Model Output Discussion 19th January 2014-18z onwards.

[ItNeverSnowsInWindsor]

There's too much uncertainty with the models to be even 50% confident of a wintry outlook next week. I can see the reluctance by some posters to say it will get properly cold next week.

 

For e.g. the GFS 6z has backtracked somewhat with more energy going NE'. There's too many IFs and BUTs. If I see the same prognosis from UKMO at 12z tomorrow then I may be more inclined to getting excited.

[shedhead]

Hi Im not a regular poster, but as the jet dives south right over the U.K, wouldn't that aid in the diversion of low pressure south under any block to the east? Thanks in advance

In the ideal world you want it diving SE'wards to the SW if us, but not so far as to keep the LP's out of range.

Edited January 23, 2014 by shedhead

[steelermark]

I think the upcoming spell has all the markings of a spell of weather I remember as an 8 or 9 year old. Not sure if it was 78 or 79 but we were travelling back from Manchester to Sheffield over the snake pass and we'd left early due to the weather forecast saying there was a big battle between east and west right above our heads. It was throwing it down with rain in Manchester but obviously going over the snake would be different. It was snowing heavily on the snake pass but raining very heavily in Sheffield at the other side.

 

I remember the forecasters saying it should stay as rain for us so I went to bed disappointed. Imagine my surprise when I woke up in the morning to nearly 10" of snow. Everything was wet through at 10pm the previous evening, puddles everywhere. It stayed on the floor for a week.

 

So looking through the models now , it just looks a very similar event coming up. Not sure anyone can confidently say which way it's going just yet. Us coldies may be left disappointed again but the people calling mild continually may well get egg on their faces come next weekend.

Edited January 23, 2014 by steelermark

[snowice]

....hence the high entropy marking the uncertainty of how the change will be manifested and when. Moreover detailed assessment is only out to Tues currently. What happens Weds onwards is an open book re wintriness etc.

 

 

This is like the Ipcress file, fascinating stuff.

 

Great model watching days ahead so?

[tight isobar]

The issue IMO going forward is will we see the same trend of recent weeks repeated? its obvious from across the model suites that they have had the pattern too far east in their FI's. I'm sure the UKMO would have noted this and even though their ensembles and other products might be saying one thing I would be surprised if their forecast did not have a caveat included for that eventuality. I don't expect them to produce a more wintry update today but would expect the wording re a chance of more snow or colder weather to be included, we'll see when it comes out.

yes, I don't think the met update will read dramatic.however I expect to see the word DOUBT, appear quite widely going forward! ?

[tight isobar]

yes, I don't think the met update will read dramatic.however I expect to see the word DOUBT, appear quite widely going forward! ?

doubt not being the word . perhaps unsure more suitable.

[karlos1983]

There's too much uncertainty with the models to be even 50% confident of a wintry outlook next week. I can see the reluctance by some posters to say it will get properly cold next week.

 

For e.g. the GFS 6z has backtracked somewhat with more energy going NE'. There's too many IFs and BUTs. If I see the same prognosis from UKMO at 12z tomorrow then I may be more inclined to getting excited.

 

There's only one IF 

 

London 00z 

 

 

Something odd happens on the 31st? little agreement there.

 

GEFS not really in agreement at +192 with the GFS

 

GFS

 

GEFS

Edited January 23, 2014 by karlos1983

[BLAST FROM THE PAST]

Luckily for us coldies, nothing is set in stone! Looking at a 10 - 15 day trend counts for nothing at the moment IMO. In the mean time we have a lot of rain to get through before a shot at some colder weather at last!

Indeed Fred and MetO, other professionals, amateurs, alternatives...the models particularly have all not been correct.....we are at the junction of up for grabs IMO.

 

 

BFTP

[BLAST FROM THE PAST]

Hi Im not a regular poster, but as the jet dives south right over the U.K, wouldn't that aid in the diversion of low pressure south under any block to the east? Thanks in advance

It means much less [if any] energy would go NE.  However, we could just get a trough stuck to our W / WNW as has been experienced...de ja vu?

 

BFTP

Edited January 23, 2014 by BLAST FROM THE PAST

[bluearmy]

ecm ens pattern is firming up on a continuation of the status quo. canadian vortex, alsakan ridge, scandi ridge, azores high which waxes and wanes with the next system that comes off the eastern seaboard in association with another burst from the vortex. the systems traversing the ridge and dropping into europe. each episode begins with the ens mean progging the track east of the uk and this then corrects slowly west so that the anomolys drop through the uk. we now see next week agreed upon and although the ops seemed to want to drive the jet ne, the ens are firming up on the next trough dropping in and the ops slowly catching on. so next weeks set up likely to be broadly repeated days 9 through 12. interestingly, the anomoly to follow this one seems to be able to come in on a flatter trajectory (not iceland se towards us) as the atlantic ridge seems to back west somewhat. should the same corrections apply due to the blocking being stronger we may well see some more obvious battleground charts cropping up soon in week 2.

[492]

Events do seem to be unusual again this year with weeks and weeks of exceptional storminess and now an apparently immovable trough over the UK and a block of high pressure sitting over Northern Scandianvia of no great intensity but of unusual persistence when compared to the last 25 years or so. The presence of this pattern has caused the cold over Scandinavia and NW Russia to intensify and expand in all directions e.g -15C in Poland this morning. So far the UK has remained on the edge of the cold but as the cold intensifies over Europe there must be at least a worry that this intense cold will very gradually expand further and further west eventually engulfing the UK.   

[shedhead]

ecm ens pattern is firming up on a continuation of the status quo. canadian vortex, alsakan ridge, scandi ridge, azores high which waxes and wanes with the next system that comes off the eastern seaboard in association with another burst from the vortex. the systems traversing the ridge and dropping into europe. each episode begins with the ens mean progging the track east of the uk and this then corrects slowly west so that the anomolys drop through the uk. we now see next week agreed upon and although the ops seemed to want to drive the jet ne, the ens are firming up on the next trough dropping in and the ops slowly catching on. so next weeks set up likely to be broadly repeated days 9 through 12. interestingly, the anomoly to follow this one seems to be able to come in on a flatter trajectory (not iceland se towards us) as the atlantic ridge seems to back west somewhat. should the same corrections apply due to the blocking being stronger we may well see some more obvious battleground charts cropping up soon in week 2.

Agree, still looks like the best we can hope for at this stage, but unfortuantely this kind of set up could well worsen the prospects for further flooding in this neck of the woods, as Atlantic fronts become slow moving and maybe even stall. However at this stage any stalling looks most likely to occur farther eastwards.

Edited January 23, 2014 by shedhead

[AWD]

Unless I'm otherwise mistaken, the high res NAE model has finally been put to sleep.

RIP NAE.

[Summer Sun]

Unless I'm otherwise mistaken, the high res NAE model has finally been put to sleep.

RIP NAE.

 

I can't see it either on weather online http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=ukuk&MODELL=gfs&MODELLTYP=1&BASE=-&VAR=prec&HH=3&ARCHIV=0&PANEL=0&ZOOM=0&PERIOD=

Edited January 23, 2014 by Summer Sun

[shaky]

I thought nae went to sleep a few months ago!!

[fergieweather]

Unless I'm otherwise mistaken, the high res NAE model has finally been put to sleep.RIP NAE.

Nope.UKMO assessment on 00z suites as previous. Snow NE especially Tues-Thurs etc; perhaps spell of snow W/NW later in week as westerly mobility returns. Low confidence on detail/timing with marked entropy spike d8-9. Thereafter high confidence on return to broadly zonal pattern "as seen so far this winter" albeit with around 10% EPS/MOGREPS showing varied interruptions through deep lows etc, some with easterly components. Anyway, detail Tues-Sat trickiest but UKMO not currently concerned re major snow threat for e.g. southern England (but it is too far away anyway to be given much detailed attention). In any case, all their focus on disruptive weather is tomorrow and Sunday, understandably.

[Man With Beard]

Jet looks set to power up significantly on this run, so IF correct there looks a real danger that the Atlantic could come crashing on through later next week. Any sort of sustained cold looks very unlikely based on this.

 

But if the jet keeps jetting off to Portugal, we may keep this run of splitting, perhaps even diving lows going ... keeping us in the corridor of uncertainty with regards rain or snow?

[Summer Sun]

Looking at today's text update from the met Tuesday to Thursday looks the best chance of seeing some wintry showers in the east / north east before a return to westerly winds from Friday

 

Unsettled through Tuesday and Wednesday with showers or longer spells of rain, wintry in the northeast where it will feel cold in the strong easterly winds. Elsewhere, temperatures will be near, or just below, normal and it will be windy in the southwest, risk of overnight fog and icy patches.

 

Less unsettled with sunshine and some showers on Thursday; perhaps wintry in the northeast/east.

 

However, a return to westerly winds is expected from Friday, with further outbreaks of rain, hill snow in northern Britain, and strong winds

[mcweather]

ecm ens pattern is firming up on a continuation of the status quo. canadian vortex, alsakan ridge, scandi ridge, azores high which waxes and wanes with the next system that comes off the eastern seaboard in association with another burst from the vortex. the systems traversing the ridge and dropping into europe. each episode begins with the ens mean progging the track east of the uk and this then corrects slowly west so that the anomolys drop through the uk. we now see next week agreed upon and although the ops seemed to want to drive the jet ne, the ens are firming up on the next trough dropping in and the ops slowly catching on. so next weeks set up likely to be broadly repeated days 9 through 12. interestingly, the anomoly to follow this one seems to be able to come in on a flatter trajectory (not iceland se towards us) as the atlantic ridge seems to back west somewhat. should the same corrections apply due to the blocking being stronger we may well see some more obvious battleground charts cropping up soon in week 2.

 

It will be interesting BA to see if that turn of events comes about, I wonder if we might see a  Jan into feb scenario akin to 1978 developing, obviously that particular situation hugely favoured my corner of the the UK.

[shedhead]

Nope.UKMO assessment on 00z suites as previous. Snow NE especially Tues-Thurs etc; perhaps spell of snow W/NW later in week as westerly mobility returns. Low confidence on detail/timing with marked entropy spike d8-9. Thereafter high confidence on return to broadly zonal pattern "as seen so far this winter" albeit with around 10% EPS/MOGREPS showing varied interruptions through deep lows etc, some with easterly components. Anyway, detail Tues-Sat trickiest but UKMO not currently concerned re major snow threat for e.g. southern England (but it is too far away anyway to be given much detailed attention). In any case, all their focus on disruptive weather is tomorrow and Sunday, understandably.

Oh dear, does that possible return to a zonal pattern carry the same level of rain risk down here Ian, or does it want to lift the bigger totals farther north and give us some Azores ridging?

Edited January 23, 2014 by shedhead

[Man With Beard]

Nope.UKMO assessment on 00z suites as previous. Snow NE especially Tues-Thurs etc; perhaps spell of snow W/NW later in week as westerly mobility returns. Low confidence on detail/timing with marked entropy spike d8-9. Thereafter high confidence on return to broadly zonal pattern "as seen so far this winter" albeit with around 10% EPS/MOGREPS showing varied interruptions through deep lows etc, some with easterly components. Anyway, detail Tues-Sat trickiest but UKMO not currently concerned re major snow threat for e.g. southern England (but it is too far away anyway to be given much detailed attention). In any case, all their focus on disruptive weather is tomorrow and Sunday, understandably.

"deep lows with easterly components" - to me that does not suggest the ECM route post D8 which would not have any easterly components I think, instead it is more like the GFS which maintains a little blocking to the north but not enough to sink the Atlantic pattern below our lattitude Edited January 23, 2014 by rjbw

[fergieweather]

Oh dear, does that possible return to a zonal pattern carry the same level of rain risk down here Ian, or does it want to lift the bigger totals farther north and give us some Azores ridging?

Impossible to be prescriptive. Even next week is tricky enough and no-one at UKMO will discount more wintry possibility given ongoing variance in model handling of low track/shape, entrainment of colder air etc. But that is still a few days away, so not a pressing forecast issue.

[mickpips]

Looking at today's text update from the met Tuesday to Thursday looks the best chance of seeing some wintry showers in the east / north east before a return to westerly winds from Friday

 

Unsettled through Tuesday and Wednesday with showers or longer spells of rain, wintry in the northeast where it will feel cold in the strong easterly winds. Elsewhere, temperatures will be near, or just below, normal and it will be windy in the southwest, risk of overnight fog and icy patches.

 

Less unsettled with sunshine and some showers on Thursday; perhaps wintry in the northeast/east.

 

However, a return to westerly winds is expected from Friday, with further outbreaks of rain, hill snow in northern Britain, and strong winds

What i see as the main point you failed to post SS is their forecast thereafter of temperatures being 'rather cold' but nearer normal at times in the south. That still indicates below average temperatures for the majority even beyond next weds/thurs

[Troubleatmill]

Oh dear, does that possible return to a zonal pattern carry the same level of rain risk down here Ian, or does it want to lift the bigger totals farther north and give us some Azores ridging?

 

We are all wet and flooded Shed, England, Wales Scotalnd and Ireland so lets hope (if it cant stay cold) that any return to zonality heads way way North, really need it get cold to get the dew's and wet bulb temps down to dry eveything up a bit 

Edited January 23, 2014 by Nicholas B

[nick sussex]

The ECM ensemble for De Bilt chopping and changing with more colder solutions today:

 

Last nights 12hrs run:

 

 

This mornings 00hrs run:

 

 

You can see the increasing colder solutions brought forward, this as a result of a cluster of those ensembles having a more favourable low near the UK and better trough disruption.

 

Now of course De Bilt given the pattern could be on the colder side of any troughing but these are still a good indication of the strength of any blocking to the east/ne.

 

PS you do have to factor in the scale which sometimes changes to accomodate the spread but still a decent increase in colder outcomes.

Edited January 23, 2014 by nick sussex