Model Output Discussion - 30th November onwards

[forecaster]

Why!?!?!!?!?!?!?!?!!     lol.

 

I know. Sorry. It doesn't help that this years' upcoming easterly on the ECMWF det is progged for close to the same date!

[SW Saltire]

Afternoon. Todays metoffice updates suggest to me low presure to the northwest with a euro high lingering over the South east and near continent. Not one word sugesting any consideration of todays 00:00 ECM.

Realistically, they are hardly going to call a Scandi high when ensemble support is at best 50/50 for it and when it is well over a week away. Can you imagine if they had run with the northerly when (i think it was 2 mornings ago) we almost had agreement on a much more severe spell. The MetO did mention the 'beast from the East' for that easterly last year, i remember my neighbour saying that to me as i had just had to endure the set of 12z that totally crushed our dreams... 

[Gavin Hannah]

GFS 06z finishes with the beginnings of an Eastern promise. The 00z and 06z share similar evolutions through much of the runs, with varying degrees of differences post cold shot this thur/fri. HP looks set to be in and around Europe as we approach Xmas going on trends. the position of said HP however will determine whether we get a green or white xmas.

 

The ECM has a lovely Scandi ridge by 240 which (if it came off) would send this community into meltdown at t-minus 24 hours.

 

I can honestly say compared to last year, this is quite exciting. Last December was an Atlantic rinse repeat situation on the models. This year however, is far more exciting to watch and far less predictable.

Edited December 2, 2013 by IBTHToThoseShortwaves

[nick sussex]

Here is the aforementioned ECM output and a good example of how important upstream events are to the UK in terms of getting colder weather:

 

 

That was the ECM 00hrs output for 120hrs on 6 December 2012, note the sharpness ahead of the upstream low and the shape of the low to its east.

 

Now the ECM for two days later the 00hrs run on the 8th:

 

 

You can see there both lows less amplified and the misery shortwave energy to the north of Norway, if the shortwave had appeared but we still saw that sharpness upstream then enough energy would have headed se to sustain a ridge to the north, maybe not the bitterly cold of the original easterly but still cold and a chance things could have developed a bit more interesting afterwards.

 

Interestingly it was the much maligned GFS 18hrs run that started throwing in that shortwave spoiler to the north of Norway, and was the initial harbinger of doom!

Edited December 2, 2013 by nick sussex

[SW Saltire]

GFS 06z finishes with the beginnings of an Eastern promise. The 00z and 06z share similar evolutions through much of the runs, with varying degrees of differences post cold shot this thur/fri. HP looks set to be in and around Europe as we approach Xmas going on trends. the position of said HP however will determine whether we get a green or white xmas.

 

The ECM has a lovely Scandi ridge by 240 which (if it came off) would send this community into meltdown and t minus 24 hours.

 

I can honestly say compared to last year, this is quite exciting. Last December was an Atlantic rinse repeat situation on the models. This year however, is far more exciting to watch and far less predictable.

Exactly, unlike winters of circa 10 years ago we are not sitting here in February, still snowless and looking at week two for inspiration. This is only the second day of winter proper, with a northerly blast imminent and the rumblings of a more substantial cold spell a possibility. I wonder how long this optimism will last... probably until the next t72 shortwave spoiler! 

[nick sussex]

I do sometimes question my own and others obsession with easterlies. They often disappoint even if they make it to T0, you never know what you'll get, that awful murky easterly with snow grains, or a more drier se based flow, if you're very lucky you get the 5 star easterly with heavy snow showers driven in on a biting wind. They take an age to get agreed on in the models and often implode.

 

If they're part of the lovely retrogression type with Greenland block and rinse and repeat much like the Dec 2010 pattern, indeed then the easterlies disappointed because the models were slow to retrogress the pattern but at least you knew that even if the snow showers window was short you'd have a northerly to look forward to and not one that was gone in the blink of an eye like most northerlies we see without Greenland blocking.

 

But yet for some reason I just can't resist obsessing over them! At the moment realistically given the upstream pattern and where the PV is expected to set up then the only way to get some real cold into the UK is from the east or ne, any other route really does require a team of Hollywood script writers.The trend for troughing in the mid Atlantic is there across all the outputs, we'll have to see over the next few days whether the Scandi high trend develops further.

[Gavin Hannah]

 

But yet for some reason I just can't resist obsessing over them! At the moment realistically given the upstream pattern and where the PV is expected to set up then the only way to get some real cold into the UK is from the east or ne, any other route really does require a team of Hollywood script writers.The trend for troughing in the mid Atlantic is there across all the outputs, we'll have to see over the next few days whether the Scandi high trend develops further.

 

If only we could get a super block set up stretching from Greenland heading east and then stretching south west from central Siberia, with the UK directly in the firing line....... 

[SW Saltire]

I do sometimes question my own and others obsession with easterlies. They often disappoint even if they make it to T0, you never know what you'll get, that awful murky easterly with snow grains, or a more drier se based flow, if you're very lucky you get the 5 star easterly with heavy snow showers driven in on a biting wind. They take an age to get agreed on in the models and often implode.

 

If they're part of the lovely retrogression type with Greenland block and rinse and repeat much like the Dec 2010 pattern, indeed then the easterlies disappointed because the models were slow to retrogress the pattern but at least you knew that even if the snow showers window was short you'd have a northerly to look forward to and not one that was gone in the blink of an eye like most northerlies we see without Greenland blocking.

 

But yet for some reason I just can't resist obsessing over them! At the moment realistically given the upstream pattern and where the PV is expected to set up then the only way to get some real cold into the UK is from the east or ne, any other route really does require a team of Hollywood script writers.The trend for troughing in the mid Atlantic is there across all the outputs, we'll have to see over the next few days whether the Scandi high trend develops further.

Well, surely IMBYism comes into play. Most people on this forum are English and most of those are southern centric, therefore Scotland would have to be buried in snow in order for Portsmouth to get a dusting from a northerly 9/10. Thus, those in the South-east will obviously prefer the easterly. Not only are you looking at a less reliable way of getting cold into the UK than a northerly with a Greenland block but you have now got a greater audience all intently waiting for the next frame. Resulting, - as you so aptly put- in casualties with a lot more than toys and prams being thrown in this forum  

Edited December 2, 2013 by SW Saltire

[Frosty.]

We need to take care tonight & tomorrow morning peeps because some thick fog is likely to form across the southern half of the uk with a slight frost, the fog could be reluctant to clear from some areas tomorrow and where that occurs, max temps will struggle to get much above freezing, so, it could be close to an ice day tomorrow in parts of the south. A band of rain spreading across the far north tonight but pushing further southeast tomorrow across the rest of scotland but fragmenting in the process, becoming windier, brighter and colder across the far north during tomorrow with sunny spells and a few fast moving showers. Wednesday looks cold across the northern half of scotland with frequent wintry showers and westerly gales, further south, less cold with a lot of cloud and patchy rain..the BIG change arrives on thursday with an active cold front swinging southeast across the uk and to the north of it, the arctic winds will be digging in with frequent snow showers becoming heavier across the far north with drifting in the strengthening Arctic airflow, gales and disruptive snow for the top end of the BI on thurs / fri.........brighter further south with scattered wintry showers and sharp frosts but feeling sub zero in the strong winds which will accentuate the cold during friday and into saturday before winds ease and back westerly.

[cheshire snow]

Just like to point out that whilst the focus for snow seems to be in Scotland,There is also a strong possibility for snow showers

through the Cheshire gap towards the N Middlands Late Thursday/ early Friday.

 

C.S

[AWD]

Personally i think the signal for pressure to build to the E/NE of the UK is relatively notable this morning across all model suites.

As others have said, the low res GFS Op is givinh reptative hints of this scenario lately along with the EC Op.

The likelihood is however, that the 0z EC Op was too progressive with the pattern, therefore a slower progression is likely. Don't be suprised then if future EC Ops dont bring this forward for a while or indeed, variates with the pattern in FI.

The EC ens, as posted above, show a split, with approx 50% going for blocking to our NE vice a W/SW source. However again, less progressive than the Op, with the key timeframe being 13th - 16th Dec.

The GEFS/GEM/NAEFS also all hint at some sort of build of pressure to our E/NE in the longer term. (Image courtesy of Matt Hugo);

So interesting potential in the longer term, something to keep us all talking if nothing else. Whilst the signal for a pressure build over Scandi is relatively notable, the degree of advection of cold, if any is worthless at such a range. The build of pressure is just the foundation of getting any easterly into the UK. Getting cold from it is another matter.

[nick sussex]

If only we could get a super block set up stretching from Greenland heading east and then stretching south west from central Siberia, with the UK directly in the firing line....... 

Lol! actually bigger isn't always better! Do you remember the bitter cold spell that effected mainland Europe in February 2012, it did effect the UK but not as greatly, that had that super large high extending all the way from Siberia, the problem is for the UK that its always on the last stop west for easterlies, in a sense that high was too big for its boots.

 

For example which do you think gave the better conditions in terms of snow and cold?

 

 

 

Its better IMO to have the smaller high with the centre closer to Scandi and the PV dropping south into western Russia, than that huge high centred further to the east.

[Ian Brown]

Just like to point out that whilst the focus for snow seems to be in Scotland,There is also a strong possibility for snow showers

through the Cheshire gap towards the N Middlands Late Thursday/ early Friday.

 

C.S

 

There is very little possibility CS, the Northerly is a 'clipper' with pressure too high in Western areas and with the flow cut off too soon to get the Cheshire gap band going.

[garbagebags]

This entire page, all talk about a potential easterly out in FI. And nothing on the mid term - very cold northerly,Why do people do this?

 

-the previous page

Edited December 2, 2013 by garbagebags

[stratty]

This entire page, all talk about a potential easterly out in FI. And nothing on the mid term - very cold northerly,Why do people do this?

 

-the previous page

 

....because they can?! The northerly for most is going to be pretty much non-eventful for most by the looks of it, so what happens after could be more exciting........Who knows? (i think i heard that recently!)

Edited December 2, 2013 by stratty

[andymusic]

This entire page, all talk about a potential easterly out in FI. And nothing on the mid term - very cold northerly,Why do people do this?

 

-the previous page

 

S'pose we're all trying to see as far ahead as possible to suss out the next trend/weather possibility - like chess - once something has been settled/nearly settled - the challenge is over!

[garbagebags]

....because they can?! The northerly for most is going to be pretty much non-eventful for most by the looks of it, so what happens after could be more exciting........Who knows? (i think i heard that recently!)

 

Well I've just looked and I don't see an easterly, not even in FI. Maybe, just maybe, the slightest hints of it heading possibly that way maybe, in the very last frame of FI...Hardly even worth talking about. I just always see the same. People obsessed with easterlies / FI and not about the next "real" event. 

[SW Saltire]

Well I've just looked and I don't see an easterly, not even in FI. Maybe, just maybe, the slightest hints of it heading possibly that way maybe, in the very last frame of FI...Hardly even worth talking about. I just always see the same. People obsessed with easterlies / FI and not about the next "real" event. 

I think the northerly has been well documented, did you think the last forum got to 147 pages by talking about mild south-westerlies? Our weather even just after the weekend is going to be dependent on where that high sets up and thus it is relevant if the high migrates to the north-east and creates the prospect of an easterly 

[Never snows where i live]

Quick question

What is it with this high pressure over the uk?

[lorenzo]

This entire page, all talk about a potential easterly out in FI. And nothing on the mid term - very cold northerly,Why do people do this?

 

-the previous page

 

What Northerly ? Could be a valid question to ask when comparing the amazing output from the 00z runs on Sunday morning and now looking at the way events are unfolding, through last night 12z and this morning. The main areas affected are certainly being discussed in the Regional thread.

 

With the model thread catering for the whole of the country, it is logical for folks to look at the potential set up for the rest of the month, I am sure if this Northerly had remained undiluted then it would still be getting the discussion it deserves. 

 

Plus, it just wouldn't be Winter on the model discussion without our annual hunt for an easterly. It's some kind of weird exorcism and catharthis of last years demons created by the ECM.

[garbagebags]

S'pose we're all trying to see as far ahead as possible to suss out the next trend/weather possibility - like chess - once something has been settled/nearly settled - the challenge is over!

 

Just strange because the coming Northerly is far from "set" It could upgrade, downgrade, last, not last, it could even go the way of "that ECM" and dissapear. Would just be nice to have more model chat with "weather that's likely" rather than "weather that's liked".

[TSNWK]

Realistically, they are hardly going to call a Scandi high when ensemble support is at best 50/50 for it and when it is well over a week away. Can you imagine if they had run with the northerly when (i think it was 2 mornings ago) we almost had agreement on a much more severe spell. The MetO did mention the 'beast from the East' for that easterly last year, i remember my neighbour saying that to me as i had just had to endure the set of 12z that totally crushed our dreams... 

Thank you for the reply. The ensemble support of 50/50 is what we see, if the Met-Office were only seeing the same then I think at the very least there would be words along the lines " later on in the period there are no clear indications " blah blah. They have done that in the past, todays update is short and sweet with no wriggle room with no indication what so ever that the Met-office are considering the Scandi High option.

Edited December 2, 2013 by TSNWK

[UV-RAY]

What Northerly ? Could be a valid question to ask when comparing the amazing output from the 00z runs on Sunday morning and now looking at the way events are unfolding, through last night 12z and this morning. The main areas affected are certainly being discussed in the Regional thread.

 

With the model thread catering for the whole of the country, it is logical for folks to look at the potential set up for the rest of the month, I am sure if this Northerly had remained undiluted then it would still be getting the discussion it deserves. 

 

Plus, it just wouldn't be Winter on the model discussion without our annual hunt for an easterly. It's some kind of weird exorcism and catharthis of last years demons created by the ECM.

Well lets hope that if one does materialise it actually backs up far enough West to deliver for the whole UK and not just the usual suspects. I'm still looking forward to this so called non event this weekend, there's still an outside chance of some snow on Thursday evening and Friday morning for NW England, with a cold weekend to boot with sub zero temps at night and temp crawling just above during the day.

[SW Saltire]

Thank you for the reply. The ensemble support of 50/50 is what we see, if the Met-Office were only seeing the same then I think at the very least there would be words along the lines " later on in the period there are no clear indications " blah blah. They have done that in the past, todays update is short and sweet with no wriggle room with no indication what so ever that the Met-office are considering the Scandi High option.

your welcome, I take your point that Mogreps may not have such a strong signal and thus maybe they do not mention it. However, the MetO word forecasts do change at the drop of a hat and if the Scandi high does make it from distant FI to a closer timeframe on different models then i'm sure they'll mention it. As Ian F has mentioned previously, their attention will be on the more immediate future with weather forums such as ourselves already on to the next cold horizon 

[karlos1983]

Just strange because the coming Northerly is far from "set" It could upgrade, downgrade, last, not last, it could even go the way of "that ECM" and dissapear. Would just be nice to have more model chat with "weather that's likely" rather than "weather that's liked".

 

It has been discussed at length in the past few days, It has upgraded and indeed downgraded with almost every run. Now we are in the more reliable time frame, most agree now that it will just be a quick blast, then after the potential of an Easterly. I'm sure the Regional for your area will be busy with anticipation, but for most, its a case of eyes down and where do we go from her? South westerlies or the hunt for the golden Easterly. Even if the Easterly verifies down to the reliable time frame, we will allbe looking ahead to see how prolonged it may or may not be. That does generally tend to be how it goes in the Mod discussion thread, especially as the Models (GFS) roll all the way out to +384.