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Paul

Model output discussion - 21st Jan Onwards

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1 minute ago, terrier said:

Maybe so frosty but that's not unusual for Scotland. And looking at the output we're all back in milder air tomorrow. With more rain and gales next week. The point I was making is these charts showing colder nationwide are always at day 10 and we always seem to be chasing that pot of gold in the charts which never seem to get any closer. 

Yes but colder weather comes back  southwards after Monday with further wintry showers, hopefully penetrating further south than currently and night frosts for a time before it turns milder again for a day or so after midweek which is soon followed by the next cold shot from the NW / N. We won't be waiting a further 10 days for colder conditions but I admit this is a very poor winter, putting it mildly, it's on a par or worse than last winter but it's not as desperate now as it was in December and Feb could bring a few decent cold snaps.:)

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Please Ladies and Genitalmans...I just hid several posts whose relationship to what the models are currently indicating seems, shall we say, 'cryptic'....And I'm useless when it comes to making sense of things that are cryptic...:D

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I dare say up north with some height will get buried, tentative signs of a mid Atlantic block on 240 some trough disruption digging into Europe, jet stream well S of UK, PV in tatters, losing the SW'ly interludes prime time to utilise. (March is going to be a cold one mark my words :D ) . The foreground is there just need a block to help funnel that cold. With chunks of PV vortex crossing over British Isles expect the unexpected very low thicknesses in mix.  I would expect to see upgrades on 850's, as what usually happens in these scenarios I believe...remains unconvincing for southern England, but this will change. We all throughly deserve some real proper wintriness nationwide from Land's End to John o'Groats following all this palava.

image.thumb.png.4834c16a1e2ff7a8e39d58f0image.thumb.png.9b2b53b1fa5d251987edf679

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Well the next 7 days looks pretty poor for cold lovers unless you are Peak District Northwards  where there is a fair chance of snow coming up  albeit coming and going between cold and less cold spells. As others have said Midlands southwards it looks pretty damp with temps around the average .

TBH it is as expected and the monthly guidelines IF has given us have been bang on and if his most recent comments come true then Southerners can't expect much in the way of snow. Not what we want to hear but still hoping for a nationwide cold spell maybe end of Feb/March.   Indeed that has been a very important  feature this winter are IF"s replies on here and although they are not what coldies want to hear(myself included) they in my eyes have been pretty accurate and the Met Office must take some credit imho.

Anyway,those in Scotland and those in the North of England and NI enjoy the snow and hope it keeps going for you:friends: 

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The latest model outputs continue to show an unsettled sometimes stormy westerly setup with the coldest air over Scotland on most days.

We already see the northern half of the UK getting snowfall in various locations under this brief Arctic feed,of course again frustrations for us further south where temperatures are just not low enough as lovely a day as it is with crisp sunshine.

The promise of a colder trend into February is still there with the ens still showing an Atlantic trough digging more se into Europe in week 2.

EDH1-240.GIF?30-12

a look at the temperature forecasts for the 2 ,3 day periods towards mid -Feb

56accd500e0db_ukt1.thumb.png.cd22db59a7156accd5c1b9d8_ukt2.thumb.png.d60eb3b8f8c

show the below normal temps. feeding further south.It looks likely apart from a couple of short milder days the north remains quite cold to the end of week 2 from the off.

A look at the 850hPa graphs for Aberdeen and London

56accdf01558d_ab850.thumb.png.38190c735156accdff5a9fe_lon850.thumb.png.51954da7f

confirming the trend.Noticeable how the colder uppers are quite predominant up north for much of the period.

The main hurdle to deep cold getting south to all is the still relatively flat jet which modifies the coldest air coming south as the flow is mainly off the Atlantic.It seems we just can't get a straight northerly at the moment.The slight ridging still promised to appear around day 10 in the ens may help to push the cold further south but at this range detail will change.

We really need a better clearance between the Canadian and Scandinavian vortex than is currently shown to see a decent pressure build and we then get a stronger feed south of true Arctic air.I wouldn't write off this possibility just yet .

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I realy liked this mornings ECM run ,ok the best charts were the last couple and so tonight we realy want to see these charts come a bit closer .

taking in what is available on the net  further outlooks SSW s etc and of course our professionals down at exeter i,m keeping my hopes up for maybe after next weekend ,but i,m ready for a fall as this hobby is full of let downs if you are chasing your dream synoptics .

Gfs now rolling out and soon the main models will be setting out their thoughts ,we have had a sniff of the Arctic lets get plastered ,cheers gang catch you all up later .:yahoo:

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Lots of ups and downs from those viewing individual model runs.  However even now we are only at the very edge of beginning to view the period that the Meto

have marked out as a period for colder than average weather. So nothing unusual in seeing a mainly westerly outlook for the time being. For now there is simply to much west to east motion energy in the northern hemisphere set up for anything other than transient cold tucking in behind the passing depressions.

It will change as the seasonal wavelengths start to take effect hence the Meto's continuing confidence in the mid month change to colder than average.

Don't forget even average conditions allow some snow to fall ( even in the south) so even slightly below average conditions would see an increase in that potential.

 

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Going by the above graphic I struggle to see how UK would miss out..

A meaty ridge indeed! 

image.thumb.png.248e44215cad27a19921a395

 

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Crazy cold into the USA

image.png

Followed by a new huge PV...let's hope FI is clueless.

image.png

The lack of comments when an SSW is coming says it all - at the minute nothing showing UK wide cold. Tick Tick Tick.........

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32 minutes ago, Daniel* said:

Going by the above graphic I struggle to see how UK would miss out..

A meaty ridge indeed! 

image.thumb.png.248e44215cad27a19921a395

 

I think he is refering  for the US only ' i could be wrong though .

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Can't really see any cheer on the gfs 12z tonight more storms next week and heavy rain. Looking into the realms of fi we have a huge pv reforming. Brutal cold in the states firing up the jet straight across the Atlantic straight at the uk. Not convinced Feb will rescue this winter to be honest. Let's see what ecm has to say. 

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4 minutes ago, Cloud buster said:

I think he is refering  for the US only ' i could be wrong though .

Yep! The brutal cold has been well forecast for north east US now for a few days, in a couple of weeks they could be in the deep freeze. Unfortunately for us this could mean a procession of storms heading our way, as last winter. 

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6 minutes ago, Mark Griffin said:

Surely brutal cold in the states would only serve to fire up that jet stream further?

It can cause something that happens regularly, rapid cyclogenesis pushing dartboard lows across to us on the jet stream. Not good news at all!

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Looking at that ECM ens. mean for days 11-15 it's easy to see what we need, but what is sorely missing from the GFS runs of late; a sharp enough trough over the U.S. that even a deep low struggles to progress east and topple the ridge trying to gain a foothold in the Atlantic.

This is genuinely achievable I think; the ECM 00z seemed to be setting things up nicely and so is the GEM 12z. No surprise that these models are more enthusiastic with their MJO projections.

GFS is currently adapting what it does with the AAM and has started to see the rise as the MJO gets going, but then drops it off again which essentially gives it an excuse to beef up the westerly momentum... with dramatic results on the 12z det. run.

 

So as far as I see it, the tropical forcing could still deliver at least a cold snap with a heightened snow risk for a few days across much of the UK *BUT* I think it will need to gather strength sooner rather than later - ideally faster than current model projections - in order to coincide with the more vulnerable vortex state. This being in case the vortex does manage to retain some composure by mid-month and in an undesirable location.

There's more to the desire for faster MJO progression than the above, though. At some point this month it'll arrive in phase 8, probably with decent amplitude, and that correlates to these anomalies during a typical El Nino Feb:

FebENMJOphase8gt1500mb.gif

I know - talk about dangling one hell of a carrot! The question then becomes how much this is modified by the fact that this year's event is basin-wide and coupled with a warm Indian Ocean. Should there also be a SSW by then... well, lets just say the back end of the month and March may prove very un-springlike indeed. This is not something I like the idea of very much to be honest, as March 2013 was wretched down here with bitter winds but no lying snow or even much ice. It's just what seems more and more inevitable unless the warming in 10 days time manages to go the whole hog despite GFS saying 'nope'.

 

There is a reason why I've never explicitly predicted Feb to feature good chances for snow in lowland southern England for example - so much risk of it being a case of 'almost, but not quite' with the blocking pattern. I'd give the middle 10 days of the month a probability of around 25% at the moment, this most likely coming from a mid-Atlantic ridge gaining a foothold to the west and then, when it does topple, 'resting'on top' (N. of) of a Euro trough for a short spell. 

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@Cloud buster

You're correct, well he is from states.

It would have wider implications the ridge pumps WAA right into the heart of pole giving way to a domino effect, in HLB there would be ripples. The +ve height anomalies in those regions suggest arctic air will be dislodged to our latitudes, North America & Western Europe it seems to me, arctic floodgates would open for us included. It would be incredibly unfortuante if we got nothing decent, very cold air which has spent its time bottled up in arctic circle, not saying to the extent what the U.S is expecting to see-but much colder conditions that is how I'm interpreting it. It does take us near to mid February but to be realistic anything earlier would have been a bonus, the winter is not going out with a whisper. This time next week I sense we will be seeing some really striking model output, just hold on tight and enjoy the ride...

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1 hour ago, Cloud buster said:

I think he is refering  for the US only ' i could be wrong though .

I'm not sure as he does mention the block into Greenland, he also say's " open the flood gates" but they already are in the States . I think he is hoping for something UK side

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Afternoon All-

Im afraid at the moment - im not quite sure why there is some sort of celebratory cheer towards the forecasts around these global teleconnections as they are a total bust.

( note im not linking this to the net weather winter forecast ) - although I would have to reread it -

The reality of what been put across is almost the inverse of whats actually happened with this 1983 template.-  There may be of course resemblance is the bigger picture of globe in terms of the AAM Spike & the more significant teleconnections like the Nino base state / WQBO etc - however when push comes to shove the forecast output generated from using these analogues has been next to useless.

 

Here Is the 1983 template to the dates proposed -

56acf0972ffef_1983template.thumb.gif.db3

Here is the current anomalies

56acf121c4660_2016comparsion.thumb.gif.c

 

Whilst there are some weak similarities over Canada & Russia with positive heights - that's about as close as it gets to a match & certainly no 'classic -NAO' that was touted or even a west based one for that matter-

The biggest significant difference is the location of the anomaly of low heights - note nothing to get excited about over Scandi - as all the low heights are in the atlantic. Also comparing the NAO to projection - its a classic positive & the AO has changed modality in that timeframe from -5 to + 4- that's about a big a swing to mild as was the swing to mid latitude cold at the start of Jan-

There is (sadly for the UK) no comparison.

We are now through January & we should be talking ( again) about the possibility of the warmest Winter on Record, not of sustained cold.

As it stands the Record DJF CET is 6.77 in 1869 With the current projections being 9.7 December & 5.6 ~ ( 7.65 combined)  then we only need 5.1c to beat the record )

Week 1 looks changeable & about average - there after the Glosea / Met office forecasts continue to paint a picture of Westerly / North westerly influenced weather which would preclude more averageness- circa 5c.

It could all go down to the last 2 weeks of Winter...... - Maybe finally the much touted stratospheric change will gallop down the final furlong to save the 'ice' day- lets hope so. but how anyone can claim any success or any related cold success in a winter that will more than likely arrive at the very least in the top 5 warmest surprises me ( we need 3.59 to come in 5th)

it all underpins & reinforces my opinion that the 2 caveats in this teleconnection snake pit will continue to overrule any forecasts for the UK - they are

* Analogues in terms of forecasting anomalies based on historic years will now never work because the globe is changing at a rate that's probably faster than ever before & our little data reanalysis covering 1948-2015 ( 63 years ) when compared with how many global teleconnections there are will ensure that there are probably ZERO true analogues - combine that with the rate of change of the globe & you get maybe 3-5 semi close matches from history - but when you arrive at the winter the close match becomes irrelevant this is because With global warming & ice melt the jet stream is going to be located in different places to start with - that's perhaps not so bad in itself- however that creates significantly different feedback loops than were observed in the years gone by - hence zero analogues.

 

* Analogues based on rough locations of High pressure anomalies Don't work - ( maybe at a global level - even at a continental level ) but if you scale the globe then NW Europe becomes micro scale & the UK is Macro scale - IE the correlation graph between The global teleconnection used in the forecasts ( AAM ) has probably at best a very weak correlation for NW Europe & a waif like correlation with the UK ( IE less that statistically important )

 

Anyway- the models continue to show what they have all winter for the UK- low heights & westerly flow. The kara ridge delivered deep cold into central Europe & The huge block over the western states ( EPO ridge rather than PNA ridge) will deliver deep cold to central states - with the E/NE states on the periphery if the dreaded SE ridge sits there like the euro slug.

The arctic high remains of interest - but sadly this will never deliver cold to the UK unless it supports a link up with an atlantic ridge - & so far this winter its been totally absent infact I will leave you with the anomaly summary of winter so far...

WINTER 2015/16 = FAIL.

500 ANOMALY

56acf9c614598_WINTERTODATE.thumb.gif.ddd

ZONAL WIND - EASTWARD ENERGY + 12 M/S across the atlantic

56acfa02195e5_2016ZONALWIND.thumb.gif.9e

& 10MB Strat Anomaly

Strat.thumb.gif.b649b5ba377647dc8208a098

Its nearly over for another year- only a decent strong Propergation from the stratosphere would save us in Feb ( Or march )

S

The best chance for the UK will now always be in the 10-20 Feb range if the Massive EPO ridge can create enough change jet profile to allow an atlantic ridge to build ( not a transient one )

 

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A sobering post Steve, but no surprise to me, even though i have no where near the knowledge of some on here.

 

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GEFS out to 15th Feb are strongly zonal. Of course they can 'flip' and are not to be taken literally, but there is nothing hinting at any change.

As Steve says above i suspect the main issue for Feb will be whether we get over the line for our warmest ever winter. If we do, I'd wager its a record that won't stand for very long.  

 

 

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Honestly peeps - do some of you actually think that the weather waits, on tenterhooks, until a certain guru makes a prognostication? All folks can do is use their knowledge to the best of their ability...Maybe we should go back to the Golden Age of animal entrails?:D

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Thanks for that post Steve  I agree with every word.

Back to the models and zonality is definitely trending colder. Another severe cold spell over in the US really would be remarkable. Of course they being quite dubious about Global warming doesn't help matters as they seem to be hoovering up whatever cold is going in the Northern hemisphere 

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13 minutes ago, Ed Stone said:

Honestly peeps - do some of you actually think that the weather waits, on tenterhooks, until a certain guru makes a prognostication? All folks can do is use their knowledge to the best of their ability...Maybe we should go back to the Golden Age of animal entrails?:D

I read somewhere that in ancient Rome they were pretty good at forecasting storms at sea through examining animal livers, maybe there was something to it then..:rofl:

 

In the meanwhile maybe something there again developing in deepest FI on the ECM....

ECM1-240.GIF

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Advice to all folks - stick to the NWP up to 144 hours - that way you won't be disappointed.  Yes, you can get one of the over-amplified ECMs showing within 144 hrs but if there is no cross model support then no need to get carried away.

Anyway, the NWP up to 144 hours is again pretty underwhelming - zonality all the way!  The writing is on the wall folks - it's possible that the last two weeks of February may 'save' this winter but the mildest winter on record is surely on.  That's the REAL story as Steve M alluded to above.

UKMO probably the 'best' at day 6

Rukm1441.gif

 

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