Turning progressively colder through the week, Very cold with snow showers later

nacho libre

Deep Easterly wrote: »

Tonight's ECM keeps the cool, slack northerly going for an extra day or so, but apart from coastal showers, which may not necessary be 100% snow, I am thinking another quite, cool spell with some night time frosts at best, which will be most severe in the south due to the direction of the wind. I cannot be excited about this upcoming spell yet, but plenty of scope for upgrades in later runs.

Has been a terrible winter for snow in my patch, I have seen more in one day in milder winters than for the entire period in this this cold one. A good storm or 5 would compensate nicely but nothing but mild, HP based south westerlies showing up on the long term ECM tonight. :mad:

well, i got a little bit more than you, but, considering how exceptionally long the cold lasted, the snow return at lower levels was crap for much of the country. As you say we've sometimes seen more snow accumulate, from a northerly airflow in late february, during a predominantly mild winter.

regarding this cold spell, it maybe well be that when it gets cold enough for snow to fall the energy to produce it is not there. so we could well end up on Sunday with wintry showers along the west, north west and north coast, with the rest of the country dry. As we know from the big freeze, and indeed past years, more often than not fronts coming from the north tend to make things the wrong side of marginal for snow at lower levels. So i'm not holding my breath for snow on Saturday either.

so let's hope as the cold northerly air arrives it stays fairly windy:)

jambofc

not really getting to excited about this,doesn't look like there is to much in the way of precip around and ground temp's don't really look to cold in the daytime,not going to last long enough to give to much,pity as my snow amount was a dusting in the whole of the last cold spell
oh if only we were a few hundred miles east.....

Snowaddict

Morning everyone,

Models tend to over-react & be unstable when we are dealing with marked developments at the 30mb Level.. Even on the ECMWF Operational evolution last night, there was a clear strong area of positive height anomolies centred to the far Northeast in the form of a Siberian High. Over the coming 5 Days, we should begin to a see a gradual area of positive height anomolies forming over the Pole, intereacting to form a largescale blocking High to the Northeast.

Subsequently, longwave pattern developments also support the notion of a strong area of positive height anomolies centred to the variable North, Northwest & Northeast.

The initial northerly flow later this week into the weekend, is in my opinion, a direct response to the immediate warming at the 30mb level, the downwelling from which is already in evidence:

Zonal Wind Anomoly Time Series



The 30mb Temperature has warmed significantly in the past 5 Days, as is clear from the latest 30mb Temperature profile chart. This is indeed a very significant warming & we can have confidence that at least some largescale blocking will develop as a by-product from this warming event. Further warming is indicated over the next 7 - 10 Days after a brief lull in the level of significant warming.



The exact position of any largescale blocking will be uncertain but I think that overall, the background signals used some 4 Days ago predicted the coming Northerly flow fairly well. It will be turning increasingly colder later in this week, with the threat of wintry showers at times, especially in exposed Northern and Northwestern areas. The main feature will be harsh, to perhaps severe frosts developing at night time, with minima of -5 possible in several areas.

Further ahead, overnight 00Z Guidance is exceptionally positive, indicating Northward Warm Air Advection, with a further Easterly/Northeasterly flow developing in the long term.

After the Northerly flow later this week, another Polar Maritime Northwesterly flow should then follow, followed by a gradual rise in pressure with conditions remaining cold rather than mild overall. There is the potential in the 10 Day timeframe for another renewed incursion, however that is some distance out yet.

ECMWF 00Z - T+240



CPC Medium Term 500mb Prognostic Chart

http://www.cpc.noaa.gov/products/predictions/814day/814day.03.gif

An interesting period of weather ahead, with lots of potential & a solid major warming has taken place at the 30mb level. This is a positive indeed, but does not, as always, 100% Guarantee a cold outbreak further ahead, but it does increase the chances markedly. The location of any subsequent largescale blocking will also be uncertain.

SA

forkassed

Hmmm..tasty stuff indeed, maybe we'll get another proper blast of winter





Also..heres a nice animation of the strat warming taking place

darkman2

The strat warming will take at least 7 days to propagate to 1000hpa level. 6z ensembles show an average of almost -10 at 850 level near the end which I don't think I have ever seen before at this distance.

thecretinhop

Hi all, there seems to be a chance of snow again:rolleyes:? hmmm, very let down in west last time, any one any idea will it be here by saturday two weeks i have a wedding to go to!

forkassed

Another GFS run to drool over, some snow potential in the nearer time frame but then things just go nuts for the 2nd week of February

Not

Parts of the north west of Meath seem to have had a dusting in the last day or so.

darkman2

My view of todays model outputs is that we have in fact already started a new and potentially severe period of weather similar, if not potentially even more severe then January in the next couple of weeks. There is now no sign of mild weather on the horizon and the output continues to get colder.


ECM at 120hrs which is Sunday



Very cold with snow showers. Frosts becoming severe this weekend with ice reforming on surfaces. Lying snow this weekend in the North and Northwest in particular.


Into Monday




Further snow showers. Cold air will be hard to shift by approaching fronts from the Atlantic. Think the ECM will show a snow event here and probrably a continuation of the very cold weather as pressure builds to the North.

Redsunset

12Z ECM rolling out,

120 has the low buried into scottish coast

darkman2

168




216hrs

Some serious stuff right there.

THE BIG FREEZE RETURNS FROM THURSDAY









Let's hope the Government is prepared this time.

irishdub14

There is now no sign of mild weather on the horizon and the output continues to get colder.

I've heard that one before, and then all the snow melted.....!!!

Pangea

darkman2 wrote: »

THE BIG FREEZE RETURNS FROM THURSDAY

Lol wow, this could possibly be one of the biggest letdowns ever if this doesnt happen especially after reading those posts.
Fingers crossed.

nacho libre

Pangea wrote: »

Lol wow, this could possibly be one of the biggest letdowns ever if this doesnt happen especially after reading those posts.
Fingers crossed.

perhaps it's time to consult your postman friend senor Pangea?;)

darkman2

Pangea wrote: »

Lol wow, this could possibly be one of the biggest letdowns ever if this doesnt happen especially after reading those posts.
Fingers crossed.

The more serious weather is still at least a week away and by definition is not gauranteed to happen like that but in the meantime frost and ice likely to be the issues over the weekend and some snow esspecially in Northern counties.

nacho libre

the eagle mentioned the wintry showers would chieflly be in the north at the weekend, but the charts showed weak troughs passing down across the country on saturday. so whatever about the rest of us, you'll more than likely see snow at the weekend senor pangea, as will grace7.

Takeshi_Kovacs

darkman2 wrote: »

168




216hrs

Some serious stuff right there.

THE BIG FREEZE RETURNS FROM THURSDAY









Let's hope the Government is prepared this time.

I thought, that this upcoming cold spell was only going to be a brief interval, before normal westerlies brought mild weather back again?

Pangea

Great, theres still a good bit of snow lying around the hills in parts around here,
as the old people used to say " When the snow is lieing around like that its waiting for more to come"

darkman2

Takeshi_Kovacs wrote: »

I thought, that this upcoming cold spell was only going to be a brief interval, before normal westerlies brought mild weather back again?

Not anymore...;)

H2UMrsRobinson

Oh be still my beating heart, it's like music to my ears...ok enough of the cliches.

After the letdown last time I'm not getting my hopes up just yet, but judging by the expert opinions of my fellow boarders things are starting to hot up..or is that cool down? well you get my drift!...:D

nacho libre

Pangea wrote: »

Great, theres still a good bit of snow lying around the hills in parts around here,
as the old people used to say " When the snow is lieing around like that its waiting for more to come"

i've heard that saying before. by the way get ready for the moaning...if it does turn cold again;)

Pangea

nacho libre wrote: »

i've heard that saying before. by the way get ready for the moaning...if it does turn cold again;)

Yes a lot of those old sayings are true,
People will always moan i guess, like us moaning for the other 11 months of the year when there is no snow.
:P

Deep Easterly

I like the outer reaches of the ECM tonight:



A polar continental, nice one. :cool:

nacho libre

Deep Easterly wrote: »

I like the outer reaches of the ECM tonight:



A polar continental, nice one. :cool:

so you've forgotten about the lack of storms now:p

Min

So a national emergency coming up when Dublin gets an inch of snow.....

I don't miss the ice and snow, it was just hardship and lots of extra work plus the snow lasts too long around here, I can still find the remains of a snow drift from the blizzard two weeks ago.

I like the current weather.

Deep Easterly

nacho libre wrote: »

so you've forgotten about the lack of storms now:p

Trust me Mr. Mayo, I have not. A disgraceful winter for storm activity thus far. I am almost embarrassed to say that my max wind speed is a paltry 45mph so far this month. Still, the west will awake sometime before the winter is out I hope, and when it does, there is no other place I would rather be!

Iancar29

Sky news weather just showed the possible wintry scene for the weekend,
looks like saturaday we ll be in the same situation as last time ,hopin that the wind will push the fronts in off the Irish sea.
So ye.... The FReeze: Part II , The cold fights back !


I do wonder tough if it gets in anyway bad how would it effect those starting mac exams next week.They should start making arrangments.

Deep Easterly

Can't judge the rest of the country by this, but the ECM has me down for a few light rain showers this coming weekend, with temps of 5c/6c by day and barely falling below 0c by night.

http://www.yr.no/place/Ireland/Galway/Tuam/weekend.html

Pretty much the same as currently really.

M.T. Cranium

I can see some similarities developing in the next 2 weeks to the pattern seen in the second half of Feb 1933 when Ireland had what I am told was its most severe snowstorms on record. Looking at the maps I have to imagine these were around the 24th to end of the month. What's quite similar is that a week to ten days before this, the flow was northerly around a strong retrograde high near 35W as per all the guidance for this weekend. Then, although it's not day by day exactly similar, the northerly slowly gave way to an easterly with low pressure forming over Germany and spreading west across southern England.

A couple of weeks ago I was thinking perhaps the cold would return briefly then it might turn milder in February. That was partly based on the El Nino pattern strengthening in early January, but now it seems to be rapidly fading and there has been quite a strong warming event in the stratosphere.

It wouldn't surprise me now if February turned bitterly cold and you would have to think the odds are probably better than 50-50 that if it does so, a significant snowfall will develop. The Feb 1933 cold was not all that intense, looking at the CET records there were days near zero but nothing really as cold as what we're seeing on the current charts where CET days could easily get down to -5 or lower (around the 8th-9th on the current GFS run).

Now I realize that these model runs get into high uncertainty past five days, but often you get a glimpse of some future reality, even if it is going to have different details or timing. So I'm beginning to think that the winter of 09-10 may now transition from significant to memorable or even extreme. Some would say it already has been memorable (I would agree) so I guess I am pointing at extreme here -- and if so, this forum is going to get super busy.

Su Campu

Go easy lads, it's way too marginal this weekend to be even mentioning the Xmas spell in the same paragraph!

We'll be sitting right bang in between the high to the west and the low to the east, with a strong northerly jet down the area. The models are fairly consistent in their positioning. Certainly the UK and Benelux/Germany are looking set for some real cold, with the possibility of polar low formation in the North Sea, but the further west you go conditions really do become very mariginal indeed, and depending on the minute details of the setup - the high encroaching or retreating a a couple of degrees longitude - it's going to be a nowcast situation for most. We don't quite get the cold mid to upper temperatures we got before, so the showers that develop to our north will do well to penetrate any decent distance southwards, with the biggest chance of heavier and wintrier ones in the East.

In any case, from Monday the models start to diverge slightly - the ECMWF tries to hold onto the northerly, swinging it around to an easterlyby midweek, while the GFS, UKMO, NOGAPS, GEM and JMA all have a Bartlett high bringing milder westerlies. Interesting opposition to the ECMWF, let's see how it pans out as the week progresses.