Model Output Discussion - 31/10/2014 and Beyond

[IDO]

I must say that some posters suggesting you can't get cold at this time of year, well ask the USA, they may say differently. This is a rare setup and again the UK has missed the boat. An extended 4-6 days of extreme cold in  the US:

 

  

 

Bearing in mind we are on the same latitude as many S. Canadian cities, if that upper trough had dropped over us it would have put us into -14 or worse uppers.

 

Still lots of differences in the models as to how the pattern develops:

 

Navgem: JMA: 

 

ECM:   GFS: 

 

More runs needed to resolve.

 

 

 

 

[Continental Climate]

Mid November onwards is going to be very interesting if charts like this verify

 

 

Yep that looks very good doesn't it!!! The polar vortex is shredded this year. What i think we are going to see this year is another epic winter in the conus!! Polar vortex v USA round two!!!

[karyo]

this may be relevant but mods please move to winter thread if felt this is the wrong area.

latest ENSO official forecast for winter into spring for the northern hemisphere

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/index.shtml

John, can you tell us what it says? I can't open this link.

[johnholmes]

just copying the main para as to what the ENSO is predicted to be

Similar to last month, most models predict El Niño to develop during October-December 2014 

and to continue into early 2015 (Fig. 6). However, the ongoing lack of clear atmosphere-ocean coupling

and the latest NCEP CFSv2 model forecast (Fig. 7) have reduced confidence that El Niño will fully 

materialize (at least five overlapping consecutive 3-month values of the Niño-3.4 index at or greater than

0.5°C). If El Niño does emerge, the forecaster consensus favors a weak event. In summary, there is a 

58% chance of El Niño during the Northern Hemisphere winter, which is favored to last into the Northern 

Hemisphere spring 2015 (click CPC/IRI consensus forecast for the chance of each outcome.

 

with thanks to cpc.ncep

[PolarWarsaw]

 

just copying the main para as to what the ENSO is predicted to be

Similar to last month, most models predict El Niño to develop during October-December 2014 

and to continue into early 2015 (Fig. 6). However, the ongoing lack of clear atmosphere-ocean coupling

and the latest NCEP CFSv2 model forecast (Fig. 7) have reduced confidence that El Niño will fully 

materialize (at least five overlapping consecutive 3-month values of the Niño-3.4 index at or greater than

0.5°C). If El Niño does emerge, the forecaster consensus favors a weak event. In summary, there is a 

58% chance of El Niño during the Northern Hemisphere winter, which is favored to last into the Northern 

Hemisphere spring 2015 (click CPC/IRI consensus forecast for the chance of each outcome.

 

with thanks to cpc.ncep

 

 

What kind of effect does that have on our winter in laymans terms?

[karyo]

Thanks John. I won't be surprised if this el nino doesn't materialise at all and we remain neutral throughout the winter

.

 

Karyo

[Hocus Pocus]

 

just copying the main para as to what the ENSO is predicted to be

Similar to last month, most models predict El Niño to develop during October-December 2014 

and to continue into early 2015 (Fig. 6). However, the ongoing lack of clear atmosphere-ocean coupling

and the latest NCEP CFSv2 model forecast (Fig. 7) have reduced confidence that El Niño will fully 

materialize (at least five overlapping consecutive 3-month values of the Niño-3.4 index at or greater than

0.5°C). If El Niño does emerge, the forecaster consensus favors a weak event. In summary, there is a 

58% chance of El Niño during the Northern Hemisphere winter, which is favored to last into the Northern 

Hemisphere spring 2015 (click CPC/IRI consensus forecast for the chance of each outcome.

 

with thanks to cpc.ncep

 

This is generally the case when you have a negative PDO, the lack of ocean and atmospheric coupling. Sorry mods off topic.

[Purga]

Lots of cold air accumulating over Canada to power up the jet

Nice blocking over Scandinavia but I fear it won't do us much good.

[Gowon]

What kind of effect does that have on our winter in laymans terms?

 

I think your more likely to get a ssw during nino/nina winters.. Nuetral conditions makes it less likely.

Edited November 6, 2014 by Vivian

[ANYWEATHER]

Its early days folks on the Winter scene ahead. Business as usual in the days ahead with a broad swathes of low pressure systems bringing often rather cold conditions . The FI charts ,yes a silly timescale that far ahead  at T+240 shows a disruptive jetstream  from ecm and gfs , a potential though for cold to filter across the country by then Watch out from Mid Month Onwards.

Edited November 6, 2014 by ANYWEATHER

[Winter Cold]

Its all just a bit confusing for the less knowledgable like me. Ive been listening and learning a lot over the past few weeks, in particular Steve Murrs posts. For example, the last frame of ECM tonight looks to be sucking heights over to Greenland as he suspected would happen, as shown below:

 

 

But then weve had both Ian and snowballz on today, who both work for the Met Office I beleive basicaly saying nothing is showing up, and as we know, they have so much more data.

 

Can even they be caught out and perhaps have to make quick adjustments/changes to their outlooks very quickly?

[snowking]

Lots of cold air accumulating over Canada to power up the jet

Nice blocking over Scandinavia but I fear it won't do us much good.

 

Purga this is not meant to be a dig at all so please don't take it to be, but I am just interested. I have seen you post about this quite a lot during the past couple of days, but I have yet to actually see any sort of powered up jet stream chart to accompany it, only something very weak and not particularly zonal such as this:

 

 

And that's actually one of the stronger frames on offer.

 

I think it is important to bear in mind that the jet stream is generally measured at around 200-300mb, and so in fact whilst we might be seeing the potential for a sharp thermal gradient at 850mb, this is not the be all and end all in terms of how strong the jet stream is. As I said, please do not take this as a personal dig because that is not my intention at all, just that I like to see the physical evidence of what is being suggested coming to fruition what we are seeing right now is not all that different to many other years gone by. Here's 2009 for example:

 

 

I think all in all there is still a heck of a lot of over-reaction going on right now on either side of the equation for the time of year. What we are seeing right now is fairly typically what was to be expected from the best fit analogue years, and indeed from the climatology provided by Cohen et al. Like I said yesterday everyone will be sick and tired of hearing about this, but Scandi High, Aleutian low and most pertinently, troughing centred just to the West of the UK.

 

I also take on board Cloud 10's comments from yesterday regarding last winter too - unfortunately what was expected to develop later in the season got close but not quite close enough for us. It also hopefully goes to show that no forecast nor forecaster is infallible - in fact, very much the opposite! There is absolutely no guarantee that this year my expectations (or indeed the chosen analogue years) will meet reality.

 

Trying to take a balanced view of things right now out to the middle of this month:

 

 

And the key features outlined previously are pretty much what we see, and the implications for the UK? Pretty unsettled mostly, with an alternation of slightly below to slightly above average likely temperature wise.

 

No absolute signs of being sent in to the freezer, no signs of me having to get the shorts out again (ladies of the UK will be thankful I'm sure), and certainly no signs of a rampant jet stream any time soon.

 

Regards,

SK

Edited November 6, 2014 by snowking

[ANYWEATHER]

Its all just a bit confusing for the less knowledgable like me. Ive been listening and learning a lot over the past few weeks, in particular Steve Murrs posts. For example, the last frame of ECM tonight looks to be sucking heights over to Greenland as he suspected would happen, as shown below:

 

 

But then weve had both Ian and snowballz on today, who both work for the Met Office I beleive basicaly saying nothing is showing up, and as we know, they have so much more data.

 

Can even they be caught out and perhaps have to make quick adjustments/changes to their outlooks very quickly?

Steve Murr loves the cold weather and hence has a big attraction from cold loving fans , certainly something to be happy tonight, although big cold will wait a bit!

[Snowman.]

Its all just a bit confusing for the less knowledgable like me. Ive been listening and learning a lot over the past few weeks, in particular Steve Murrs posts. For example, the last frame of ECM tonight looks to be sucking heights over to Greenland as he suspected would happen, as shown below:

 

 

But then weve had both Ian and snowballz on today, who both work for the Met Office I beleive basicaly saying nothing is showing up, and as we know, they have so much more data.

 

Can even they be caught out and perhaps have to make quick adjustments/changes to their outlooks very quickly?

 

Probably because you don't want to tell the nation that something abnormal is popping up.

 

Plus no model is actually showing cold yet just synoptics that can lead to it.

 

 

Wouldn't worry too much.

[nick sussex]

Its all just a bit confusing for the less knowledgable like me. Ive been listening and learning a lot over the past few weeks, in particular Steve Murrs posts. For example, the last frame of ECM tonight looks to be sucking heights over to Greenland as he suspected would happen, as shown below:

 

 

But then weve had both Ian and snowballz on today, who both work for the Met Office I beleive basicaly saying nothing is showing up, and as we know, they have so much more data.

 

Can even they be caught out and perhaps have to make quick adjustments/changes to their outlooks very quickly?

At the moment its a slow burner, the nature of the set up means it will take some time to get the pieces to fit and a lot depends on how much trough disruption occurs, will some of that feed further ese into central Europe?

 

I think we'd be looking at the second half of the month at the earliest with the proviso of course that the NWP modelling of any pressure rises up towards eastern Greenland and Svalbard could be very suspect at this timeframe.

 

It's a difficult set up for the NWP but even if we get some more favourable trough disruption earlier it would still take some time to get the real cold into the UK.

[mcweather]

Its all just a bit confusing for the less knowledgable like me. Ive been listening and learning a lot over the past few weeks, in particular Steve Murrs posts. For example, the last frame of ECM tonight looks to be sucking heights over to Greenland as he suspected would happen, as shown below:

 

 

But then weve had both Ian and snowballz on today, who both work for the Met Office I beleive basicaly saying nothing is showing up, and as we know, they have so much more data.

 

Can even they be caught out and perhaps have to make quick adjustments/changes to their outlooks very quickly?

 

Much though I have immense respect for the Met office and all the work they do, their forte is short to medium term forecasting which is what they are paid mostly to do. They will almost never say anything too exciting about cold and snow until it is nailed on within seven days.

 

Even back in Nov 2010 when this place was going nuts as the ensemble graphs showed temperatures falling  off a cliff the Met office medium range forecasts were worded extremely cautiously in terms of ''possiibly turning colder later in the period with an increased chance of showers turning to snow in the north and east''

 

The experienced members on here could all see what was going to happen but the Met office with a national reputation to protect will always err on the side of caution especially with likes of the Daily express and James Madden willing to snipe at every opportunity.

[Polar Maritime]

Model Output Discussion please.

 

Thanks, PM.

Edited November 6, 2014 by Polar Maritime

[SE Blizzards]

ECM 12z mean day 10 chart. 2014

 

 

ECM 12z mean day 10 chart. 2013

 

 

Just look at the difference of the NH. Staggering.

 

The PV really is struggling this year, there's no doubt about that what so ever.

 

All cold fans deserve a cold and snowy winter after last years mild wet washout, and right now 'we' seem to be heading in the right direction. Patience is required, but maybe 'something special' is brewing.

Edited November 6, 2014 by SE Blizzards

[Captain Shortwave]

We are still probably around 2 weeks at a minimum from a cold spell given the time needed to set up the pattern for cold to head to the UK and of ourse the time needed for it to travel and arrive in the UK.

I must admit though the northern hemisphere charts are looking a lot better for week 2 than they did this morning.

This mornings mean was starting to suggest that Atlantic westerlies were starting to gain the upper hand in the battle between the block to our east and the Atlantic/UK trough.

The day 10s for the GEM and GFS

Also much better to our north with a trend for splitting the tropospheric vortex right over the pole.

Of course the caveat is that in 10 days time, we are still looking at an unsettled picture with low pressure just west of the UK.

[garbagebags]

I must say that some posters suggesting you can't get cold at this time of year, well ask the USA, they may say differently.

 

Couldn't agree more. So many people saying things like stop looking for cold in November, nothing can happen till december, wait till december.

Do people seriously not remember only 4 years ago?

[SMU]

Its all just a bit confusing for the less knowledgable like me. Ive been listening and learning a lot over the past few weeks, in particular Steve Murrs posts. For example, the last frame of ECM tonight looks to be sucking heights over to Greenland as he suspected would happen, as shown below:

 

But then weve had both Ian and snowballz on today, who both work for the Met Office I beleive basicaly saying nothing is showing up, and as we know, they have so much more data.

 

Can even they be caught out and perhaps have to make quick adjustments/changes to their outlooks very quickly?

Its all just a bit confusing for the less knowledgable like me. Ive been listening and learning a lot over the past few weeks, in particular Steve Murrs posts. For example, the last frame of ECM tonight looks to be sucking heights over to Greenland as he suspected would happen, as

 

But then weve had both Ian and snowballz on today, who both work for the Met Office I beleive basicaly saying nothing is showing up, and as we know, they have so much more data.

 

Can even they be caught out and perhaps have to make quick adjustments/changes to their outlooks very quickly?

Evening Winter Cold -

Welcome to the forum let me answer your post -

You will very rarely a forecast past 7 days (144) from the met office - generally up until that point all the focus is on the short to medium term for public viewing -

Also you will never see any met office employee post on here & go against the consensus data -

That being the mogreps / UKmet ensembles & ECM

Today the consensus was nothing close to what I posted around the sharp pressure rise around greenland.

What I put together is what I expect to happen based on understanding the model bias & weaknesses that I have observed since 2001 when the GFS was the AVN.

What may change tonight is there interest in patterns past day 9, of course it wont be aired on here or in public however it will certainly prevoke interest.

Unfortuntely its unlikely you will see it here....

[bluearmy]

So far this month, the sceuro block has been stuck well to our se, preventing the disrupting Atlantic troughing from making headway across into Europe to our south. Extended ens (naefs and ECM) have shown little appetite to change this. The 12z ECM ens at day 10 anomaly is showing the trough getting well into Europe which will advect a mean soueaster across us. Should get a view on the extended shortly to see if this is backed up out to day 15, the day 10 850 spreads get the cold as far as Eastern Europe and east scandi

[Summer Sun]

At this stage the GFS ens keeps the 850's above average from around Tuesday till the end of its run, so temperatures would probably be ranging from average to slightly above average though feeling colder in any spells of wet and windy weather

 

[Man With Beard]

Mid November onwards is going to be very interesting if charts like this verify

There are clearly two approaches in this thread right now. One is focussing on the here and now - let's not pretend, it is Atlantic dominated, blocking is locked over Eastern Europe meaning we are the destination for Atlantic lows, and so rain is certainly a concern for the next 10 days. Let's not pretend either - there's no concrete evidence that this pattern is going end in reliable time frames (day 7 or nearer).

The other approach is the long term, hemispheric one. It involves looking at what is happening thousands of miles away, even other sides of the world. It is clear that events on the NH as a whole are not typical of a zonal westerly winter. The picture now suggests that even though the Atlantic is dominating right now, the conditions exist, fairly easily, for this to change by blocking shifting around the hemisphere, perhaps to Greenland, shifting wind patterns and eventually allowing weather to get to us from a non-Atlantic destination. BUT - when things are coming from thousands of miles away with no help from the jet stream, you are talking at least an extra week beyond the reliable timeframe, and models simply aren't going to firm up on any ideas until a lot nearer the time. You won't get a professional, commercial forecast if the details are big picture only and are sketchy on local detail.

It's always useful to distinguish between the two ways of looking at things.

Edited November 6, 2014 by rjbw

[ItNeverSnowsInWindsor]

I think the next 12 hours could be crucial in terms of model output to decide whether there's momentum towards a build of pressure towards Greenland which have been hinted by developments in the Wave 1.