Model Output Discussions 18z 31/01/2016

[Paul]

There are loads of posts of late that aren't really model related (stuff such as 'winters over', how annoying that is for people etc etc chiefly). It's not that these posts aren't ok,  it's just they're not ok as part of the model discussion, as they're not about the models. 

So please, if you're planning on making that sort of post, or end up writing one please stop before you submit and head over to the chat/banter/moans thread and post it in there. 

[johnholmes]

The evening output from NOAA 6-15 day anomaly charts is shown below. To me they seem to suggest what I have been seeing while on holiday from them. That is some signal for +ve heights west of the UK, perhaps a somewhat shifted Azores ridge. This coupled with -ve anomaly heights showing over and eas of the UK. Just how this pans out is obviously not that clear at the moment. It would suggest to me, on the basis of just two days of these charts, and something similar from ECMWF-GFS versions, for not mild air but no signal for any deep cold air, be that from a northerly or an easterly point on the compass.

Using the 6-10 day NOAA anomaly suggests, even with a westerly flow the air is quite cold, 534DM showing over the far south and not that much higher on the 8-14 day chart. I would suggest watching for synoptic outputs that show a prevalence for this type of airflow. Sometimes a bit south of west with milder air but fairly often from west or more north of west with colder air. Details of course on the synoptic models of wind strengths, max and min temperature values and the probable areas for any snowfall.

http://www.cpc.noaa.gov/products/predictions/610day/500mb.php

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

I've not yet had chance to look at other links; MJO etc.

Just scanning quickly some posts before mine and a lot of knee jerk reactions, in my view, to a single run. It needs saying that the synoptic models are far more volatile, winter and summer, than the anomaly charts. At time lenghts of greater than 144 hours then compare like with like, 06 to 06; 12 to 12 etc, NOT the latest run to the last one. If you do that you will spend much of your model watching being annoyed and disappointed. It needs a balanced view, synoptic with anomaly and anything else we get free access to for a balanced view to come out. Trust me, honest.

 

Edited February 1, 2016 by johnholmes
spelling

[Allseasons-Si]

24 minutes ago, Pembroke Dangler said:

It's exactly what I said last night just look at all the cold air spilling into the mid west of the u.s. Someone better tell Mother Nature what sharing means. I mean come on its farcical, even if the Synoptics fell right for us we get -2 -3 uppers at best. 

The mid west is better than the east,with a trough digging down into there it will aid WWA up the eastern seaboard,but the trouble that could come from that scenario is a west baised NAO,that's my thinking anyway but could be wrong.

Edited February 1, 2016 by Allseasons-si
spellcheck

[Paul]

Seriously, I make a request for people to use the chat thread for non-model related posts, and within 10 minutes 5 posts are made, 4 of them off topic! 

I'm moving them over to the relevant thread, but errm, please can those not doing so, consider what they're posting where - it's not a lot to ask and keeps the forum interesting and relevant for all those who want to read and take part. 

[mb018538]

ECM 12z keeps the trough over and around the UK right out to the 10th. Doesn't look like much sign of a pressure build for us at present, with the huge ridge from Baja California up to the north pole, massive trough across the Midwest, big ridge off the eastern seaboard....leaving us in the next trough along the line. Something is going to need to give this pattern a mighty big boot to break it up. Up until the middle of feb almost certainly looks like dead water now.

Edited February 1, 2016 by mb018538

[stodge]

Evening all

I certainly don't share the downbeat mood on here tonight. The GFS 12Z is a huge step in the right direction as for the first time for a few days we are starting to see some genuinely cold offerings among the various perturbations.

The number shredding the PV or pushing it away from its usual home has risen sharply today and we are starting to see a number of alternative options including rising heights over Greenland and Scandinavia and very little signs of euro-slugs and the like. 

Plenty to keep us interested in the shorter term especially at the end of the week.

 

 

[Mucka]

So ECM not what we wanted but the overall synoptic of low pressure digging South and stalling with amplification either side is there - just not in the way that would lead to cold on this run.

Expect it to be among the milder runs day 9 and 10 in the London ensembles this evening - when it is perhaps the mood will lighten somewhat? 

I have a feeling the operationals are throwing out the milder solutions at the moment. Could be a reason for that but more likely it is coincidence.

What may seem like a big swing in favour of cold may occur tomorrow yet in truth it will just be a progression of the trend we have been seeing develop.

On the other hand the Ops could be leading the way and it will be time to trade the hat for some strong rope. 

I'm still feeling positive for now though.

[Bristawl Si]

1 hour ago, Ali1977 said:

Everyone is in a hurry to get the cold here, I'm one of these too.....however, the potential is from mid month onwards so we're not really there yet...Give it time, something will crop up by the end of the week...I hope...

Thing is Ali the "potential" was end of January a couple of weeks ago; then it became early Feb.....and now it's mid-Feb.

It's worth bearing in mind that if someone says there's a chance of colder spell mid-Feb and temps likely to be below average, for down here that could mean 5 or 6c - so not overly cold.

[Banbury]

24 minutes ago, johnholmes said:

The evening output from NOAA 6-15 day anomaly charts is shown below. To me they seem to suggest what I have been seeing while on holiday from them. That is some signal for +ve heights west of the UK, perhaps a somewhat shifted Azores ridge. This coupled with -ve anomaly heights showing over and eas of the UK. Just how this pans out is obviously not that clear at the moment. It would suggest to me, on the basis of just two days of these charts, and something similar from ECMWF-GFS versions, for not mild air but no signal for any deep cold air, be that from a northerly or an easterly point on the compass.

Using the 6-10 day NOAA anomaly suggests, even with a westerly flow the air is quite cold, 534DM showing over the far south and not that much higher on the 8-14 day chart. I would suggest watching for synoptic outputs that show a prevalence for this type of airflow. Sometimes a bit south of west with milder air but fairly often from west or more north of west with colder air. Details of course on the synoptic models of wind strengths, max and min temperature values and the probable areas for any snowfall.

http://www.cpc.noaa.gov/products/predictions/610day/500mb.php

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

I've not yet had chance to look at other links; MJO etc.

Just scanning quickly some posts before mine and a lot of knee jerk eactions, in my view, to a single run. It needs saying that the synoptic models are far more volatile, winter and summer, than the anomaly charts. At time lenghts of greater than 144 hours then compare like with like, 06 to 06; 12 to 12 etc, NOT the latest run to the last one. If you do that you will spend much of your model watching being annoyed and disappointed. It needs a balanced view, synoptic with anomaly and anything else we get free access to for a balanced view to come out. Trust me, honest.

 

Hi JH

I remember looking at some of these charts before the last cold spell ( the one and only one could argue) and they were suggest decent blocking ridging down from Greenland, sadly we didn't see that .

 

 

[johnholmes]

hi B

I tend to disagree and will make a pdf to illustrate this, so hopefully you will be able to downlaod this and see my reason. Not sure how quick I can do this. I will put the relevant anomaly charts in from about 9-10 January, or if you ask I can put the whole of the January data sets in?

 

[Ali1977]

It will be interesting to see if the models start picking up on the cold spell the METO are predicting mid month, I don't think the GFS has grasped the strat warming yet so maybe some big swings out there in FI over the next few days. 

If nothing cold is coming in the first 3rd of March then bring on a nice warm and sunny spring to dry the country out !!

Pub run coming up, let's hope for some nice ridging, and some heights into Greenland.

Edited February 1, 2016 by Ali1977

[phil nw.]

Gefs ens graphs still trending cold from the coming weekend.A look at the Aberdeen and Warks. 2mtr forecasts

Whilst not promising a widespread freeze no one can argue these are mild or even average.No blocking setup but the jet tracking further south by mid-month as the Atlantic trough heads se into Europe.

GEF stamps for the jet profile.

 

Certainly it's worth waiting a few days to see if this mid-month colder signal develops into anything with polar air heading further south in week 2.

 

[johnholmes]

here with my promised pdf

pdf for Jan anomaly charts on 1 feb 2016.pdf

[Cloud 10]

GEFS and ECM ensemble mean anomalies at day 10 both shot from the same gun,with a chilly UK trough and pressure rise to the west.

 

ecm..gefs..

 

 

[winterof79]

29 minutes ago, Cloud 10 said:

GEFS and ECM ensemble mean anomalies at day 10 both shot from the same gun,with a chilly UK trough and pressure rise to the west.

 

ecm..gefs..

 

 

The emphasis seems to be going down the route of progressively colder unsettled weather. Starting this week really

http://expert-images.weatheronline.co.uk/daten/proficharts/en/euro4/2016/02/01/basis12/ukuk/prty/16020300_0112.gif

 

http://expert-images.weatheronline.co.uk/daten/proficharts/en/euro4/2016/02/01/basis12/ukuk/prty/16020306_0112.gif

Not what the majority would prefer i.e. deep freeze from the East. There will be plenty of surprise snow events and some up North i.e. Scotland,that will not come as such a surprise.

 

Edited February 1, 2016 by winterof79

[wishingforsnow]

I will only 'throw the damn towel' if it gets up to 2 weeks time and there has been consistent cross model consensus for no improvement after cold FI synoptics fail to materialise and in the case of it becoming clear that any cold spell from mid February won't happen & the Met Office and Ian should say that there's absolutely no chance of cold conditions anymore. In the meantime I would advise not to get too hung up on a single model run that either shows mild or cold as these can change. Only if it becomes a clear pattern over a week or so.

Edited February 1, 2016 by wishingforsnow

[Cloud 10]

12 minutes ago, Allseasons-si said:

Damn!!

have you got an automated keyboard,cos you cannot be that quick lol,just about to post them and i have to say that,they are looking gooood

 

LOL!

 

Just need to get the troughing a touch further east along the lines of ens.11

 

[winterof79]

This is toasty man....and not 10 days away

Edited February 1, 2016 by winterof79

[Ali1977]

10 minutes ago, winterof79 said:

This is toasty man....and not 10 days away

Do you think this is why Glosea is seeing anticyclonic possibilities late Feb?

[Allseasons-Si]

17 minutes ago, Cloud 10 said:

 

LOL!

 

Just need to get the troughing a touch further east along the lines of ens.11

 

Yes!

i was touting the west baised NAO in my earlier post,of cause it's just one ens run but hope to see more like that

17 minutes ago, winterof79 said:

This is toasty man....and not 10 days away

Toasty indeed!

and so this maybe on tomorrows update

looking at that spike of warmer air punching into the PV(above),and i could be wrong on this as i have very little knowledge on strat terminology,that that is a minor warming taking place and in the process of spiking further at the moment,judging by that if downwelling takes place(in the right place of cause),then we could encounter a colder scenario mid to late feb.

strats aside,we have just entered feb(i know we keep banging on about when will the next cold spell come),but we always get back end cold winters off a el nino,so patience all

 

Edited February 1, 2016 by Allseasons-si

[TomDav]

21 minutes ago, winterof79 said:

This is toasty man....

Impressive warming although it wanes in the longer-range and never causes a complete disintegration of the vortex (Based on latest model output)

Edited February 1, 2016 by TomDav

[damianslaw]

Moving away from the operationals, the Ensembles as posted above paint a rather cold picture, if the trough can anchor itself a bit more to the east then quite a potent NW/N blast would enfold. Alas the operationals continue to show the theme of the winter i.e. trough just coming unstuck to the west and over the country propped up by shortwave activity and phasing. We shall see what happens, the Alaskan ridge will mean a deep trough over mid west and if this holds in a more central location away from east coast of USA then we could conceivably see some warm air advection over western Greenland with a strong mid atlantic ridge, at least for a time.

There are certainly good building blocks in place for something quite cold mid month and hopefully more settled.

I'm expecting the ECM to flip back towards a colder scenario in tomorrow's runs - its operational output today goes against its Ensemble. I think the models have been a bit progressive today.. just my take on things.

[winterof79]

18 minutes ago, Ali1977 said:

Do you think this is why Glosea is seeing anticyclonic possibilities late Feb?

I couldn't really say but even though this warming is partially disregarded by those more technically challenged than myself,I have rarely seen such a warming not have some impact before long.We'll see.

[Banbury]

1 hour ago, johnholmes said:

hi B

I tend to disagree and will make a pdf to illustrate this, so hopefully you will be able to downlaod this and see my reason. Not sure how quick I can do this. I will put the relevant anomaly charts in from about 9-10 January, or if you ask I can put the whole of the January data sets in?

 

Hi JH

No please do , would be interesting to see

 

[winterof79]

Now that's more like it.Up she goes