Model output discussion pm 13/01/2016

[Yarmy]

47 minutes ago, IDO said:

Yes you could be right with the 12z. The UKMO has verified lower then the GFS in 7 of the last 8 12z runs at D6. It is also rare that the UKMO does not verify better over the previous 31 days, they are the same at the moment:

 

 

While not disagreeing with your general point, it's of course not the last 8 12Z runs; it's the 8 12Z runs from Jan 2nd to Jan 9th. We'll have to wait before we know how the past week has verified. 

Edited January 16, 2016 by Yarmy

[Summer Sun]

Fairly good agreement between UKMO at ECM at t144 after a week of little rain it could be all change next week with rain and stronger winds making a return

The question is will the breakdown be preceded by snow

Edited January 16, 2016 by Summer Sun

[nick sussex]

Good agreement growing now for a breakdown towards the middle of the week. The uncertainty perhaps in the angle of the breakdown and whether there would be any snow before the milder air moves in.

[igloo]

slowly but surley the JET and the PV are  taking over again from mid week onwards i think we will need a SSW event soon or the netweather winter forecast for febuary will be spot on again for another very mild month

 

Edited January 16, 2016 by igloo

[wishingforsnow]

25 minutes ago, igloo said:

slowly but surley the JET and the PV are  taking over again from mid week onwards i think we will need a SSW event soon or the netweather winter forecast for febuary will be spot on for another very mild month

 

 

Further down the line there have been growing signals and models suggesting blocking returning and PV weakening after the Atlantic incursion (charts for 31st January although they are still deep FI). 

MO today and for the past few days mentioned a breakdown of the current cold conditions and Atlantic dominated weather to return for a while next week after this current cold spell ends however they are now also stating potential for colder conditions increasing as we enter February. And they have access to more advanced models and sources of data to provide short and long term outlooks. I estimate a short period of zonality for mid/end January but in considering the current state of the atmosphere and conditions in Continental Europe and Scandinavia, yes, there probably will be a breakdown of this current block but on the other hand I don't think there will be a full return to the mild and wetness of November and December for February and the rest of winter after this return of the Atlantic occurs. It may not be over for cold, but only just beginning 

Edited January 16, 2016 by wishingforsnow

[TSNWK]

Breakdown.. Gaining support today.. But hey! By then it would have been a week.. Not exceptional, but with some luck there will be decent covering tonight for some.. Followed by some cold days.

lets see that out.. Live for the moment! And if we are lucky the next cold spell will be shining as this one ends.

I'm off to the regionals

Edited January 16, 2016 by TSNWK

[minus 9]

Been reading the forum for 5 years now. I think we need to understand the models, they only show what might happen(not what will.). 

[Banbury]

36 minutes ago, igloo said:

slowly but surley the JET and the PV are  taking over again from mid week onwards i think we will need a SSW event soon or the netweather winter forecast for febuary will be spot on again for another very mild month

 

Out of curiosity why do you think we need a SSW ??? we were in a hell of a run of mild swly winds and this cold snap came from nowhere without the help of any SSW

[wishingforsnow]

6 minutes ago, minus 9 said:

Been reading the forum for 5 years now. I think we need to understand the models, they only show what might happen(not what will.). 

 

Yes, they are guidelines for current and possible future weather but the actual weather has sometimes been different to patterns shown in the models, and flips to the opposite occurred sometimes at the last minute i.e 1 or 2 days before the supposed 'weather event' was to happen such as the famous 'failed Easterly' of December 2012. 

Edited January 16, 2016 by wishingforsnow

[Gazza H]

2 minutes ago, Banbury said:

Out of curiosity why do you think we need a SSW ??? we were in a hell of a run of mild swly winds and this cold snap came from nowhere without the help of any SSW

I would say the current weather is typically seasonal. A SSW would increase the chances of a much longer sustained cold spell

[Polar Maritime]

Can we please move on to what the models are showing please, Thanks.

[Timmytour]

57 minutes ago, Mucka said:

Disappointing ECM tonight moving toward UKMO.

Game ,set and match Atlantic or more fun and games tomorrow?

We will have to see how the PV behaves after the Atlantic gets in but NH profile doesn't look too bad,

Didn't want to retain the whole quote, but don't know how to edit?

Anyway.....the bit I wanted to leave was ""disappointing ECM tonight moving toward UKMO"

That, from someone I regard as one of the best posters on this forum, sums up where we are.   Three days ago I would have been cheering to the rafters to read such a statement...now it's a disappointment!!

I am not aware of the first  cold spell in a  January being of of any length without something in the preceding December having led the way.

The models may show an uninspiring view after the mild comes in.....but the Cold has had a taste and iet will be back!!!  This is not the winter of the last two years!

[johnholmes]

Not sure what to make of the anomaly charts, all 3 show a strong Atlantic flow into the UK arriving from south of west but with the ridge holding on all e and showing signs of strengthening perhaps. Heights rising re the anomaly in the far north off Norway, so links below

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

http://www.cpc.noaa.gov/products/predictions/610day/fxus06.html

 

[chris55]

The big three all have the milder south/southwesterly flow at T120. For the first time in a while, after the finer details of the beginning of the week, we have unanimous agreement on the cold/cool air leaving our shores.

Its not a foregone conclusion as the GFS 12z ens show, although the towel is ready and so is the fat lady! ha.

 

[wishingforsnow]

2 minutes ago, chris55 said:

 

9 minutes ago, johnholmes said:

Not sure what to make of the anomaly charts, all 3 show a strong Atlantic flow into the UK arriving from south of west but with the ridge holding on all e and showing signs of strengthening perhaps. Heights rising re the anomaly in the far north off Norway, so links below

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

http://www.cpc.noaa.gov/products/predictions/610day/fxus06.html

 

So further possible evidence in models that this current cold spell ending does not mean curtains for further cold over the UK? 

And it would be a nice little miracle if the cold did end up surviving next week although its extremely unlikely. But that doesn't mean it won't be back at all.

[nick sussex]

Well the ECM postage stamps show many options for as early as T96hrs. Ranging from damp squib breakdown to something a lot more interesting.

http://old.ecmwf.int/samples/d/inspect/teasers/samplers/banner/mean_sea_level_pressure_and_temperature_at_850hpa!96!pop!od!enfo!enplot!2016011612!!/

As a general rule you're looking for the ones with low pressure to the west negatively tilted, or at worst neutral, also the ones that dig further south towards Biscay.

At this range you'd have to factor in the operational run as having a better handle on things given its higher resolution but just going off that mix of ensembles anything could happen re this breakdown.

 

Edited January 16, 2016 by nick sussex

[A Frayed Knot]

Fergies reply in the SW Thread just now .

Lot of fretting folk. The modelling Mon-Tues has always leaned towards weakening frontal progression but nonetheless, MOGREPS has fair prognosis of 1cm(+) snow for Monday across E'rn W Country (Wilts/Glos)... Clearly not to be taken too literally. The key thing is a general muting of PPN signal early this week... however in medium range, key disclaimer is best left to my UKMO colleagues who wrote an hour ago: "...Despite the model convergence, because it is towards a more mobile solution rather than the previously blocked pattern, confidence is still only moderate at best..."

In other words, we do expect eventual mobility of sorts, BUT anyone taking current models at face value into medium range is missing wood for trees. Creep to climatology is, let us remember, NWP 'default'....

[phil nw.]

20 minutes ago, johnholmes said:

Not sure what to make of the anomaly charts, all 3 show a strong Atlantic flow into the UK arriving from south of west but with the ridge holding on all e and showing signs of strengthening perhaps. Heights rising re the anomaly in the far north off Norway, so links below

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

http://www.cpc.noaa.gov/products/predictions/610day/fxus06.html

 

Yes John that seems the way the height anomalies are going by day 10 on the ECM/GFS ensemble forecasts this evening.

back to the familiar Greenland trough Euro/Scandi. heights at least for a while.Maybe not too unsettled further south and east as high pressure could well setup nearby.Hopefully a drier version of a south westerly pattern than December was with temperatures closer to average.

Depending where any high sets up we could still see some night frosts,a lot depends on any cooler continental flow.

Edited January 16, 2016 by phil nw.

[Ali1977]

3 minutes ago, phil nw. said:

Yes John that seems the way the height anomalies are going by day 10 on the ECM/GFS ensemble forecasts this evening.

back to the familiar Greenland trough Euro/Scandi. heights at least for a while.

 

Could this lead to a proper Scandy block?

[chrisbell-nottheweatherman]

Weatherweb have amended their February forecast based on the CFS anomalies (or at least are on the verge of amending it).  They now suggest an ever-strengthening Jet with lower heights to the north and higher heights to the south, bringing a mean westerly flow - wet and windy conditions prevailing.

EDIT:  Forgot link - apologies.

 

 

Edited January 16, 2016 by chrisbell-nottheweatherman
Added video

[phil nw.]

1 minute ago, Ali1977 said:

Could this lead to a proper Scandy block?

Hi Ali,I added a bit more while you posted!

Not likely in the next 2 weeks as the heights are orientated from Europe.There are just hints at the end of the ens run of GP's Atlantic/Greenland +ve ht anomalies though

I didn.t want to highlight it yet as it is right at the end and i would wait for a 2/3 more runs before thinking it might be a trend to follow plus i don't want to jinx it!

[wishingforsnow]

Might slightly be off topic for models specifically but Matt Hugo's latest tweet suggests 'a return to December weather is not expected' @MattHugo

[BLAST FROM THE PAST]

1 hour ago, Banbury said:

Out of curiosity why do you think we need a SSW ??? we were in a hell of a run of mild swly winds and this cold snap came from nowhere without the help of any SSW

Absolutely, helpful but not the guarantee [although I think we'll get some kind of SSW back end of the month] .  This cold period is not bad and is due to run for some days yet.  As RJS and as I support some mild attempt is coming and likely to make inroads...but not win out.  I'm looking for some deep LP systems to take over and bring a renewed colder shot and at last I like the look of this FI

http://max.nwstatic.co.uk/ecmimages/20160116/12/ecmt850.216.png

 

http://max.nwstatic.co.uk/ecmimages/20160116/12/ecmt850.240.png

 

real cold shot from our North to develop from there

I anticipate a lot more drama ahead...beyond the drama that lies immediately ahead

 

BFTP

 

Edited January 16, 2016 by BLAST FROM THE PAST

[wishingforsnow]

6 minutes ago, phil nw. said:

Hi Ali,I added a bit more while you posted!

Not likely in the next 2 weeks as the heights are orientated from Europe.There are just hints at the end of the ens run of GP's Atlantic/Greenland +ve ht anomalies though

I didn.t want to highlight it yet as it is right at the end and i would wait for a 2/3 more runs before thinking it might be a trend to follow plus i don't want to jinx it!

From this setup I think it echos the current MO extended outlook for the next 2 weeks, unsettled few days here and there at first, then a more settled colder South of the UK whilst North slightly more unsettled though they could still see further snow up there. Not a complete return back to square 1 blowtorch Euro High domination as Europe itself is much colder than the snow starved landscape it was 4 weeks ago and there is good potential for a further Scandi block in there to form 

Edited January 16, 2016 by wishingforsnow

[ALL ABOARD]

12 minutes ago, chrisbell-nottheweatherman said:

Weatherweb have amended their February forecast based on the CFS anomalies (or at least are on the verge of amending it).  They now suggest an ever-strengthening Jet with lower heights to the north and higher heights to the south, bringing a mean westerly flow - wet and windy conditions prevailing.

EDIT:  Forgot link - apologies.

 

 

Cfs cant even predict next weeks weather let alone next months