Winter 05/06 indications thread (part two)

lucernarian

To quote yer man (Ger Fleming I think): "Which will be on just after the 1 o'clock news" or something very like that. "Ear to the ground" is scheduled at 1310. Havent seen the farming forecast before so does it take place during "Ear to the ground" or durring the News?

P.S. I've seen the London ensembe and conpared it to the Dublin one and there seems to be a big difference in certainty between the two. I've never seen the runs in such agreement 12 days after the run was calculated. The 850 hPa temps are below zero on every run for over a week! Happy days:) London is far less certain for some reason.

Gonzo

its looks like the colder weather might come a day earlier than expected next Thursday with Friday staying very cold and then a slightly milder but still north easterly airflow remaining into the beginning of the following week drifting air from southern sweden thru denmark and across into Ireland., Im not sure will we see any snow from it at lower levels maybe just sleet (its just so early) but there shud definitely be snow on higher ground. If this was late December/January we'd be laughing. Interesting times ahead tho, I expect this forum to be alive and well all through next week:)

*edit* just checked metcheck and they have are predicting rain next thursday turing to heavy snow by nightfall in Dublin, a cold weekend then things getting milder temporarily before another cold plunge bringing more snowrisk by December 3rd with temperatures close to freezing by day.

Already this is looking better than last winter and its not even december yet.

Danno

Danno wrote:

Looks like we'll be stuck to www.met.ie/recentweather on Thursday night! I can see it now:

2100z Knock Airport -1 Snow
2200z Mullingar -3 snow
2300z Kilkenny -5 snow
0000z Rosslare +4 sleet

I doubt kilkenny will see snow on Thursday night.
Not that far south from a northerly.
I'd also expect Rosslare to hit 0 in a proper winter northerly as the air is travelling down from the land mostly(esp with a hint of northwest)

lucernarian

The ooz and 06z chart for Friday midnight is quite different than the 18z chart. The source of the cold air is cut off with the low pressure instead starting to drag air from Eastern Europe.

I am wondering if a ridge will form between the Atlantic High and the HP over Russia. If they were to merge together AFAIK this would help the chances of an easterly system forming. I would expect it to be a far-off occurrence if it did happen at all. Perhaps sometime in mid December we could see an easterly on the cards?

As for next weekend, things are still looking good. I think this event will be confined to the hills and for everywhere else, it's still on a knife edge. As the could be quite low, I would expect a lot of precipitation. But what will it be? Who knows:p

Mothman

Earthman wrote:

I doubt kilkenny will see snow on Thursday night.
Not that far south from a northerly.
I'd also expect Rosslare to hit 0 in a proper winter northerly as the air is travelling down from the land mostly(esp with a hint of northwest)

I think you left out 1 in front of the 0

I don't believe there is a chance of Rosslare recording 0C next week.

If I'm proved wrong, I'll be more than happy

I said proper winter northerly


It will get significantly lower than 10 though

It's too early for an Easterly.
Near Europe isnt nearly cold enough.
By the time that air gets here it will be what they call a mild easterly.


How many times do I have to tell ye....

Winter is late december,january and february!!

Anything before that is unlikely to deliver and anything after that would want to have an exceptional feed of cold behind it.

This "event" a week before it happened already had the "dreamers" out making it something it never was going to be and now its as expected by the realistic set changing already into something more ordinary(but cold)

They dont call those far ahead charts fantasy island for nothing.

Supercell

http://weather.noaa.gov/pub/fax/PPVP89.TIF

OMG!! , Friday looks "interesting" to say the least!!

It's a north westerly down the Irish sea though...
Good for Ulster North Leinster and Connaught but not great for Dublin and the East.
Those trough lines are heading into Wales like.
So the best North Leinster can get out of that is the remenants of what passes over land from Ulster.

Hard to say what that would be, but look west too and you'll see pressure is high on that chart-so the real hope of activity is drifting down the Irish sea and into Wales.

If I was to guess from that and it would be a poor guess this far out-I'd guess North and East Ulster should see activity and maybe louth Meath.
Dublin would be pushing it as the flow is away from there.

Impossible to tell obviously untill nearer the time and you get a better idea of the strength and size of the features that develop

Earthman

Earthman wrote:

Off ye go - post all your thoughts on whatever trend you want to highlight in advance of it happening in the winter season here.

As per the charter-no new threads on potential severe weather unless it's merited-otherwise the new threads will be merged into this one which is a waste of time and effort for the mod and the poster

This thread will remain a sticky and is likely to be replaced by a part 2 thread , a part 3 thread etc depending on how long or unwieldy it gets.

I'd rather not see each part longer than 3 or 4 pages-so thats the rule of thumb.
For continuity purposes, if you as a poster can remember that guideline,then at page 3 or 4, you can start a new one with the same title and I will lock & unsticky this one and sticky the new one.

As per above-I've created a new thread and started it this time with a few posts from the old one.
I've also merged Danno's snow watch thread into this one as it was turning into a similar discussion ie an indications thread.
Someone can start a thread to monitor what this predicted cold spell is doing when it arrives either thursday/Friday.
I think that would be better and neater and then all the discussion can go there untill it goes back to talk of future weather.

Danno

The Eagle was *interesting* at 1310z.

Sounded very good until he put up the Chart for Friday - 3-8c

Bah!

3-8c

Well it is november For fcucks sake

like I said Winter is December, january and february ie those are the months that synoptics like this would deliver though still only as the eagle said for the north and west.

Remember that picture of the Shannon freezing-that was under an Easterly influence and I'll bet it wasn't in Novemebr or early December either

Danno

Too true Earthman, but I have fond memories of being snowed outta of it in late November... 1991 me thinks...

Danno

Metcheck have upped the snow chance to 100% for me for 0000z on Friday, also the 7-day outlook has a nice 2.5cm of snowfall...

Now who do I go with - Mr J Eagle or Mr A Bond?

what do ya mean by snowed out of it though?
How long did it last and how deep? anything less than 3 inches is not snowed out of it in my opinion especially when its slushy and gone by the end of the day or in a day or two.
It's Just as rare an occurance as a hot day in November tbh-its not that it doesnt happen,its just that its unusual.
The other thing is the obvious, the synoptics that gave you your november snow would deliver something a lot better if they were in January.

You are actually in a better location than most for snow-distance from the sea wise.

From speaking to farmers on the high ground near here, they had to haul milk by tractor regularally most winters in the late 70's up untill the early 90's.
Not just once in the winter but several times.
I'm only 2 miles from the sea here and I can remember trudging through snow more than a few times every winter in the 80's.
Schools in Arklow would be closed.
By trudging,I'm talking 6 inches or more.
This has happened here iirc once in the last 15 years.
The 2 or 3 inches that some experienced(gone by night fall for a lot) last february was a miserable efort in comparison.

It would be hard to argue against the fact that something had happened to create that lack of winter weather.

Lets hope the UKMO are right about this season(though frozen outdoor pipes would be a calamity on a farm)

Danno

True, I remember some of those 80s winters myself, Jan 87 sticks out, 2 to 3 feet of snow for just under two weeks.

January 82 was better
Though I remember a drift covering the car in front of the house here in january 87
Indeed the pillars as you enter the front drive were covered over, thats 4 or 5 feet.

Well if we dont get scenes like that again this year, we never will(well maybe)

Time to go back on topic methinks.

Supercell

I'd say Danno has a better chance than most of seeing the white stuff here, he is well inland and reasonably far north.

Alas on the east coast, even if it does snow would be suprised to see anything sticking for more than about 6 hours, that said it does bode well for the winter ahead that we are even thinking about snow this early in the year.

I don't remember seeing so many morning frosts in a row for many many years here - the frost in my sheltered back garden only melted around midday!

Its great and exciting to see it develop though

Gonzo

another really severe night frost here, its stilll really white in most of the garden, whatever about snow this winter already this winter has seen more frost in my area than the entire winter season of last year and its still over a week to December! I think over the past 8 nights about 6 of them have been cold and frosty.

Thats to be expected though with a big area of high pressure over the country at this time of the year and long nights.

It's not indicative of extra cold weather, its just what you get normally with a high at this time of the year.
It's also what you generally get with clear skies at this time of the year without high pressure unless the air is fed from deep south or south west.

You can have a south westerly that gives snow if its not a true south westerly ie, its blowing in from the south west but its source is an artic northerly blowing down from greenland through the atlantic before veering NW towards Ireland.

Thats what gave cork and Kerry a pretty good Xmas snow fall a few years ago.

Danno

Yeah, and most of the rest of Ireland god muck...

Not often Kerry steals the snow show!

Wibbler

It's gone very quiet on this thread (well in comparison to similar threads on other weather forums. Is everyone here keeping their powder dry?

nah

It's just that the posters here get active when theres a hint of more severe weather.

Speaking of which, the cold air is holding on by the skin of its teeth here
5.6c is the max so far today.


It's a sign

Seriously though it's an indication that if theres an Easterly later in the winter and a cold vs mild battle with a system heading up from the south or west, then, it could be a different world in the East

Lots of winter yet to come to see if thats served up.

Wibbler

Yeah, I'm missing the cold ramping, I guess.

There's a huge amount of activity on the net-weather autum/winter discussion thread, and although this forum has a much smaller audience I was kind of expecting more discussion about where this winter might be headed, from the perspective of Ireland.

I discovered this forum last year, in and around the February cold snap and it was a joy to read with lots of analysis and ramping in the mix.

Danno

I guess Irish Weather Fans have not embraced the internet on the same scale as their English counterparts...

...but Weathercheck makes up for the most of them!

Max temps here today was 4.5c. It was a big dissapointment this morning to see 1.5c on the thermometer and rain falling, damn that upper mild air!

Wibbler

Anyone care to shatter the peace with some further analysis of the indications for winter, or has it all been done to death for now?

Also, as a noobie to winter weather watching I'd be interested in being pointed in the direction of some basic guides to the subject. Hope that's not OT.

Supercell

Wibbler wrote:

Anyone care to shatter the peace with some further analysis of the indications for winter, or has it all been done to death for now?

Also, as a noobie to winter weather watching I'd be interested in being pointed in the direction of some basic guides to the subject. Hope that's not OT.

This winter predictions are the realm of the hobbyiests, beyond 3-5 days current science becomes more forest than tree .

Stats wise ..its over due a cold winter..and thats about as good a prediction anyone can give....

Mothman

Wibbler wrote:

Anyone care to shatter the peace with some further analysis of the indications for winter, or has it all been done to death for now?

Also, as a noobie to winter weather watching I'd be interested in being pointed in the direction of some basic guides to the subject. Hope that's not OT.

Net-weather have a good section here

A diagram of the North Atlantic Oscillation has just been added, and is partly what the UKMO have used to prompt the forecast of a cooler winter.

Anyway the coolish (or at least lack of mild) weather looks like continuing for first half of Dec once we get through the next couple days.

Mothman

Mothman wrote:

Anyway the coolish (or at least lack of mild) weather looks like continuing for first half of Dec once we get through the next couple days.

Yeah,I've been noticing all the chatter elsewhere about that.

What I find interesting about the coolness is how much easier it will be for an actual cold snap to take effect quicker when we are already well cooled down.

Scubadevils

Was without internet access for a couple of weeks so missed any excitement around the snow (or near snow) last week - had to rely on the weather forecasts :mad:

Seems to be more potential fun brewing up for mid December. Bring it on

Danno

Earthman wrote:

Yeah,I've been noticing all the chatter elsewhere about that.

What I find interesting about the coolness is how much easier it will be for an actual cold snap to take effect quicker when we are already well cooled down.

I disagree, I remember last December 24th, 13.6c in Killarney while it was 1.8 in Portlaoise and snowing!

A subtle change in wind makes all the difference.

Also, remember how the three week cold snap around Christmas 1995 came and went? Trees were in full leaf at the start of December, snow from Dec 21st to Jan 11th and then 12c on Jan 12th 1996???

Danno

Danno wrote:

I disagree, I remember last December 24th, 13.6c in Killarney while it was 1.8 in Portlaoise and snowing!

A subtle change in wind makes all the difference.

That was an entirely different scenario.
what exactly is it that you are disagreeing with?
I said that its easier for temperatures to drop given the right conditions when they are already low.

How could you disagree with that ? :rolleyes:

Danno

It does not have to be already cool for temperatures to easily drop further, we are an island in the atlantic whose temperatures are determined by the origins of airmasses, albeit slightly tempered by the seas.
One day we can have 15c and rain, the next day or even six hours later we can be in 0c and snowing, we do not generally see depreciation of temperatures over a wide timeframe as happens on the continent.

Danno

Danno wrote:

It does not have to be already cool for temperatures to easily drop further, we are an island in the atlantic whose temperatures are determined by the origins of airmasses, albeit slightly tempered by the seas.
One day we can have 15c and rain, the next day or even six hours later we can be in 0c and snowing, we do not generally see depreciation of temperatures over a wide timeframe as happens on the continent.

So what were you disagreeing with?
I never said it has to be cool for temperatures to drop-that would be silly.

I said it is easier for them to drop ie go colder when its already cold.

I made a statement of encouragement for cold lovers, in that, its already cool.
A cold incursion into something already cold will have more effect than into something warm.

You immedietely said " I disagree" and proceeded to address something I didnt say at all...

Danno

Regardless of what way the weather is now, i.e. 20c or 10c, if tomorrow a cold airmass moves in, it will be 0c then, regardless of the temperature now!

For example, if it is 10c today, tomorrow the cold snap comes in and it is 0c.

Now if it is 20c today, tomorrow's cold snap will still bring 0c, not 10c as I feel you are proporting in your statement

Danno

Danno wrote:

Regardless of what way the weather is now, i.e. 20c or 10c, if tomorrow a cold airmass moves in, it will be 0c then, regardless of the temperature now![

For example, if it is 10c today, tomorrow the cold snap comes in and it is 0c.

Now if it is 20c today, tomorrow's cold snap will still bring 0c, not 10c as I feel you are proporting in your statement

With respect thats rubbish.
By that definition when a cold mass comes in the temperature will be the same in Mallin head as in Valentia.
Or that a northerly plunge down through Europe will have the same effect in copenhagen as in Nice.
It wont.
And the reason?
Simple-as I said, it takes more cold and deeper cold to affect 20c than it does 10c.

Danno

Ah Earthman, come on! The airmasses push each other out of the way, thats why we get rain for heavens sake!

And yes, when an airmass is in siteu over Ireland, our temperatures are relatively uniform, obviously up to 4c local variations will exist, but still a largely uniform airmass.

Our landmass and the same goes for the UK is not large enough to generate airmasses, Iberia is nearly the smallest landmass that generates it's own airmass.

So the fact remains that it is the origins of airmass that determine our weather, not depreciation of temperatures over a large timeframe.

The only help that the current cool spell would have on any cold snap is to be more favourable to snowfall actually sticking as soil temps are depressed, that is all though.

Danno

Danno wrote:

Ah Earthman, come on! The airmasses push each other out of the way, thats why we get rain for heavens sake!

And yes, when an airmass is in siteu over Ireland, our temperatures are relatively uniform, obviously up to 4c local variations will exist, but still a largely uniform airmass.

7 posts back, you gave an example of a 9c difference.

Our landmass and the same goes for the UK is not large enough to generate airmasses, Iberia is nearly the smallest landmass that generates it's own airmass.

But that doesn't change the fact that cold air entering an environment with warm air will have less of an effect than when it enters an environment with already cold air.

So the fact remains that it is the origins of airmass that determine our weather, not depreciation of temperatures over a large timeframe.

You keep saying that... but it has nothing to do with what I said that you initially rushed in to disagree with.

The only help that the current cool spell would have on any cold snap is to be more favourable to snowfall actually sticking as soil temps are depressed, that is all though.

Thats not correct.
You bring a cold air mass down over a warm air mass and its tempered.
The northerly we had last week delivered more to scotland than Ireland, just as an Easterly delivers more to Kent than it does to Carlow in terms of cold.
Reason? longer track(same air) and its tempered by the environment.
when it's already cold, theres less tempering.

lucernarian

Earthman is right according to the 2nd law of Thermodynamics.
Heat energy goes from a hot object to a cooler area.

Something warm will always cool down. Something cool will gain heat from warm objects around it. The airmass that (hopefully) will travel over us from Siberia will be warmed on its way here. This cool spell affected more than just the island, it helped cool the North Sea and the Atlantic that's north and then east of us.

Of course, by the same logic, if there is colder weather over Ireland, then heat energy will move more quickly from warmer regions to Ireland. In other words, it gets progressively harder and harder to cool something more and more. Even with our current cool weather, it will be difficult for Ireland to have ice-day weather in the future.

Danno

@TBC: So were damned if we do, and damned if we dont!!! LOL

@ Earthman: The 9c example I gave is very valid because the cold airmass was not in siteu over us at the time, it was merely "on the way" it does though back up what I am trying to point out, Killarney could have been at 23.6c and Portlaoise would still have registered 1.8c. We had two airmasses over the country at the time.

The airmass was tempered from perhaps -10c at its origin over Greenland to +1.8c over Portlaoise, whereas the 13.6c airmass over Killarney was tempered from say +18c over the Azores to +13.6c.

Now had Portlaoise been at an already -2c when that Greenland airmass moved down from the north, temperatures would have actulaay risen to +1.8c as registered there on the day due to the "fetch" over the warmer seas.

To finalize, what we need to have ice days in Ireland is a good airmass source from beyond this island, regardless of whatever heat or cold that is already here before it arrives, it will only be as cold as how much tempering it gets by the seas it gets on its journey here. If it is +20c or +10c here beforehand it will have no effect on how cold the incoming airmass will be.

Rain fronts mark the boundary and mixing of airmasses, usually under 200 miles in thickness. Over a landmass as small as Ireland and the UK who cannot generate their own airmass - we are at the mercy of imported weather conditions tempered by the seas which gives us our varied and wacky weather! Where ever the wind blows from sums up our weather.

Danno

Danno wrote:

@ Earthman: The 9c example I gave is very valid because the cold airmass was not in siteu over us at the time, it was merely "on the way" it does though back up what I am trying to point out, Killarney could have been at 23.6c and Portlaoise would still have registered 1.8c. We had two airmasses over the country at the time.

But that has nothing whatsoever to do with what you were trying to disagree with me on...
Why do you persist in making a point about a competely different thing than the tempering of airmasses?

The airmass was tempered from perhaps -10c at its origin over Greenland to +1.8c over Portlaoise, whereas the 13.6c airmass over Killarney was tempered from say +18c over the Azores to +13.6c.

Now you are learning which is a good thing.
The colder it is over Ireland, the more effect an even colder air mass will have when it plunges in here.

Now had Portlaoise been at an already -2c when that Greenland airmass moved down from the north, temperatures would have actulaay risen to +1.8c as registered there on the day due to the "fetch" over the warmer seas.

You're losing it again.Inland areas will always be colder than coastal areas.Land retains heat by day and loses it faster by night than the sea.

To finalize, what we need to have ice days in Ireland is a good airmass source from beyond this island,

We need that alright

regardless of whatever heat or cold that is already here before it arrives, it will only be as cold as how much tempering it gets by the seas it gets on its journey here. If it is +20c or +10c here beforehand it will have no effect on how cold the incoming airmass will be.

Incoming? My original point several posts back was with regard to the effect of an airmass on an already cooled down existing airmass and its environs.You ran in with an "I disagree" for the sake of it and nothing else.
It still looks like that as all you've done to be honest in the next few posts is waffled on about something that has nothing to do with the point I made.

Rain fronts mark the boundary and mixing of airmasses, usually under 200 miles in thickness. Over a landmass as small as Ireland and the UK who cannot generate their own airmass - we are at the mercy of imported weather conditions tempered by the seas which gives us our varied and wacky weather! Where ever the wind blows from sums up our weather.

More waffle unrelated to the point that I made-stop digging...
My point was simply that its already cold not mild so if we have a cold plunge now, it will have less work to do to drag temperatures down.
Basically it should mean a cold plunge now will bring temperatures down further than when it would if it was warmer.

Danno

Earthman wrote:

Basically it should mean a cold plunge now will bring temperatures down further than when it would if it was warmer.

That is what I am disagreeing with.

Danno

Danno wrote:

That is what I am disagreeing with.

Well you have shown no basis to disagree with it.
In fact to disagree with it is illogical for the reasons I've already stated.

Danno

Shall we agree to disagree then?

Don't know what to say to you to be honest...

Anyhow thread closed-part three about to be opened and stickified.