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Posted
  • Location: Castle Howard, North Yorkshire
  • Location: Castle Howard, North Yorkshire
Back on topic -

I quietly mentioned about Thurs last week that the outlook progged by the models of a quick breakdown to atlantic driven weather was way too progressive and overcooked, especially the ECM which IMO is performing disappointingly poorly these days, and that it would be no surprise to perhaps see a more continental influence to our weather through February.

The possibilities of that happening have been developed by the models and FI has remained at four days ahead for several days now. On this score it was predictable (but of course correct) for the METO to put out their forecast as they have for the week ahead.

It was always going to be the case that the models would not be able to handle northern blocking and that projected jet forecasts by the models of last week were rather going to go out of the window. A good illustration of not paying total lip service to them.

The outcome is still very uncertain, even more so, but the odds have increased on a complete change of pattern this month. It is significant to see indications of the indices AO and NAO looking to trend negative over the upcoming period and this maybe a reflection of the way ahead.

The atlantic may still push in, at least briefly by next weekend. The models will continue to try and break the cold spell down at every opportunity anyway. But it is worth bearing in mind though how well the UKMO has plotted the development of this cold spell this week and this should be noted with a fantastic 00Z ouput as much as the dreadful ECM reverting back to a quick 'kill' this morning. Way too progressive the latter... yet again? We will see.

There is an increasing chance now though,IMO, that cold dry air may finally be the winner in the end after this long very poor first 2/3 (and a bit) of the winter.

Tamara

Hi Tamara,

Good post. Yeah great call by you earlier in the week, to spot the blocking to the East,

and the halt of the Atlantic.

As you mention it is refreshing to see at last the prospects of some winter style temperatures.

Like you I favour the eventual outcome being cold and dry particlarly if all this results

in a South Easterly.

TEITS posted the AO/NAO forecasts last night and I was suprised to see the change towards

-ve which can only help our chances of blocking to the North.

I think these are wonderful times for us model watchers , and has been edge of the seat stuff

recently.

I think it is great to see the board in such a positve mood after all the understandable gloom

during the early part of Winter.

Regard the Met Office forecast I don't think there was much else they could say under the circumstances.

Brian :)

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Posted
  • Location: Eastbourne and Larnaca,Cyprus .
  • Location: Eastbourne and Larnaca,Cyprus .
Morning/afternoon nick :)

That is very good to here - hopefully backs up the point I just made about the ECM being way too progressive again perhaps. I cannot understand the difference in modelling over Scandi - it is very worrying to have such big differences between the models in such a short timeframe.

I know it keeps showing us what we want to see - but the UKMO has still handled this best of all IMO - so far.

Tamara

Yes it is a worry why that ecm would be so awful this morning, it pushes that low in so quickly compared to the other models, the only support I can find for it is the gem at 96hrs, the gfs 00hrs ensembles didnt have one single member that backed it either so its all rather strange. At the moment there are 4 models against it and its own ensembles so being realistic it doesnt have much support, if its picked up a new signal then that would just sum up the winter so far! but its quite key how the ukmo havent backed this also if you're looking for the tiniest of signs about the trend for today the latest ukmo 48hr model slightly strengthens the ridge from the ne compared to the equivalent time from its 00hrs run, only by a couple of millibars but small differences earlier can make a big difference in such a knife edge pattern. :)

Edited by nick sussex
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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks
Not much to get excited about in that little lot really. Snow is pointless if it's going to turn to slush and rain after a couple of hours.

read my latest blog for you and also our alert?

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Posted
  • Location: Louth, Lincolnshire
  • Weather Preferences: Misty Autumn days and foggy nights
  • Location: Louth, Lincolnshire

Certainly for Eastern counties SSTs in the North Sea are still above average which makes low-level snow in these areas marginal at best - though obviously cooler temperatures this week will help a little bit. I remember February 2005 and am yet to be convinced that a re-run of that event won't be the end result from this. I accept that Inland areas could do well though.

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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North
read my latest blog for you and also our alert?

Thanks John, I will have a look now. :)

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Posted
  • Location: IPSWICH, SUFFOLK
  • Location: IPSWICH, SUFFOLK

well it may turn to rain but this is the same situation we had in late december 05, when the atlantic came back in. It's just a question of how much and how far it will travel. It'd be nice to see alot of snow in my area as we haven't really seen anything this winter unfortuantely. Another decent question is how slow will the atlantic low travel, the slower the better as it will surely be carrying alot of moisture. So hopefully the warmth doesnt undercut the snow so to speak

---when you say knife edge for coastal counties, I'm thinking a few miles in would be knife edge, but say 10 + miles you'd be ok I'd have thought---

Edited by Arrows
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Posted
  • Location: Castle Howard, North Yorkshire
  • Location: Castle Howard, North Yorkshire
Well a possible classic set-up this week. I strongly agree with Stephen P, it is far from nailed on what will happen midweek onwards but it's hard not to recall throwbacks to the eighties when looking at the charts.

I have to say it is wonderful for you and Stephen to be in full agreement regards the potential for next week

like you I am going to remain cautious.

But it's difficult to not get excited.

Brian. :)

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Posted
  • Location: Lincoln, Lincolnshire
  • Weather Preferences: Sunshine, convective precipitation, snow, thunderstorms, "episodic" months.
  • Location: Lincoln, Lincolnshire
Well a possible classic set-up this week. I strongly agree with Stephen P, it is far from nailed on what will happen midweek onwards but it's hard not to recall throwbacks to the eighties when looking at the charts.

Agreed- the throwbacks to the Eighties are certainly apparent. I'm particularly struck by the persistence of relatively high pressure around Iceland/Greenland on the outputs and tendency for high pressure anchored over Scandinavia to throw up a ridge across to that area- unusual in recent years.

After recent months I would often favour the ECM but it has to be said that the Atlantic coming in happens in FI (especially given that FI seems to be around T+72 at the moment!) and the ECM has not performed all that well over the past two weeks with a recurring tendency to overdo the northern arm of the jetstream.

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Posted
  • Location: Norfolk
  • Location: Norfolk
Certainly for Eastern counties SSTs in the North Sea are still above average which makes low-level snow in these areas marginal at best - though obviously cooler temperatures this week will help a little bit. I remember February 2005 and am yet to be convinced that a re-run of that event won't be the end result from this. I accept that Inland areas could do well though.

Although the January cold snap had no issues depositing snow for EA - its was the NE that seemed to inheret the snow forcefield.

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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North

I suspect that the experts are going to struggle badly this coming week as this is an unusual situation for them. Normally we get nice easy topplers followed by mild but this is an entirely different situation with many wonderful possibilities that won't be nailed until the event is upon us. Some areas could see some mammoth snowfall depths.

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Posted
  • Location: Broadmayne, West Dorset
  • Weather Preferences: Snowfall in particular but most aspects of weather, hate hot and humid.
  • Location: Broadmayne, West Dorset
Historically it is not a set-up that favours Ireland (rain likely fairly quickly once the PPN sets in ), South of the M4 (often too borderline for snow) or the far East (PPN dying out before it gets there). But the strong caveat is that we don't know for sure how the low pressure systems will track. If a slider develops in response to building pressure to the North, then the greater chance of more areas being in the cold air for longer.

All in all fascinating stuff, and a whole lot better than watching the northerly jet wind itself up again and an Azores/Bartlett combo - although I'm sure WIB would disagree !

Very fascinating Ian. This scenario has Feb 1978 written all over it to me. I personally feel that even the meto and( apologies for mentioning it) countryfile forecast have been to progressive in the north-east movement of the precipitation. The last chart on the CF forecast was a dead ringer for Feb 18/19 1978.

On that occassion here in Dorset we got 18 inches of level snow blwon into 25 foot drifts !!

Ive only waited 29 years to see another chart with that sort of potential.

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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North
I have to say it is wonderful for you and Stephen to be in full agreement regards the potential for next week

like you I am going to remain cautious.

But it's difficult to not get excited.

Brian. :)

Hi Brian,

Hope your area gets a good snowfall later in the week, you have always been optimistic and you deserve rewarding. :) This is going to be potentially the most stunning week meteorologically speaking for a long time. :)

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Posted
  • Location: Castle Howard, North Yorkshire
  • Location: Castle Howard, North Yorkshire
I hope you are resting properly, looking after yourself and not sitting up too late watching the early morning model output ?? Aunty Tamara is checking on you! :)

Tamara

Thanks Tamara, :)

Well I'm trying to rest, but finding it a little difficult to stay away at the moment.

I wouldn't of missed this for anything.

Actually I think model watching is my medicine

At the moment I'm taking one Scandi High four times a day :)

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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North
The UKMO has been in fine form of late, the ECM is a concern but as Nick says, the operational run does not appear to be representative of its own ensembles.

Yes, the forecasters prefer the mild air toppling in from the NW for a boring breakdown. This looks a wholly different beast !

Hi Ian,

I'm glad to see that you seem much more optimistic about the coming week, some reward for your LRF. :)

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Posted
  • Location: IPSWICH, SUFFOLK
  • Location: IPSWICH, SUFFOLK
Very fascinating Ian. This scenario has Feb 1978 written all over it to me. I personally feel that even the meto and( apologies for mentioning it) countryfile forecast have been to progressive in the north-east movement of the precipitation. The last chart on the CF forecast was a dead ringer for Feb 18/19 1978.

On that occassion here in Dorset we got 18 inches of level snow blwon into 25 foot drifts !!

Ive only waited 29 years to see another chart with that sort of potential.

I wouldn't get your hopes up as it's only sunday and this is progged for next week. I wouldn't worry what the charts say, I'll say after the event whether it wa worth the wait or not

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Posted
  • Location: Castle Howard, North Yorkshire
  • Location: Castle Howard, North Yorkshire
Hi Brian,

Hope your area gets a good snowfall later in the week, you have always been optimistic and you deserve rewarding. :) This is going to be potentially the most stunning week meteorologically speaking for a long time. :)

Hi Karl,

Thanks for those words.

I hope that everything pans out nicely for you, and everyone on here actually.

I think we are all weather enthusiasts on here and all deserve a taste of the magical

white stuff.

I did ok from the last cold snap so I don't want to be greedy.

If everyone else is happy then I will be.

Like you say, great times, great prospects and fascinating model watching. :)

Brian :)

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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North
I wouldn't get your hopes up as it's only sunday and this is progged for next week. I wouldn't worry what the charts say, I'll say after the event whether it wa worth the wait or not

After the winter we have mostly endured so far, we deserve a week like this, better late than never. :)

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Posted
  • Location: Broadmayne, West Dorset
  • Weather Preferences: Snowfall in particular but most aspects of weather, hate hot and humid.
  • Location: Broadmayne, West Dorset
I wouldn't get your hopes up as it's only sunday and this is progged for next week. I wouldn't worry what the charts say, I'll say after the event whether it wa worth the wait or not

Dont worry arrow my hopes arent too high. Just great to see cracking output for a change.

However the fact remains that in these rare synoptic situations the incoming fronts and dpressions tend to stall and even stop historically they stall over the south and southwest of England. Indeed the top three deepest snowfalls of the last 140 years have all occured over southwest england.

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Posted
  • Location: Tunbridge Wells, Kent
  • Location: Tunbridge Wells, Kent

The sypnotic comparisons to 47, 79 and the 80s are for once valid (a look at the archive charts can verify this for any doubters).

My only concern relates to how these sypnotics will pan out in 2007.

For example, in the eighties usually an 850 isotherm of around -5C or -6C aloft was pretty much guaranteed to deliver an event - today that is on the worse side of marginal with even -7C and -8C 850s often accompanying cold rain.

So maybe our snowless problem is twofold these days

1) We dont get the right set ups as often

2) When we do it has to be super cold because they don't deliver at the same temp as they used to

I'd love to be proved wrong (not least to reign in some of the GW rampers) however I don't hold out much hope for my own Central London location

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Posted
  • Location: Newton Aycliffe, County Durham
  • Location: Newton Aycliffe, County Durham
Dont worry arrow my hopes arent too high. Just great to see cracking output for a change.

However the fact remains that in these rare synoptic situations the incoming fronts and dpressions tend to stall and even stop historically they stall over the south and southwest of England. Indeed the top three deepest snowfalls of the last 140 years have all occured over southwest england.

Which 3 snowfalls were these and what level depths were recorded.

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Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North
Dont worry arrow my hopes arent too high. Just great to see cracking output for a change.

However the fact remains that in these rare synoptic situations the incoming fronts and dpressions tend to stall and even stop historically they stall over the south and southwest of England. Indeed the top three deepest snowfalls of the last 140 years have all occured over southwest england.

Yes that is true, cornwall and devon have been known to see very deep snowdrifts from this type of scenario, I hope every single one of us wil see some lovely snowflakes in the week ahead. :)

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Posted
  • Location: 4 miles north of Durham City
  • Location: 4 miles north of Durham City
Posted
  • Location: Glasgow
  • Location: Glasgow
The sypnotic comparisons to 47, 79 and the 80s are for once valid (a look at the archive charts can verify this for any doubters).

My only concern relates to how these sypnotics will pan out in 2007.

For example, in the eighties usually an 850 isotherm of around -5C or -6C aloft was pretty much guaranteed to deliver an event - today that is on the worse side of marginal with even -7C and -8C 850s often accompanying cold rain.

So maybe our snowless problem is twofold these days

1) We dont get the right set ups as often

2) When we do it has to be super cold because they don't deliver at the same temp as they used to

I'd love to be proved wrong (not least to reign in some of the GW rampers) however I don't hold out much hope for my own Central London location

Well you seem to have forgotten the snow that we had up here before the cold snap down south had pretty strange conditions. The 850 isotherm was around -1 or -2 and there was no 528dam line. But yet we still got snow.

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Posted
  • Location: Steeton, W Yorks, 270m ASL
  • Location: Steeton, W Yorks, 270m ASL
Agreed- the throwbacks to the Eighties are certainly apparent. I'm particularly struck by the persistence of relatively high pressure around Iceland/Greenland on the outputs and tendency for high pressure anchored over Scandinavia to throw up a ridge across to that area- unusual in recent years.

After recent months I would often favour the ECM but it has to be said that the Atlantic coming in happens in FI (especially given that FI seems to be around T+72 at the moment!) and the ECM has not performed all that well over the past two weeks with a recurring tendency to overdo the northern arm of the jetstream.

Not sure it's quite a "throwback" but there are certainly allusions in the general direction, and it's certainly the best looking set up at this sort of distance that I can recall for a few years, with the possoble exception of Christmas 05 and the NE'ly blizzard that disappeared at t-48h.

To be a really spectacular event the HP to the NE needs to ridge across more to Iceland, this slows the northward movement of fronts but does not hold them at bay. Bad news is the HP regressing slightly E / SE and allowing the fronts faster W-E passage. At present LP looks like winning out, and the interest is really in how slow the migration may be, and how intense and prolonged any snowfall at the margins.

At present I'd draw a line from the Wash to the Solway for Thursday night. Points NE of this line look favoured for snow, but it will be best on high ground and further NE. The heights don't look brilliant anyway, and further SW look just too high at present for worthwhile snowfall, certainly on low ground.

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Posted
  • Location: Tunbridge Wells, Kent
  • Location: Tunbridge Wells, Kent
Well you seem to have forgotten the snow that we had up here before the cold snap down south had pretty strange conditions. The 850 isotherm was around -1 or -2 and there was no 528dam line. But yet we still got snow.

I haven't forgotten that at all - as a recall the heights for that event were very low and as a consequence the freezing level was much lower than would be normal. Or course there will always be slightly freakish events like that, but the general trend over the last 20 years is for marginal events to increasingly fall on the rain side of the fence

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