Cold Spell Discussion (18/12/09) (Cold, Ice and Snow now arriving)

maquiladora

Orange and Yellow Meteoalarm warnings out for tomorrow :

http://www.meteoalarm.eu/countryIE.asp?areaname=&AT=&area=&lang=EN&Country=IE&ShowDate=tomorrow

Connacht and Ulster predicted to get up to 2 inches, all other areas up to 1 inch.

Expect a proper weather warning from Met Eireann in the morning.

maquiladora

"Snow will be widespread across Wales, southern England, and Ireland on Saturday night. From 3-5 centimeters may fall in a matter of hours as the front passes."

http://www.accuweather.com/ukie/news-story.asp?partner=accuweather&article=0

WolfeIRE

Still dont know why RTE News (website) have deleted all references to their snow story.

www.rte.ie/news

Slippin Jimmy

WolfeIRE wrote: »

Still dont know why RTE News (website) have deleted all references to their snow story.

www.rte.ie/news

They probably don't know themselves. Interesting posts from the above posters. I wonder will we see snow on Sat so......

maquiladora

WolfeIRE wrote: »

Still dont know why RTE News (website) have deleted all references to their snow story.

www.rte.ie/news

Maybe because in their TV report at least they make a blunder by saying that the cold spell wont contine into next week while Met Eireann says it will until at least the middle of the week.

philstar

a white xmas maybe?? worth going to the bookies??

Tactical

Time to catch a few Z's for me.

Busy day tomorrow and ever hopeful that we'll all see a few flakes over the weekend.

WolfeIRE

Nite tactical.

It is very unusual for RTE to take down a story like that - especially one that was the most read on their website all day. It's been down for about 2 hrs. I have never seen such uncertainty regarding the weather for a 24 hr period. Nobody really knows what way it will turn out.

maquiladora

philstar wrote: »

a white xmas maybe?? worth going to the bookies??

Too far out to call but at the moment it looks like it might start to get milder on or around xmas day.

philstar

WolfeIRE wrote: »

It is very unusual for RTE to take down a story like that - especially one that was the most read on their website all day. It's been down for about 2 hrs. I have never seen such uncertainty regarding the weather for a 24 hr period. Nobody really knows what way it will turn out.

RTE playing it safe, me thinks:cool:

K-9

maquiladora wrote: »

"Snow will be widespread across Wales, southern England, and Ireland on Saturday night. From 3-5 centimeters may fall in a matter of hours as the front passes."

http://www.accuweather.com/ukie/news-story.asp?partner=accuweather&article=0

My Forecastfox is giving up to an inch tomorrow, same Sunday.

WolfeIRE

philstar wrote: »

RTE playing it safe, me thinks:cool:

It was one of their top stories all day but now doesnt feature out of more than two dozen stories on their website. Someone said now it's a case of looking at the radars and making 1 hr predictions. Met Eireann's prediction of heavy wintry showers along the North and West coasts tonight has also failed to materialise.

Hence they have taken the unusual step of updating their forecast on met.ie at 11.45pm (looks like somewhat of a downgrade from the 4.20pm update)

18 December 2009 23:45

Today Very cold tonight with clear spells and well scattered wintry showers. Minimum temperatures zero to minus five degrees leading to icy stretches.


Tomorrow

Sunny spells at first on Saturday then becoming mainly cloudy with outbreaks of rain and early afternoon temperatures of 2 to 6 degrees. Temperatures will fall quickly below zero by dusk with sleet or snow following and icy stretches.

Outlook

It will remain cold over the weekend and well into next week, with widespread frosty nights, icy stretches and freezing fog too. Further wintry showers, but longer drier spells too. Starting off extremely cold on Sunday morning, with frost slowly clearing. Some lying snow from overnight is likely too, mainly across parts of Ulster, Connacht, north Leinster and west Munster, in particular over the higher ground here. The day will be cold, bright and breezy, with sunny spells and scattered wintry showers, mainly affecting western and northern counties. Feeling very raw, with highest temperatures just 1 to 4 degrees, and moderate to fresh northwest breezes. Very cold and frosty overnight with icy roads, with temperatures dipping well below zero across many areas. Mostly dry under clear skies, however a few wintry showers will occur along northern and western coasts. The cold snap will continue into Monday and Tuesday with temperatures struggling to reach anymore than 2 or 3 degrees at most, with just light variable breezes. Wintry showers of sleet and snow will occur more widely, with some sunny spells developing at times too. Further severe frosts as well as freezing fog and icy conditions developing countrywide soon after dark.

darkman2

This is the latest precipitation and type forcast for tomorrow evening. Like I say a 3 hour snow window or there abouts. It should be cleared by 10pm.
Isolated snow showers following after the main event so to speak.

fintonie

the problem is its going to get to cold for snow and it will,

its just a case of the temp dropping to a snowage,

if this happens there will be buckets full

nacho libre

owenc wrote: »

so were getting no snow tomorrow night!!!!!!!

ah yeah we will. i was just being a pessimist earlier. it's just that if the precipitation starts off as rain the accumulations won't be as good as they could be at lower levels if it was snow throughout.

WolfeIRE

darkman2 wrote: »

This is the latest precipitation and type forcast for tomorrow evening. Like I say a 3 hour snow window or there abouts. It should be cleared by 10pm.
Isolated snow showers following after the main event so to speak.

It is safe to say that there will be snowcover just about everywhere in Ireland this time tomorrow.

Dark do you have any guesses on where there will most likely be most snow cover?(other than traditional haunts - sally gap etc)

ninebeanrows

It will be a now cast situation, you could get intense heavy snowfall for 2-3 hours and have 5 inches lying or just have about 10 minutes of snow at the back of the front falling on soaking ground.

It will depend on the dynamics of the front.

ninebeanrows

WolfeIRE wrote: »

It is safe to say that there will be snowcover just about everywhere in Ireland this time tomorrow.

Dark do you have any guesses on where there will most likely be most snow cover?(other than traditional haunts - sally gap etc)

I believe the front will probably die on its western edge as it pushes south, that is my experience of cold front passages south on northerlies, so the further north and east IMO the better but this could easily change.

naughto

can it get to cold to snow???

darkman2

WolfeIRE wrote: »

It is safe to say that there will be snowcover just about everywhere in Ireland this time tomorrow.

Dark do you have any guesses on where there will most likely be most snow cover?(other than traditional haunts - sally gap etc)

It's impossible to say - too many variables. Temperatures may not be condusive to freezing the rain water in time tomorrow night for pavement settling at sea level. On the grass, dust bins, palm trees etc it is very likely to be white by 10pm. How much is impossible to say. Bare in mind there is a margin of error in all these forcasts. There could well be more or less precipitation then forcast. I will go for 2 - 3cm max at sea level mostly on grassy surfaces. 6 - 10cm depending on elevation. An Ice day to come on Sunday for many regardless.

fintonie

naughto wrote: »

can it get to cold to snow???

yes it needs to be bout 1 degree 2 at the most, you can have forced snow if that happens most times its a big fall

darkman2

Weathercheck wrote: »

I believe the front will probably die on its western edge as it pushes south, that is my experience of cold front passages south on northerlies, so the further north and east IMO the better but this could easily change.

We are at the crux of where the occlusion, warm front and cold front meet in the East - so we should get the most expansive area of precipitation in the country. I do wonder whether it will only be a useless snowy back edge. Thankfully the cold air we need for snow is slightly ahead of the cold front so a decent shot. Colder air coming like a steam train behind.

Sierra Oscar

We had no snow here tonight . . . tomorrow evening should be interesting.

darkman2

darkman2 wrote: »

We are at the crux of where the occlusion, warm front and cold front meet in the East - so we should get the most expansive area of precipitation in the country. I do wonder whether it will only be a useless snowy back edge. Thankfully the cold air we need for snow is slightly ahead of the cold front so a decent shot. Colder air coming like a steam train behind.

LOL I dont know what you mean by the above, but I see a smilie, so it must be good

darkman2

naughto wrote: »

can it get to cold to snow???

No.

bassy

so after all our exspectations,are we only gonna get a wee covering of snow?.

WolfeIRE

darkman2 wrote: »

We are at the crux of where the occlusion, warm front and cold front meet in the East - so we should get the most expansive area of precipitation in the country. I do wonder whether it will only be a useless snowy back edge. Thankfully the cold air we need for snow is slightly ahead of the cold front so a decent shot. Colder air coming like a steam train behind.

Am i right in saying that this is not a very common scenario for Ireland i.e. to have a cold front pushing down from the artic into an already cold airmass at this time of year?

Is that why there is so much uncertainty, because weather forecasting is based a lot on previous experience 9which we have had little in recent years) as well as GFS/UKMO type assistance?

nacho libre

WolfeIRE wrote: »

yes, but galway/clare tend to fair well from a NW flow, as well as inland to roscommon, leitrim, and parts of north tipp, offaly.

That set set up looks like staying in place until midweek with winds turning even more westerly by wed.

but isn't it likely with it getting winder and given the wind direction the showers will turn sleety than being purely of snow by that stage?

i have a feeling staurday night, as the front is clearing, is our best chance for widespread and fairly heavy snow across much of the country. after that it wouldn't surprise me if most of the snow is confined to north connacht and ulster after that with the odd shower making it further south and east. then perhaps by late next week we could get more widespread frontal snow if we become the battle ground between the cold air and warmer atlantic air.

darkman2

Jake1 wrote: »

LOL I dont know what you mean by the above, but I see a smilie, so it must be good

Fax synoptic chart for tomorrow 18:00. Hmmm my analysis is that the system is not as developed as was originally thought. On the upside the warm sector won't be as big. On the downside this could weaken precipitation potential. The warm sector is located between the two shadow fronts ahead and the cold front behind. A very interesting chart though. It could start as sleet which would be preferable to rain.

nacho libre

Deep Easterly wrote: »

Looked particularly bad for the NW on the Atlantic charts she showed.

"bad" ? i suppose that depends on your perception:pac: