 00:42   #9
pad199207
Registered User
 
Join Date: Jan 2010
Posts: 3,640
Those in Ulster and Leinster should be keeping a very close eye on this.
pad199207 is offline  
(2) thanks from:
Advertisement
17-01-2018, 01:14   #10
pauldry
Registered User
 
Join Date: Jul 2009
Posts: 3,605
Sligos right on the border for this.

Interesting ...again...this great Winter
pauldry is offline  
17-01-2018, 01:31   #11
nacho libre
Registered User
 
Join Date: Aug 2006
Posts: 12,200
Quote:
Originally Posted by sdanseo View Post
Bodes well potentially for a few more of us. HIRLAM fairly nailed today's events. Logic would suggest based of its precip frame above that any more than 50km further south on the morning runs and we could be talking disruption in a lot of Leinster come Thursday morning.

I'm a bit confused though, uppers from HIRLAM for the same frame would suggest far too warm?

not necessarily. you can get snow with such uppers when you have cold air in place, provided the wet bulb temperature is low enough(0.6) you sometimes can even get snow at 4c. indeed some of the greatest frontal snow events in Ireland have come about in marginal situations. i would like to think given the winter we have had, we will get one epic countrywide frontal snow event- it has to happen at some stage
nacho libre is offline  
17-01-2018, 01:35   #12
Donegal Storm
Registered User
 
Donegal Storm's Avatar
 
Join Date: Dec 2016
Posts: 1,134
Arome is generally very good for snow predictions from what I've seen in the brief time I've used it, it forecast the frontal snow events last month almost perfectly. For some reason though it didn't pick up todays event at all, it showed very few showers over the country all day (not even rain showers) and no snow accumulation at all. Must be an issue with whatever global model its getting its input conditions from for the Atlantic though still bizarre it was so far off

This is what its showing tomorrow, snow anywhere above approx 150-200m to start with and I assume the orange cross hatching is sleet



Before eventually transitioning to snow for most areas in north Ulster

Donegal Storm is offline  
Thanks from:
17-01-2018, 01:42   #13
sdanseo
Registered User
 
Join Date: Aug 2005
Posts: 7,975
Orange = hail or graupel "niege roulee" literally round snow
White = snow or sleet "niege verglacante" - literally icy rain
sdanseo is offline  
Thanks from:
17-01-2018, 03:41   #14
nacho libre
Registered User
 
Join Date: Aug 2006
Posts: 12,200
So North Mayo, parts of Sligo, Cavan could get a blizzard tomorrow night

I bet though it will end up further north if it intensifies quickly while engaging the jet stream and fionn's energy.
nacho libre is offline  
17-01-2018, 05:29   #15
Kermit.de.frog
Registered User
 
Kermit.de.frog's Avatar
 
Join Date: Apr 2014
Posts: 8,852
This thread probably needs an orange warning in my opinion. This could be a very disruptive event.

Can a mod please add the following counties to the OP?

The counties are Antrim, Armagh, Cavan, Louth, Sligo, Leitrim, Meath (North), Tyrone, Donegal, Derry, Fermanagh, Down, Monaghan, Roscommon.

Blizzard like conditions are highly likely at times.

Also high ground in Wicklow will be appalling - avoid.

Duration is 6 - 9 hours from night fall tonight.

Last edited by Kermit.de.frog; 17-01-2018 at 06:15.
Kermit.de.frog is offline  
(4) thanks from:
Post Reply

Quick Reply
Message:
Remove Text Formatting
Bold
Italic
Underline

Insert Image
Wrap [QUOTE] tags around selected text
 
Decrease Size
Increase Size
Please sign up or log in to join the discussion

Thread Tools Search this Thread
Search this Thread:

Advanced Search



Share Tweet