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General Model Output Discussion

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Please continue. :)

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note that the GFS quirk is to overplay the strength of lows. at T78 the low was weaker than projected in 12Z and the heights to the north slightly further West. bin the rest of the run; will change.

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Ian Brown highlighted nicely the plan ahead. As I have said, attemtped breakdown from 12-20 but 14th onwards when fun begins. This will be 3rd major snow event for UK. It is going to be big snow for SW and S. Also note the 'sudden' increase of warning for heavy snow for SE this weekend. One has to ask why the meto have taken so long to to issue warning????? Some will post unniceties BUT I've been warning for some time for upcoming period and that there will be sudden upgrades in snowfall.

BFTP

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Right out in the far reaches of FI the arctic high muscles its way in, couldn't happen could it?

GP has recently done a very good post on the technical discussion thread and he is backing the cold to stay with us.

SS2

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Ian Brown highlighted nicely the plan ahead. As I have said, attemtped breakdown from 12-20 but 14th onwards when fun begins. This will be 3rd major snow event for UK. It is going to be big snow for SW and S. Also note the 'sudden' increase of warning for heavy snow for SE this weekend. One has to ask why the meto have taken so long to to issue warning????? Some will post unniceties BUT I've been warning for some time for upcoming period and that there will be sudden upgrades in snowfall.

BFTP

Going to be a good week. I think that there is a good chance that you are pretty close on the timing. I actually think that you are about 2 days early, with the 16th being the time where it really gets interesting.

Memories of 63. As Ian said Irresistible force and Immovable object, but remember, where we live, the Atlantic always wins in the end -- although it may be March before that happens :p

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Exeter sticking to their own raw output rather than ECM at t+120 with the low keeping south of the UK:

post-1052-12629909260042_thumb.png

ECM at t+120:

post-1052-12629911082842_thumb.png

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note that the GFS quirk is to overplay the strength of lows. at T78 the low was weaker than projected in 12Z and the heights to the north slightly further West. bin the rest of the run; will change.

Completely agree, that low will get weaker or stall or slide ( or all three). Snow quite early on for some, totally unknown for us after that.

FI? T96 or sooner

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Ian Brown highlighted nicely the plan ahead. As I have said, attemtped breakdown from 12-20 but 14th onwards when fun begins. This will be 3rd major snow event for UK. It is going to be big snow for SW and S. Also note the 'sudden' increase of warning for heavy snow for SE this weekend. One has to ask why the meto have taken so long to to issue warning????? Some will post unniceties BUT I've been warning for some time for upcoming period and that there will be sudden upgrades in snowfall.

BFTP

As someone who has watched winters on netweather now for 6 years BFTP, please don't bat an eyelid at those who may pour scorn on your predictions. Without people like you updating the site on what you believe will happen it would have been a lot poorer for us all.

As we begin to move into the realms of feb are you still looking at a very mild month? The reason I ask is that if this cold spell lasts as long as some think, would the synoptics not seen now for 30 years affect you forecasting methods?

Anyway please keep your thoughts coming it makes everything much more interesting.

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Going to be a good week. I think that there is a good chance that you are pretty close on the timing. I actually think that you are about 2 days early, with the 16th being the time where it really gets interesting.

Memories of 63. As Ian said Irresistible force and Immovable object, but remember, where we live, the Atlantic always wins in the end -- although it may be March before that happens :)

Hi NNW

Yes I prob will get exact timings wrong BUT have to stick with my LRF postings to avoid accusations of adjusting dates to fit the bill :) . Dates are peak energy timings and so notable storms are within. I agree with your assessment.

BFTP

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Ian Brown highlighted nicely the plan ahead. As I have said, attemtped breakdown from 12-20 but 14th onwards when fun begins. This will be 3rd major snow event for UK. It is going to be big snow for SW and S. Also note the 'sudden' increase of warning for heavy snow for SE this weekend. One has to ask why the meto have taken so long to to issue warning????? Some will post unniceties BUT I've been warning for some time for upcoming period and that there will be sudden upgrades in snowfall.

BFTP

Have I missed something, I cannot see any sudden warnings from the MetO, the warnings for this weekend have not change this evening? I do note that the warnings do not match the TV forecasts which suggest the snow will move quite a bit further inland, London is not even in the orange?

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Going to be a good week. I think that there is a good chance that you are pretty close on the timing. I actually think that you are about 2 days early, with the 16th being the time where it really gets interesting.

You say the fun starts on the 16th, but is this a good sign? I know it's a long way out but am I missing something that you haven't: http://www.wetterzentrale.de/pics/Rtavn2161.html. Not negating what you've said at all, I just don't see how that would continue the cold and snowy theme ??

Thanks.

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I can see that low on Tuesday ending up further south and going into France and i wouldn't be suprised if it did but we'll have to wait and see, i think either way another snow event looms for southern and parts of SW England and maybe Central and eastern parts if it gets that far.

But also sorry i have to ask this in this thread but don't know where else to ask.

But in regards to Dry snow, i read somewhere years back that the air temperature has to be 0c for this to happen but i wanted to know what temp does the dew point have to be for this to happen?

Many Thanks.

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i really am struggling to make my mind up on the models atm. for one i am thinking are they still cold enough to keep my snow and cold enough for snow to still fall next week. i just cannot make my mind up if the set up showing next week will help us later on for the rest of the winter.dry.gifdry.gif

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Have I missed something, I cannot see any sudden warnings from the MetO, the warnings for this weekend have not change this evening? I do note that the warnings do not match the TV forecasts which suggest the snow will move quite a bit further inland, London is not even in the orange?

Latest BBC SE News forecast is for HEAVY SNOW for SE Sat night and Sunday. Up to today prolonged light snow was forecast.

BFTP

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Ian Brown highlighted nicely the plan ahead. As I have said, attemtped breakdown from 12-20 but 14th onwards when fun begins. This will be 3rd major snow event for UK. It is going to be big snow for SW and S. Also note the 'sudden' increase of warning for heavy snow for SE this weekend. One has to ask why the meto have taken so long to to issue warning????? Some will post unniceties BUT I've been warning for some time for upcoming period and that there will be sudden upgrades in snowfall.

BFTP

Are You talking about Sunday night? If so isnt the bulk of the PPN over the North of England, GFS now shows most of the PPN over the north not the south east.

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As someone who has watched winters on netweather now for 6 years BFTP, please don't bat an eyelid at those who may pour scorn on your predictions. Without people like you updating the site on what you believe will happen it would have been a lot poorer for us all.

Anyway please keep your thoughts coming it makes everything much more interesting.

Thanks YIDO, no not pour but posts do get lost in the mirth and so hard to recall/prove/show previous posts. I'll stick with it because of the tremendous posters on here,...but thanks bud.

BFTP

Are You talking about Sunday night? If so isnt the bulk of the PPN over the North of England, GFS now shows most of the PPN over the north not the south east.

SE this weekend, SW and S for 14th particulrly onwards.

BFTP

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Hi NNW

Yes I prob will get exact timings wrong BUT have to stick with my LRF postings to avoid accusations of adjusting dates to fit the bill :nonono: . Dates are peak energy timings and so notable storms are within. I agree with your assessment.

BFTP

You are my hero BFTP :) and I treasure every response :) (ive also drunk 2 bottles of wine!)

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You are my hero BFTP :) and I treasure every response :) (ive also drunk 2 bottles of wine!)

LOL....Do not discount tonights 18Z GFS!!!!. One more bottle please...at least :)

RJS may kill me but I am close to giving 'cold' lovers a potential dream Feb forecast....but mid Jan to confirm :nonono:

BFTP

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Would I be right in assuming that if the southern arm of the jet strengthens and further LP's run towards Iberia (as per the posted Fax chart) this cold spell could go on? - as somebody else mentioned it could take another attemp at least from the Atlantic to break the HP and who knows even further snowfall.

In assessment would you say that the chances of the cold spell continuing have increased/DECREASED since this morning?

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Would I be right in assuming that if the southern arm of the jet strengthens and further LP's run towards Iberia (as per the posted Fax chart) this cold spell could go on? - as somebody else mentioned it could take another attemp at least from the Atlantic to break the HP and who knows even further snowfall.

In assessment would you say that the chances of the cold spell continuing have increased/DECREASED since this morning?

They have increased a little since this morning, but also decreased a little since yesterday evening. The GFS suggests the cold spell hanging on in the north (albeit with a slow thaw near east-facing coasts) until into next weekend, but for the southern half of England it turns milder by Thursday. Not sure how far north the milder air would get on the ECM. In contrast the earlier GFS 12Z run had the milder air getting no further than the south coast.

For the cold to continue much beyond next week I think we're going to need some kind of general pressure rise to the north- a retrogression over towards Greenland would be the surest bet (although not supported by the models at this stage). Some runs have suggested that if we do get the high ridging back across to our north it may pull in colder air from the east again, the GFS 12Z, and some of the lesser models, were suggesting -10C 850hPa values returning towards the end of next week with a likely return of the theme of sunshine and snow showers for eastern districts.

But if the high stays out east, while we'll have a battle between mild and cold next week with the boundary between mild and cold airmasses very much up in the air (FI really does start at around T+96 as Nick F rightly said earlier), chances are the Atlantic will get us second time around during the week after.

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LOL....Do not discount tonights 18Z GFS!!!!. One more bottle please...at least drinks.gif

RJS may kill me but I am close to giving 'cold' lovers a potential dream Feb forecast....but mid Jan to confirm cc_confused.gif

BFTP

February is going to be quite difficult to forecast. I know some were going on about a potential stratospheric warming event. As it stands the stratosphere is still below average and is not forecast to go above average for the foreseeable future. It would greatly increase our chances and help sustain northern blocking if we can get some sort of warming event before January is out. If we don't then i think GP will be right with a mild Feb being the most likely with the below average stratosphere removing the -AO and the polar vortex regaining its strength. Will be interesting see what happens smile.gif

http://strat-www.met...t=temps&alert=1

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Latest BBC SE News forecast is for HEAVY SNOW for SE Sat night and Sunday. Up to today prolonged light snow was forecast.

BFTP

I saw earlier on the BBC forecast this snow didn't really make it's way to London and this way. Rob did mention some spells of snow, as you said. However, looking a the charts, to me it looked like it'll be a lot more extensive?

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Hi NNW

Yes I prob will get exact timings wrong BUT have to stick with my LRF postings to avoid accusations of adjusting dates to fit the bill :whistling: . Dates are peak energy timings and so notable storms are within. I agree with your assessment.

BFTP

You know Fred I've never understood your method and I don't mind saying that although I love your posts and admire your enthusiasm I don't rate it either, which I think is fair enough and is no reflection of the work you put into it. The bit I really don't get is this peak energy thing; in particular why it should manifest itself as storms over the tiny landmass that is the UK.

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Just looking at latest gfs pub run... and would like to ask a quick question, mentioned this in the scotland thread and had it suggested i pop it in here for some of our experienced posters to answer:

It shows us 'warming up' to -5 850s and possibly even 0's... then it shows the -5 and colder reappearing from almost nowhere eg no draw off the continent.

Is this because the cold is so embedded over us and with the ground utterly frozen that we can quickly generate our own cold or even cool any southwest stream that may appear?

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