Model Output Discussion; into 2015

[Kentspur]

The thing about a good greenland/scandi high in February is unless there is a fair amount of cloud cover in the following days and uppers are low enough from mid February and especially into march the snow down south just seems to dissappear all too quickly.

I've always been more of a December- early Feb cold and snow fan. Though it is just typical that we always seem to see more of these patterns occurring nearer March than around this time of the year

If it happens and it may well be to little to late!.

Couple that with the vortex having a rest recently from wave activity allowing it to regenerate to some degree as we can see from all the models.

Let's add another talking point that a lot of more experienced strat posters feel that this may not benefit us in the uk.

The ecm throws a surge of higher uppers into the uk and deep into eastern northeastern Europe.

Cool wet windy with snow on the Welsh mountains and maybe at lower levels further north especially Scotland but even here boarder line as uppers are not as cold as recent event.

Gfs shows possible topplers as weather systems pass threw which would benefit northern and eastern areas if cold snap is wanted.

Tick tock though the winter pendulum swings further away from anything seen in better winters like 2010.

The strat influence is not a certainty neither is the influence of the Arctic heights mjo still in unfavourable area add strong northern arm of the jet plus a resilient polar vortex as like last year the vortex is underestimated.

Those hoping for a Greenland block might be worth waiting for February as this is a month when blocking can make inroads to Greenland as the zonal train relaxes its grip although this to is not a given.

The uk is about to really head towards a true zonal west to east pattern and it's likely to hold on for a fair amount of time.

Edited December 29, 2014 by Kentspur

[BlueHedgehog074]

In general, the NOAA 8 to 14 day anomaly chart, and the ECMWF/GFS 8 to 10 Day Mean charts do certainly seem to illustrate a rather strong Westerly flow for the British Isles. The fairly tight contour lines (the green line on the NOAA chart and the blue/dark green/black lines on the 8 to 10 day mean) suggest quite a wild Atlantic set up with the Westerly 500mb flow stretching from Eastern America all the way towards Scandinavia. It's possible there could be some ridging to the East of the UK with the 8 to 10 day mean chart from the ECMWF/GFS showing a slight bump in the 500mb flow over Western Europe.  

 

Moreover, some of the rather Low height anomalies to the North or North-West of the UK on the anomaly charts (with the GFS 8 to 10 day mean being particularly notable for this (chart to right), could mean some deep Lows, especially at the 500mb level, being dominant towards North-Western UK. 

 

The anomaly charts seem to be in general agreement for a ridge from the Pacific area, accompanied by the higher than average heights over North-Western America, to try and poke towards Greenland, which may force Lows in the Atlantic to try and take a slightly more Southerly track at times. Otherwise, the worst of the cyclonic conditions generally seems to be towards North-Western UK. 

 

(To Left: NOAA 8 to 14 Day 500mb anomaly chart. To right: ECMWF and GFS 8 to 10 Day Mean/Anomaly Chart)

 

So would agree that, while the weather around 8 to 14 days away is always up for changes, it does seem, for now, that the UK could undergo a spell of Atlantic Westerly drivern weather with some very windy periods, especially towards the North-West. Lows mostly to the North-West or North. Higher Pressure to the South or South-East. The Southern areas, of which, would probably see a little more in the way of settled weather. Nothing particularly cold (though with the usual case of Northern areas being most exposed to cool/chilly Polar Maritime flows and the areas most at risk seeing wintry weather). And nothing particularly mild either, with a mix of cooler and less-cool Westerly flows seemingly looking apparent. 

Edited December 29, 2014 by DiagonalRedLine

[IDO]

Looks straight forward to me this 

http://www.wetterzentrale.de/pics/MT8_Manchester_ens.png

 

Nothing guaranteed after Friday.

 

I do not see much there that would suggest any uncertainty as far as D10, even up to D15. The sine wave of each member just suggests timing issues re the trough/ridge combo. I would argue that the upcoming pattern has strong chances of verifying.

 

  fergieweather

W COUNTRY CONT'D... for a westerly-dominated & effectively milder/unsettled/at times windy regime to dominate at least into next 10-15 days

29/12/2014 11:15

 

  WSI_EuroEnergy

Confidence is high with regards to the general pattern through the 11-15 day. Wet, windy and around average temps. http://t.co/la0gUCkmzk

29/12/2014 14:58

Edited December 29, 2014 by i'm dreaming of...

[Mucka]

Nothing in the output this morning to suggest anything but wet and windy weather being the predominant type through the first half of January.

Any ridge that is built is quickly swept away by a dominant PV (which considering it is in a weakened state shows just how difficult it is to get blocking to take hold at higher latitudes across the Atlantic in Winter)

Only the UKMO gives even a spark of hope of any ridge being strong enough to deflect the jet South in a meaningful way but it is pretty much on its own and will likely backtrack this evening.

 

With zonal conditions looking pretty much locked in for first half of Jan (according tot he output, not necessarily my opinion) it looks as though we will have to hope the strat warming can herald a pattern change second half of Jan.

As people have noted, any chance of true winter cold and blocking have been postponed again so quite frustrating for coldies but depending on the track of these low pressure systems there may be occasional interest in the chance of some transient snow, especially further North.

 

This is a fairly typical UK winter in all honesty and if it sticks to form we will see at least one cold outbreak later in winter and though early hopes of a classic cold winter seems to have been misplaced a couple of cold snowy weeks later would change perceptions greatly of how the winter was on the whole.

Edited December 29, 2014 by Mucka

[IDO]

And if one likes cold & snow the worrying part of Fergie's update is "at least"

 

Yes with the Alaskan Ridge developing again in FI this could be a repeating pattern; November 10th, upcoming and D15 again. This has proved unfavourable for the UK and a boon for cold for the US. Not the same as last winter, but despite the likelihood (thankfully) of less flooding, it is effectively a winter killer like last year. The UKMO picked up this background signal for this winter so no surprise. My thoughts have not changed, we need an SSW to have any chance of prolonged cold/snow.

 

We should know a lot more re the current strat warming and the chances of a SSW early January by the weekend. A reset of the current status quo is needed.

[Penrith Snow]

Great consistency across all the models today, shame they are not this consistent when predicting cold!

The pattern isn't as wet and stormy as last year but snow chances are just as poor so to be honest their isn't much difference.

Wet and 7c is no snowier than wet and 11c!

Andy

[Thunder Snow]

Since there's very little in the way of any decent cold weather on the horizon for the next few weeks (it would seem), my attention is now being drawn to some of the extreme wind speeds that the GFS has been churning out run after run post 192 over the past 4 or 5 days. 

 

To kick off the GFS Op for Thursday afternoon +81 shows a large part of Northen England and Scotland with Max gusts of up to 70 Mph

 

 

WAY in FI but run after run, the 6-11th Jan shows some really stormy outputs, this one the GFS Op for the 9th, showing a system that runs across the SE of the UK, IF this came off as shown then it's batten down the hatches time.

The same ''Storm'' exiting the UK

Sticking with the OP, and the output showing a windy day for everyone on the 11th Jan...

 

That's JUST the Op run, let's delve into the Parallel to see if there's ANY support or if any of the dates coincide..

 

No surprise to see Thursdays wind speeds there, but slightly further south and not quite as strong as the Op, still Max gusts 65 Mph are not to be sniffed at and covering a large area of the UK...

 

.

 

 

The Parallel wants things to get quite windy on Saturday too, getting close to 60 Mph across the South. 

The Parallel then has a small part of NW Scotland getting absolutely battered on Monday the 5th, although they're used to it up there

Just 2 days later and on the 6th Jan the Parallel has almost every part of the UK experiencing wind gusts of between 50-75 Mph 

THE VERY NEXT DAY...7TH JAN !

10TH Jan.again on the Parallel....

 

 

The Parallel is one of the stormiest runs I have ever seen with day after day after day of extremely high winds and presumably copious amounts of rainfall. 

 

FINALLY, looking at the control run for a 3rd and final comparison , looking solely at the pressure charts fr the periods 7-11th Jan...

 

Here's the 7th Jan, looking pretty windy to me

and the 10th Jan again looks very stormy

 

If it wasn't the fact that this is about the 5th or 6th day in a row that the time period 6-11th January is showing up as very stormy on the GFS runs, I wouldn't have bothered posting these charts, but if the trend starts to firm up over the next 7 days then IMO the wind and rain will be getting the headlines and the cold will be taken off people's minds for a short while at least

Nice set of charts for the 10 year anniversary of the Carlisle floods :/

[Eugene]

We have seen this before, the models showing frequent incursions of polar maritime air with wintriness even at lower levels but as we approach the T0, those incursions move further and further norts and in the end we end up with average or even mild weather. This is because the models have the tendency to overdo the extend of those incursions. 

 

Like other posters have already said, tropospherically, there is nothing promising in the models today. 

 

Like the mild weather we've been suffering since Boxing Day. :smiliz19:

[Frosty.]

I remember the last time stormy winds were forecast by the models..erm last week I think it was and there were no wind storms, it was about the time the mo didn't mention any risk of snow and the eventual result was snow and no wind to speak of although things do look rather different this time.

Edited December 29, 2014 by Frosty.

[blizzard81]

Yes with the Alaskan Ridge developing again in FI this could be a repeating pattern; November 10th, upcoming and D15 again. This has proved unfavourable for the UK and a boon for cold for the US. Not the same as last winter, but despite the likelihood (thankfully) of less flooding, it is effectively a winter killer like last year. The UKMO picked up this background signal for this winter so no surprise. My thoughts have not changed, we need an SSW to have any chance of prolonged cold/snow.

 

We should know a lot more re the current strat warming and the chances of a SSW early January by the weekend. A reset of the current status quo is needed.

I must admit, the Meto have been pretty much bang on so far this winter. I remember Fergie quoting the mogreps/glosea models

findings back in early Dec for the xmas period. He stated a waning of the westerly influence, implying anticyclonic conditions around

the xmas period. This has come to fruition, period. The meto have really gone up in my estimations these last couple of years and imo are

second to none. Not much to be proud of in this country at the moment but the meto buck this trend at present.

[TwisterGirl81]

I remember the last time stormy winds were forecast by the models..erm last week I think it was and there were no wind storms, it was about the time the mo didn't mention any risk of snow and the eventual result was snow and no wind to speak of although things do look rather different this time.

 

Really?  Because the wind was very very strong here in Exeter/Devon, we had gusts nearly reaching 60mph a few days ago! 

[fergieweather]

I must admit, the Meto have been pretty much bang on so far this winter. I remember Fergie quoting the mogreps/glosea models

findings back in early Dec for the xmas period. He stated a waning of the westerly influence, implying anticyclonic conditions around

the xmas period. This has come to fruition, period. The meto have really gone up in my estimations these last couple of years and imo are

second to none. Not much to be proud of in this country at the moment but the meto buck this trend at present.

 

I think a problem is often one whereby some people (public) have unrealistically high expectations re the level of detail / confidence that can be attributed to any one month through the winter period. The probabilistic approach used thus far by UKMO through December has been essentially good; however the signal hereforth is ultimately much more tricky (i.e. later this month), as was discussed in the most recent public website update via GloSea (used as principal tool in the pre-Christmas contingency planning notes put together 18 Dec, which called for near-average to below average Jan conditions):

 

"For January, there is a reasonably strong signal, from several models, for the strong

positive North Atlantic Oscillation (NAO) phase, which has dominated the winter

so far, to wane. This weakening of the westerly winds across the Atlantic leads to

an increased chance of cold, blocking patterns developing across northwestern

Europe, compared to earlier in the winter. However, this does not mean that a

prolonged spell of cold weather is necessarily expected in the UK; indeed looking

at the left hand curve in figure T2, there is only a slight shift to colder than average

conditions and the chance of a severe spell of cold weather is similar to

climatology.

For January-February-March as a whole, computer models begin to diverge;

consequently no clear signals emerge and predictability is considered low.

Additionally, apart from the QBO, most external forcing factors are weak. Overall,

while there is no strong signal for cold weather, there is also little evidence to

suggest a very mild season, as experienced last year. The right hand curve in figure

T2 reflects this, being similar to climatology. Nevertheless, short spells of cold

weather are still possible, with current predictions suggesting these are more likely

to occur than last year."

 

The public website 16-30d forecasts from today onwards will become the lead point for further updates to this broad set of expectations.

Edited December 29, 2014 by fergieweather

[MR EXTREMES]

Really? Because the wind was very very strong here in Exeter/Devon, we had gusts nearly reaching 60mph a few days ago!

Yeah agree to be fair it was windy here in the south not extreme windy never the less.

Frosty to be fair fella there really is nothing for coldies to be excited about I'm one myself and I've packed my sledge away but I'm still going to hang on in the hope that the phantom strat warming does happen and that it's not a garden path moment or a early April fools.

But I have very little confidence in anything cold in the next two weeks at least might get shot down here but January as a whole.

I've explained why and I'm sure there are plenty of arguments to counter what my ideas are and I'm fine with that if anyone can show me hard evidence of actual real cold spell I'd be very happy to drag the sledge from the shed.

January weather is a month that provides messy unstable patterns normally so this jan is looking the same but agree it's impossible to right off jan but my ideas suggest this and this is because of the cross model agreement add on the met office stance then there's little hope.

If February the tide turns then we can rejoice and also except that even if four weeks late the cold heart of winter did happen and I truly hope it does if it don't just another year to learn what happened.

Edited December 29, 2014 by emotional rollercoaster

[Frosty.]

Really? Because the wind was very very strong here in Exeter/Devon, we had gusts nearly reaching 60mph a few days ago!

Really? well considering there were supposed to be nationwide gales, they ended up much less of a deal. Just looking ahead, there is a risk of something colder and more settled by the end of January but confidence is low. In the meantime we will have mild wet and windy spells interspersed with colder showery conditions with snow on hills and night frosts during quieter intervals..so really it's the same as we started winter with for the foreseeable future. Edited December 29, 2014 by Frosty.

[Stormyking]

Thursday looking rather unsettled across the UK by the looks of it, with some fairly gusty winds too

 

 

 

GFS P: has the isobars more tighter by the looks of it

[blizzard81]

Yeah agree to be fair it was windy here in the south not extreme windy never the less.

Frosty to be fair fella there really is nothing for coldies to be excited about I'm one myself and I've packed my sledge away but I'm still going to hang on in the hope that the phantom strat warming does happen and that it's not a garden path moment or a early April fools.

But I have very little confidence in anything cold in the next two weeks at least might get shot down here but January as a whole.

I've explained why and I'm sure there are plenty of arguments to counter what my ideas are and I'm fine with that if anyone can show me hard evidence of actual real cold spell I'd be very happy to drag the sledge from the shed.

January weather is a month that provides messy unstable patterns normally so this jan is looking the same but agree it's impossible to right off jan but my ideas suggest this and this is because of the cross model agreement add on the met office stance then there's little hope.

If February the tide turns then we can rejoice and also except that even if four weeks late the cold heart of winter did happen and I truly hope it does if it don't just another year to learn what happened.

Absolutely, and for once I am going to be very blunt and direct here. To argue anything other than the words in your post is to totally

mislead people on this forum. I, like most people on here am a coldie but I am also a realist. All the models today and for last 24 hours

have written off the first half of Jan for true cold - That is what the models are showing and that is what we do - we report what the models are showing!

Some members on here may be regarded as enthusiastic with regards to cold but there is a fine line between enthusiasm and denial.

Edited December 29, 2014 by blizzard81

[steveinsussex]

I remember the last time stormy winds were forecast by the models..erm last week I think it was and there were no wind storms, it was about the time the mo didn't mention any risk of snow and the eventual result was snow and no wind to speak of although things do look rather different this time.

 

It was very windy down south

[The Eagle]

Fairly significant difference for us at 96 on UKM vs GFS re this area of LP in the mid Atlantic.

 

 

 

Edited December 29, 2014 by The Eagle

[mountain shadow]

So. its the 20 to 5 club in here again as we search deepest FI for a smidgen of hope that the strat warming begins to impact on the outer reaches of the model output.

Until then, zonal until around mid January.

[Mr Frost]

Brilliant update Ian - many thanks for that.

Hopefully every single member reads that and takes the information in rather than posting stuff about incoming blizzards or writing off a whole month of Winter.

Naughty short spells of cold weather being more likely than last year is music to coldies ears - a more traditional Winter ahead then hopefully for all the UK and Ireland.

The charts are showing that at the minute - mild days, cold days, cool days and severe gales. Something for everyone!

Let's have a more positive attitude when posting in this thread going forward but still retain realism of course, (whether you prefer cold or mild - we are all weather enthusiasts at the end of the day)

Makes for a better read and a more welcoming thread for all to enjoy.

Cheers

[mountain shadow]

Fairly significant difference for us at 96 on UKM vs GFS re this area of LP in the mid Atlantic.

 

 

 

Why? Looks flat zonal on both.

[Stormyking]

Fairly significant difference for us at 96 on UKM vs GFS re this area of LP in the mid Atlantic.

 

 

 

 

Even bigger difference on the GFS p, much much stronger low coming in!

 

[johnholmes]

For the new folk, obviously a bit confused I would imagine, two posts, neither with charts to explain their differing views on the model outputs.

All I can suggest, I do it regularly is be patient as you gather a feeling for which poster to follow, and in the meantime try this, like I suggested last night, at least for temperature values.

Go to the charts and forecast located at the top of the Net Weather page, run the GFS model and get the temperature section to show and see what that model is actually predicting say 12 or 15Z each day for your area. Compare that to the long term average for your area for early January which you can find on the Met O website. Then make your own minds up if that sounds cold or mild.

It will also help you fairly quickly gain an understanding of the models, say GFS as that is the one most widely used with its 4 runs each day. To help you along visit the Net Wx Guides and have a browse at anything you feel interesting.

And of course enjoy it on here, mostly we rub along easily enough with our differing views but winter does tend to bring out the animal instinct in us at times.

[Frosty.]

Going by the experts there is no sign of a marked pattern change for another month at least. When you look at the models you can see the same reloading pattern we have had since winter began. However, we can't rule out the odd colder blip, similar to what we have now.

[blizzard81]

For the new folk, obviously a bit confused I would imagine, two posts, neither with charts to explain their differing views on the model outputs.

All I can suggest, I do it regularly is be patient as you gather a feeling for which poster to follow, and in the meantime try this, like I suggested last night, at least for temperature values.

Go to the charts and forecast located at the top of the Net Weather page, run the GFS model and get the temperature section to show and see what that model is actually predicting say 12 or 15Z each day for your area. Compare that to the long term average for your area for early January which you can find on the Met O website. Then make your own minds up if that sounds cold or mild.

It will also help you fairly quickly gain an understanding of the models, say GFS as that is the one most widely used with its 4 runs each day. To help you along visit the Net Wx Guides and have a browse at anything you feel interesting.

And of course enjoy it on here, mostly we rub along easily enough with our differing views but winter does tend to bring out the animal instinct in us at times.

I think most members (whether new or old) are computer savy enough to look at the models for themselves without relying on

other menbers to spoonfeed every frame to them. If not, it will do them no harm at all to find out. Lets face it, we all

had to start at some point.

Edited December 29, 2014 by blizzard81