Model Output Discussion - 19th - 25th December

[Cumulonimbus Tower]

To be fair I think it is a matter of perspective and location. I had to get a set of winter tyres fitted for going over the moor to my little boys nursery last week as on about four different occasions the road was treacherous due to snow and ice and by the look of the charts it should be quite wintry on Tuesday night, Wednesday, early Thursday and again on Sunday if the charts verify. So whilst not a mega cold spell to compare to last December it’s certainly been a lot better than some years of daily double digits and no snow for even the Cairngorms. I think some doom mongers on here have forgotten how bad things can actually get in this country. Happy Christmas

[shedhead]

No they don't, anyone who has read their comments in recent weeks will realise there is something colder to look forward to in the new year, even if it's mid to late jan.

I don't disagree with the above PL, but there is quite a difference between 'something colder to look forward to in the New Year' and 'patience will be rewarded in spades in the not too distant future'

[penicuikblizz]

I am having a laugh to myself after looking at the models right now!! Where is the Artic? No Siberian winter we were supposed to have? So many people have got it so wrong!!!

[Frosty.]

I don't disagree with the above PL, but there is quite a difference between 'something colder to look forward to in the New Year' and 'patience will be rewarded in spades in the not too distant future'

well since it's christmas i'm trying to balance out all the negative posts with something positive and I still feel the models are going to start looking a lot better for cold fans soon, the news from the strat thread just reinforces my view that there will be some wintry weather in january and not weeks and weeks of swlies.

[Snowstorm1]

I am having a laugh to myself after looking at the models right now!! Where is the Artic? No Siberian winter we were supposed to have? So many people have got it so wrong!!!

Not really most forecasts showed Mild December and then getting progressively colder in general and besides this discussion should be in the Winter Forecasts Thread I think?

[chionomaniac]

Discussing whether or not it will be cold or mild later this winter is hardly on topic. I promised not to delete posts as it is Christmas........

[shedhead]

well since it's christmas i'm trying to balance out all the negative posts with something positive and I still feel the models are going to start looking a lot better for cold fans soon, the news from the strat thread just reinforces my view that there will be some wintry weather in january and not weeks and weeks of swlies.

With respect PL. Just because someone posts a comment about mild weather shown in the model suite does not automatically mean said post is negative, nor is it nescessarily a 'wind up', which is another term you and some other tend to use. If you don't want to comment on the models when they show a predominence of mild weather then that's your perogative, but as I've said before posting comments 'you' consider to be positive can prove both confusing and misleading to new or less experienced - especially when you add the misquotation of other respected members to the mix.

Edited December 24, 2011 by shedhead

[Grimsby Snow Lover]

well since it's christmas i'm trying to balance out all the negative posts with something positive and I still feel the models are going to start looking a lot better for cold fans soon, the news from the strat thread just reinforces my view that there will be some wintry weather in january and not weeks and weeks of swlies.

I do really admire your optimism PL. Having read the latest metoffice update today it really paints a very drab picture with mild/wet spell of weather for the foreseable up to the 22nd of January. Am I right in saying that they will not be considering any stratosphere warming until it actually occurs. If this is the case is this why they only really see mild in their models at the moment.

The latest NAO forecasts still suggest a more neutral forecast as we head into January. This to me would suggest a less active Northern Atlantic than we will be seeing this next week unless I have misunderstood them. The latest AO forecasts shows a lot of uncertainty, with quite a range of outcomes. Vast majority though remain positive at present.

http://www.cpc.ncep....index_ensm.html

http://www.cpc.ncep....ndex_ensm.shtml

Edited December 24, 2011 by Grimsby Snow Lover

[IDO]

No they don't, anyone who has read their comments in recent weeks will realise there is something colder to look forward to in the new year, even if it's mid to late jan.

The latest Weatheronline forecast, that goes to the last week of January (issued yesterday) has HP still dominating our weather; ends on the 24th. Maybe "some fog & frost", hardly what patrons expect when you suggest "cold".

Can you post models that show cold weather for mid Jan through Feb please? Or is it a hunch? The Law of Probability? Tea Leaves? I would say there is no greater chance of seeing cold this Feb than any other year; if anything I would lobby contrary to your statement: the CET for 2011 is likely to be the second highest ever thus suggesting a pattern of warmer temps. If it is based on stratospheric warming then this is unlikely to happen till Feb, as the models are now downgrading the current indications, and the next alternative is mid-Jan...and of course that maybe downgraded. Then, we have to hope the warming goes to the lower levels, which may take 2/3 shots. Then we have to hope the block(s) build in the right place and by then we are near Springtime.

Now I am not precluding a snow event in the second half of winter, but this is a model thread and nothing in the models are indicating a juxtaposition of the current synoptics, and relying on a possible warming event should be judged if and when it happens.

The previous statement is meant in good nature and may stray off topic. Although they are strongly worded they reflect the nature of my writing and are not meant to damn or incense any member. They are my thoughts and may or may not be judged as the ramblings of a mad man when we have the benefit of hindsight. A Merry Christmas to all.

[Craigers]

All this uncertainty and lack of cold outcomes reminds me of early last november as it was a mild start to the month and charts looked dire with all the doom and gloom then all of a sudden the charts switched to a beasterly with a lot of the unexpected. Just hope this is the case this year

[Mark Neal.]

Well the models look dire and poor to say the least at the moment in regard to seeing a severe snowy and cold spell. But we still have many weeks left of winter. I believe that our time will come and it is getting closer. I say give it untill this time next month and if we haven't seen a cold spell yet, then maybe then you can start to slag off winter, until then... Plenty to play for. Patience is a virtue.

Happy Christmas to everyone on Netweather

Mark

[Uncle_Barty]

All this uncertainty and lack of cold outcomes reminds me of early last november as it was a mild start to the month and charts looked dire with all the doom and gloom then all of a sudden the charts switched to a beasterly with a lot of the unexpected. Just hope this is the case this year

The change from mild and zonal last November wasnt unexpected (though the severity was, of course!) - upstream signals had pointed it to it, but it still came at fairly short notice (about 7-8 days) in the model output.

The situation as I see it now is:

* Average to mild, and zonal, with the possibility of rather cold shortlived incursions, until further notice.

* That "Further notice" may appear in the models at less then 10 days. I'm not convinced that it will appear deep in FI first.

* Because of the possible upstream changes, I am not looking beyond 8 days or so WRT the general upper pattern

* Although the pattern we are in is hard to break out of, no-one can say that it is set in for the winter (much as I would like it to be!)

[Craigers]

The change from mild and zonal last November wasnt unexpected (though the severity was, of course!) - upstream signals had pointed it to it, but it still came at fairly short notice (about 7-8 days) in the model output.

The situation as I see it now is:

* Average to mild, and zonal, with the possibility of rather cold shortlived incursions, until further notice.

* That "Further notice" may appear in the models at less then 10 days. I'm not convinced that it will appear deep in FI first.

* Because of the possible upstream changes, I am not looking beyond 8 days or so WRT the general upper pattern

* Although the pattern we are in is hard to break out of, no-one can say that it is set in for the winter (much as I would like it to be!)

That's basically what i was explaining about last year with the short notice in the model output. Good view on the current situation. End of next week

there should be some interest in the model output.

[TonyH]

My take on the Festive period weather with a regional slant:

Weather guide for Christmas Day to New Years Day (west Wales and the central Midlands)

Headline: Very mild for the Christmas period, then colder with some rain, milder for New Year.

Friday gave a good dose of rain for all, with over an inch falling on Llanwnnen and half an inch on Rugby. Nonetheless, it is going to end up the second driest year on record (back to the 1870's) in Coventry and Warwickshire, with under 500mm in total (average 650-700mm).

We are in a very mild South-west flow for Christmas Day and Boxing Day. Mostly dry, apart from perhaps some drizzle at time over west Wales, and both days likely to reach as high as 12c, after not falling below about 9c by night. Breezy.

On Tuesday night a deepening low will pass close to Scotland, so we should be seeing some rain crossing through Tuesday night into Wednesday, but probably not so much for the Midlands. Still mild.

Wednesday and Thursday will have colder north west to west winds bringing some showers or light rain at times and with sunny intervals between, temperatures close to the late December average of 7 or 8c, with slight frosts a possibility by night- should they be clear and calm enough. Probably turning milder during Friday which should be a mostly dry and bright day.

The GFS model has a large high pressure close to the south next weekend, which would then be mild and mostly dry although breezy still. However, a rather more unsettled weekend is foreseen by the ECM model, with some weak troughs crossing the country. For New Years celebrations then it's looking generally dry and mild, but with a chance of some rain at times.

For supportive models see the Wales thread:

http://forum.netweather.tv/topic/71920-wales-regional-weather-discussion-snow/page__st__440__gopid__2197172#entry2197172

[feb1991blizzard]

That's basically what i was explaining about last year with the short notice in the model output. Good view on the current situation. End of next week

there should be some interest in the model output.

But the Met office 30 dayer was suggesting well below average temps and sleet or snow for many areas particularly in the east, nearly a month before it happened so it wasnt entirely a short notice event, it must have been showing on the ECM long range ensembles.

And consistently i might add, there was no wavering and chopping and changing, it was forecast all the way in from about 600 - 700 hours out. I would say the Met offices finest hour when it comes to forecasting severe weather in my opinion, as accurate as i have ever seen a monthly forecast from anyone.

Edited December 24, 2011 by feb1991blizzard

[danm]

But the Met office 30 dayer was suggesting well below average temps and sleet or snow for many areas particularly in the east, nearly a month before it happened so it wasnt entirely a short notice event, it must have been showing on the ECM long range ensembles.

And consistently i might add, there was no wavering and chopping and changing, it was forecast all the way in from about 600 - 700 hours out. I would say the Met offices finest hour when it comes to forecasting severe weather in my opinion, as accurate as i have ever seen a monthly forecast from anyone.

That was last year, but there have been plenty of other times when their 30 day forecasts did not pick up a change to cold weather.

[leicsnow]

But the Met office 30 dayer was suggesting well below average temps and sleet or snow for many areas particularly in the east, nearly a month before it happened so it wasnt entirely a short notice event, it must have been showing on the ECM long range ensembles.

And consistently i might add, there was no wavering and chopping and changing, it was forecast all the way in from about 600 - 700 hours out. I would say the Met offices finest hour when it comes to forecasting severe weather in my opinion, as accurate as i have ever seen a monthly forecast from anyone.

If you want to know the exact date when Met Office outlook picked up on the cold at the end of November 2010, I can tell you with good confidence that the details came in the update on the 5th November.

That was last year, but there have been plenty of other times when their 30 day forecasts did not pick up a change to cold weather.

Yes, if I remember right they took a while to pick up on the cold at the start of Feb 2009. It may even have been as late as around the 28th January when the newspapers began to sing their little tune about it all.

Edited December 24, 2011 by Tellow

[feb1991blizzard]

If you want to know the exact date when Met Office outlook picked up on the cold at the end of November 2010, I can tell you with good confidence that the details came in the update on the 5th November.

Ok but the forecast went out 30 days so a very good effort to get a 30 day outlook that accurate.

[Frosty.]

I do really admire your optimism PL.

The latest AO forecasts shows a lot of uncertainty, with quite a range of outcomes. Vast majority though remain positive at present.

http://www.cpc.ncep....index_ensm.html

http://www.cpc.ncep....ndex_ensm.shtml

This is one case where being negative would be better than positive. The models show the north will remain unsettled with most of the rain and occasional hill snow whereas the south will be more settled at times with some frost and fog being closest to the continental high.

[A Winter's Tale]

If you want to know the exact date when Met Office outlook picked up on the cold at the end of November 2010, I can tell you with good confidence that the details came in the update on the 5th November.

Yes, if I remember right they took a while to pick up on the cold at the start of Feb 2009. It may even have been as late as around the 28th January when the newspapers began to sing their little tune about it all.

Winter Discussion, not Model Discussion Tellow!

[Roger J Smith]

The 12z GFS run has to be seen against the prospect of a fairly imminent stratwarm that seems 60-80 per cent likely in the range of one to three weeks. Without taking that into account, the run suggests a gradual breakdown of mild zonal flow more towards a southerly diving jet and a general slumping southward of a very large pool of cold air. If you factor in that somewhere in that evolution a more robust blocking could develop, then with all that cold air heading in the general direction of west-central Europe, there would have to be optimism about a pattern shift to very cold accelerating after New Years.

Although the stratospheric events are key, the surface development that is most promising in recent days is a strong arctic high over the Laptev Sea (approx 140 E from a source at 1060 mbs in east-central Siberia) that seems to be trying to ridge across the pole towards Svalbard to east Greenland. This could in fact be the opening round of necessary changes to get high-latitude blocking in place and force the circumpolar vortex to break up into powerful but lower latitude separate vortices.

I expect model runs to continue to oscillate and also for a large spread in perturbations due to this uncertainty over major pattern change. If we get an actual stratwarm then model evolution could become quite dramatic.

[shadowfax]

To be fair I think it is a matter of perspective and location. I had to get a set of winter tyres fitted for going over the moor to my little boys nursery last week as on about four different occasions the road was treacherous due to snow and ice and by the look of the charts it should be quite wintry on Tuesday night, Wednesday, early Thursday and again on Sunday if the charts verify. So whilst not a mega cold spell to compare to last December it’s certainly been a lot better than some years of daily double digits and no snow for even the Cairngorms. I think some doom mongers on here have forgotten how bad things can actually get in this country. Happy Christmas

I quite agree with you, last weekend we were toboganing my husbands "very unsuitable for snow" car down our drive in 5" snow. It is actually quite nice to have a Christmas this year were we can actually drive around safely, ride the horses and walk the dogs without the arctic gear on and not try to be the emergency plumber when the pipes burst and no one will come out because it's Christmas!!

Of course a little bit would be nice but maybe next weekend!

[Frosty.]

The Gfs 12z op run is not the best run for cold weather, infact it's a very mild run for southern britain although there is a brief cool snap later next week before it turns much milder again in the run up to the new year. FI is very unsettled with vigorous depressions crashing across the north of the uk with some very brief cold incursions flirting with northern scotland only, at least the post from RJS was a pleasant read compared to flipping through those mild charts frame by frame.

[Summer Sun]

ECM for the start of 2012 could be a lot worse for those after colder weather

http://www.wetterzen...cs/Recm1921.gif

http://www.wetterzen...cs/Recm2161.gif

http://www.wetterzen...cs/Recm2401.gif

Its not perfect for the coldies but things seem to be changing slowly.

Edited December 24, 2011 by Gavin D

[Frosty.]

ECM for the start of 2012 could be a lot worse for those after colder weather

http://www.wetterzen...cs/Recm1921.gif

http://www.wetterzen...cs/Recm2161.gif

http://www.wetterzen...cs/Recm2401.gif

Its not perfect for the coldies but things seem to be changing slowly.

Good charts for the scottish ski industry, not much use for anyone else. Edited December 24, 2011 by Polar_ Low