Forecasts for Cold Snaps/Spells and Snowy Weather only.

darkman2

Hi, just a heads up.....


Snow showers are possible even to low levels later Monday and Monday night. High ground is certain to see snow at this stage. Whilst snow is marginal for sea level - in heavy prolonged showers it is a distinct possiblity. Top temperatures on Monday will range 3 - 5C (dropping sharply in showers). Hail/sleet seems likely for most.

Also we have to watch the development of a shortwave which could bring prolonged sleet or snow to Northern parts of the country early Tuesday morning. This is only a 48hr window. It will become milder again later Tuesday.

Just something to keep an eye on:)

http://www.wetterzentrale.de/pics/Rtavn603.png

Takeshi_Kovacs

I'd say there could be a layer of snow on the mountains down here tomorrow as, it is hail stoning down there at the moment, although the ground and air is too warm for it too linger, it might stay on higher ground. Pressure stable at 1000 mb

Snowbie

Use this thread to post on forecasts from any Met Organisation on the possibility of snow from more than one day out and beyond.

Post on snow events that are presently happening or are certain to happen in this country within 24hr peroid [thread=2055023550]here[/thread]

This is to seperate a forecast for snow and an imminent type snow event.

Snowbie

Also the second week in January looks set to be cold.

Scubadevils

I am out of the country that week so the likelyhood is that there will be a full on snow storm :mad:

darkman2

Snowbie wrote:

Also the second week in January looks set to be cold.

Given the current setup I would not stick my neck out beyond a week Snowbie tbh. Northern Latitude blocking looks increasingly likely though I think it will be after mid - January. The stratosphere is warming but has not warmed enough yet to allow the PV shift from GL. Therefore its really only transitional Northerlies atm to look forward to. Beyond this I really dont have a clue.

Snowbie

Darkman2 wrote:

Given the current setup I would not stick my neck out beyond a week Snowbie tbh.

I dont usually.But i have a hunch that we will have our northern block maybe closer than mid month playin the part.Its a similar trend i have witnessed before.I will stick my neck out a little bit further than a week only this once.I have been saying this a number of times since early Dec.I go by trends and not FI and we are trending towards a chillier Jan for a good few years wheather we get snow or not but tis on course to be a lot colder 2nd week on.

darkman2

Snowbie wrote:

I dont usually.But i have a hunch that we will have our northern block maybe closer than mid month playin the part.Its a similar trend i have witnessed before.I will stick my neck out a little bit further than a week only this once.I have been saying this a number of times since early Dec.I go by trends and not FI and we are trending towards a chillier Jan for a good few years wheather we get snow or not but tis on course to be a lot colder 2nd week on.

We will see but tbh it does not look good at all at the moment. Zonal pattern to continue indefinatley for me.

Snowbie

Aye,if it doesnt come off,well there goes my trends and i definitely wont believe anything after 3 days.

Well most winters we have zonal paterns anyway,ok this one being very persistent but nonetheless the jet will give eventually and pressure will build.In two weeks we could be influencing a scandi high(no real cold air pooling over russia atm)but we need it to retro west and a Northerly to set in.Changes do take place over a short while,i wouldnt concentrate too much on FI to see an outcome,it makes for good reading but very inaccurate.

darkman2

Next weekend looks like it will be very cold indeed with temperatures struggling and the possibility of Wintry showers so not all bad news.

Trogdor

Great metcheck forecast for the 19th to the 23rd, blizzard conditions, if your reading this thought it;s probably changed already. It's sad but i've taken a screenshot and saved it as it's the best forecast for cold and snowy weather i've seen all winter
http://www.metcheck.com/V40/UK/FREE/14days.asp?zipcode=Dublin
Edit: here's the screenshot, sorry about the format i'm using a mac atm
http://www.brayweather.com/snow_forecast.pdf

Villain

Sweet Jesus trogdor thats some forecast, especially for the 21st with 17mm of Snow! Mind you its giving rain for Carlow!

Now we both now it will never happen but worth a look. It sure does look like it will get cold anyway.

Snowbie

For the last few days its has given snow to Dublin from 8 -14 days out.Its always nice to see and even better if it was pulled off.

Trogdor

Just had a closer look at it and it that colder zonality? because that's what it looks like with the wind directions

ninebeanrows

To be honest, any hope for snow for Ireland in the next 3 weeks is very small..

Were seeing Depression after Depression tracking from the Atlantic and the pattern is pretty much locked for the foreseable future.

Granted at times when the depressions push throw, colder air will be entrapped and pushed across Ireland.

So for short periods of time some wintry showers are possible in some areas.

Maybe a few sleety showers during Wednesday in the west and then perhaps some more widepread hail/sleety showers the following Sunday, but that's a long way off.

Gonzo

im with weathercheck on this one, but if that metcheck forecast comes off i'll eat me hat lol

SpitfireIV

Metcheck are sticking to there guns with this one, they are still showing 6 days of snow from Jan 19th for Dublin anyway, and have been showing that since Sunday, usually it'd be changed by now. I know its a long way off.....but still looks cool!

Isn't that met check forecast just derived from the fantasy island GFS-in otherwords its worthless...

Croppy_boy anything beyond 7 days is FI-fantasy island forecasting in our current mobile set up.

Also trogdor,theres no such thing as cold zonality-thats just an illusion or should I say a delusion dreamed up by some cold weather fans to delude themselves that the Atlantic can bring snow-it cant on its own.
It needs a northerly influence or to come up against a northerly or an Easterly from a suffeciently cold source.
The jet moving south on its own is not enough without the other influences,the Atlantic is just too warm.

Don't be taken in by the nonsensical "cold zonality" term.

Gonzo

metcheck starting to dumb down this snow forecast already for Dublin, they only have a bit of snow forecasted now. The cold spell if it happens will prolly amount to no more than one cold afternoon with a few wintry showers

Snowbie

Cold zonality is defo a new term out there.Who made it up?
What does it mean? Is it legal?
Does it refer to Rpm-Returning polar maritime air?
Does it refer to Pm-Polar maritime air?
Is it LPs on the northern side of the jet stream?

Is these terms gone and replaced by the new cold zonality if it is the same thing?

I have noticed this been used a lot on a few weather forums.

Anyone.

It's a made up term snowbie that has proliferated weather fora lately in a desperate search for snow.
It has to my eyes no basis in fact.

Meanwhile what do the GFS FI generated met check forecasts day for mid month Dublin now? Mild rain I'd say given this mornings GFS?

Don't tell me some on here have resorted to looking on them as a last resort now?

Snowbie

Metcheck are still goin for blizzards for next week Tristrame.:D
and have been doin so all this week.

Don't tell me some on here have resorted to looking on them as a last resort now

Straw clutching in hope i suppose,cant really blame them for this dyer winter in fairness.First bit of real cold comes along this forum will overload and Boards will crash.:p

darkman2

http://www.wetterzentrale.de/pics/MT8_Dublin_ens.png



VERY interesting ensembles at long last;)

Gonzo

and wot do those ensembles mean?

Snowbie

Gonzo there has been a hint in FI for the last week that a spell of cold weather will engulf this isle of ours.Now it has been persistent and only relented yesterday to back to mild wet and windy sort of stuff but changed again today. What those ensembles are telling us that for a 3 or 4 day peroid from the 19th Jan -5 850mb temps will be over the Dublin area=3c or 4c daytime air temps with the possibility of ahem!! if the conditions/ingredients are right that is.

Its a cold airmass tryin to work its way in but is still a week away and as always subject to change.

Supercell

-5°C ensembles and people are getting excited? , jaysus modern winter syndrom and lower expectations at work.

WC ain't posted anything, that should be enough of an indication as to how excited he is about it and he......

Maybe artictree,myself and a few others might see something out of that but for most it will be just rain showers if anything.

If the sneachta reaches here , I'll be snap happy and will post loads of pics

Snowbie

Whos gettin excited.Still out in FI but why not discuss it.

If its a Ntly event then its lucky any one in the east will see anything rain or the other stuff.If it just got cold it would do me fine and clear this mild muck away for awhile.

-5c ensembles are not the worst anyway.

darkman2

The average is -5. Most runs go below that to -6 or -7. Long way out but wintry weather looks a distinct possibility


http://www2.wetter3.de/Animation_18_UTC/168_30.gif

darkman2

Increasing agreement for quite a potent cold snap with the risk of snow next weekend.

http://85.214.49.20/wz/pics/MT8_Dublin_ens.png


Several models are now better for this then the 12z GFS including the UKMO.

Snowbie

Very interesting DM,just hope that run is the same on wedensday before the ramp can start.

Edit:Just seen the rest of the models and there is a bit of agreement going on for a cold spell next weekend.This is a first for a long time and first this winter.

darkman2

LOL!!!!!!!!

Real height rises over GL in the reliable timeframe:

http://www.wetterzentrale.de/pics/Rtavn1561.png

Trogdor

darkman2 wrote:

LOL!!!!!!!!

Real height rises over GL in the reliable timeframe:

http://www.wetterzentrale.de/pics/Rtavn1561.png

which leads to this;)
http://85.214.49.20/wz/pics/Rtavn1921.png
I've been optimistic so far this winter thinking that we'd get something good. I know the only reliable thing at the moment is the northerly this weekend which could still change i suppose:p but i think what it leads on to could be very interesting indeed

Snowbie

Ok lets hope the models upgrade further and keep up with height rises.A bit away from certainty atm but the best output we have seen so far.
Tuesday/wedensday cant come quick enough for it to be a defo.

Edit: DM that HP seems to want to park over us than over GL in the 18z.Still on this run to give a northerly but not artic influence yet.Needs positioning in Greenland to give us the artic blast.
0z should be interesting.

arctictree

Wow - look at the chart for Wed 24th:

http://www.wetterzentrale.de/pics/Rtavn2161.html

A strong easterly at the end of Jan?!!

How accurate are these anyway in your experience?

A

SpitfireIV

arctictree wrote:

Wow - look at the chart for Wed 24th:

http://www.wetterzentrale.de/pics/Rtavn2161.html

A strong easterly at the end of Jan?!!

How accurate are these anyway in your experience?

A

That link doesnt work for me, but seen as its over a week away I wouldnt pay much attention to it, could all change.

ninebeanrows

Wahooooooooooooooooo

Salvation at last for cold and snow lovers salvation at last..

Couldnt have seen this coming from around the tightest of bends last week but thats why the weather is so god damn good. You just dont know what ya gonna get!

This 12z is by a some way the best output of this winter, no doubt the usual cautions must be beared but the models have been homing in on this synoptic for some time but it is just getting better and better with each run.

Cold northerly next weekend turning easterly towards the New Week - fanbloodytastic:D

time for a few good ole

darkman2

Right this deserves its own thread. Ive just seen some of the best charts in years. Will post on this etraordinary upcoming cold spell later;)

Gonzo

about time we all deserve a decent dollop of snow here, we are so overdue an 80s style whiteout, I know it prolly wont happen but it wud be so cool... 6 inchs plus and the news reports 'do not venture outside unless you really have to' wud be a gud start I think:) I can only dream but maybe just maybe we get lucky this time around!

ninebeanrows

I wouldn't say the best in years Darkman i've seen better charts last year and the year before - last year they didnt materialise but the year before they do.. You need really exceptional charts to bring a good snow around here and a load of luck -- we have near exceptional charts at +160hrs and we dont know what our luck is yet...

Long time to go - charts are extremely good but not amazing at this stage:)

Takeshi_Kovacs

I dunno, i'll believe in the snow when i see it lying out side my front window, until then, it is all speculation..
though with the rain that fell today, you would have some serious amount of snow if it had been a lot colder. But what are the odds that if we do get a cold blast, that we will get dry weather with it?

lucernarian

I'm going to deliver a dose of pessimism now: this "irrational exuberance" will leave us all depressed. Look at it this way, we are depending on some supercomputers to basically predict the future. We will get cold weather and we will probably see snow within the next two weeks, but those in the pale should not get excited.

I remember at one stage last year that the ECMWF had a roaring NEely for us at 120 hours out but the next run collapsed the whole trend like a house of cards. The greenland high that we did have, delivered primarily to Donegal, and not much by historical precedent.

From those charts, I can't see how Donegal/north coast of Ireland could fail to get snow of some description from Sunday morning onwards but precipition and its path is a biatch to predict as we all (should) know. It's like pinning the tail on the ass, blinfolded. I'm particularly concerned by the positioning of the Atlantic High, and I feel its position is treacherous. We are very close to dry, cold days appearing on the charts. This particular coin is still in the air.

I have my fingers crossed, but until this coming Thursday arrives, I am reading these as a probable lack of data from the Atlantic Ocean and refuse to look at them as anything but fantastical tripe.

Here we go again!:)

darkman2

Should say snow showers are expected on Wednesday especially in the west and north.

Supercell

The 12Z ensembles are just bloody brilliant , every run seems to be getting colder which is a fantastic trend, and also looks like there will be precipitation around, especially on Monday which looks like being the peak cold day right now.

Am very very happy to see at least the possibility of snow finally and in January, in recent years we've been seeing charts like this in blooming March which has too powerful sun to allow a proper cold spell.

Fingers and toes crossed that the trend continues and doesn't melt away at 72 hours!

Snowbie

To_be_confirmed wrote:

I'm going to deliver a dose of pessimism now: this "irrational exuberance" will leave us all depressed. Look at it this way, we are depending on some supercomputers to basically predict the future. We will get cold weather and we will probably see snow within the next two weeks, but those in the pale should not get excited.

I remember at one stage last year that the ECMWF had a roaring NEely for us at 120 hours out but the next run collapsed the whole trend like a house of cards. The greenland high that we did have, delivered primarily to Donegal, and not much by historical precedent.

From those charts, I can't see how Donegal/north coast of Ireland could fail to get snow of some description from Sunday morning onwards but precipition and its path is a biatch to predict as we all (should) know. It's like pinning the tail on the ass, blinfolded. I'm particularly concerned by the positioning of the Atlantic High, and I feel its position is treacherous. We are very close to dry, cold days appearing on the charts. This particular coin is still in the air.

I have my fingers crossed, but until this coming Thursday arrives, I am reading these as a probable lack of data from the Atlantic Ocean and refuse to look at them as anything but fantastical tripe.

Here we go again!:)

Good post TBC,
Everybody take note of this it is to the point and it says it all.
Im not knocking our overdue cold,christ knows i want it too but we have to be honest with the ensembles of which the HP is of the utmost significance.If on a track towards GL we need it to go.If over us blah.

Ah exciting times ahead over the next few days.:)

Villain

Umm I go away for a few days and come back to these charts! It does seem awful far out to be getting excited about though, surely the atlantic will kick this cold snap back before we see any white stuff? Or perhaps the I'm just being negative for once hoping it will prove me wrong

fatherdougalmag

Is there not a bit more confidence behind this snap seeing that multiple models are showing the same coldness?

arctictree

Hmmm - charts on wetterzentrale seem to be changing quite a lot.

Monday still looks like the coldest day with not much change for Tue/Wed although the strong easterly seems to replaced by a north easterly.

I'd say we'll know for sure on Wednesday this week.

A

Snowbie

Use this thread to post on forecasts from any Met Organisation on the possibility of snow from more than one day out and beyond.Use model detail(GEFS,ECM etc) if and when you can to explain the posibilities.

Post on snow events that are presently happening or are certain to happen in this country within 24hr peroid [thread=2055023550]here[/thread]

This is to seperate a forecast for snow and an imminent type snow event.

darkman2

May aswell start with the ensemble chart on this thread:




Ive decided not to post charts from the models for the time being until we get over the more uncertain period and also so as not too build up too much expectation. Until then check out the ensemble chart ive just posted. As you can see really good agreement for a marked drop in temperature from the 20th. Where the average starts to rise is well into FI and should not be taken much notice of atm. Clear indication there of a very cold period of weather from this weekend. Indeed by the 22nd temperatures will be hardly getting above freezing on that chart. After that it could go anywhere from an Easterly to a Southwesterly. Fingers crossed for the former:D

Snowbie

Continue the discussion here

http://www.boards.ie/vbulletin/showthread.php?t=2055041562

Snowbie

Right,a good start may it continue.Bit of BB trouble atm whats the 18z doing with our High pressure