Model Output Discussion - 18z - 25th Nov onward

[BOMBHEADS]

uk met is still holding strong this morning.

[swfc]

Very promising H5 anomaly update

Svalbard+arctic high staying strong... expect the nwp to be measured and move towards this solution through the next few days-

hi.can you put this in laymens terms as im not sure what were seeing here .thanks Edited November 26, 2012 by swfc

[Paul]

Just a reminder, if you are getting a bit annoyed with someone's posts, we have the ignore function so you can stop them from appearing for more stress free model thread viewing

http://forum.netweather.tv/index.php?app=core&module=usercp&tab=core&area=ignoredusers

[Polar Maritime]

No change this morning.The blocking is still the firm trend.

Models are still struggling with the block as usual,even within the reliable time frame, so still lot's of chopping and changing before a clean evolution can be seen. I have noticed the BBC now bringing the word cold into the forecast's for midweek..

A very good start to winter coming up, be patient and don't take every run as gospel...

Edited November 26, 2012 by Polar Maritime

[Frosty.]

No change this morning.The blocking is still the firm trend.Models are still struggling with the block as usual,even within the reliable time frame, so still lot's of chopping and changing before a clean evolution can seen. I have noticed the BBC now bringing the word cold into the forecast's for midweek..A very good start to winter coming up, be patient and don't take every run as gospel...

Just heard on the radio, a warning of snow by the end of the week, it just gets better and better but considering what the ukmo 00z looks like, it is not surprising.those movember whiskers will have frost on them by the weekend..haha

Edited November 26, 2012 by Frosty039

[Isolated Frost]

hi.can you put this in laymens terms as im not sure what were seeing here .thanks

The red is anomalous high pressure and the blue is anomalous low pressure- and the green lines is the wind flow at 500mb.

As you can see the red lines hit peak nr Svalbard/NE Greenland on both charts, which is conductive to a Greenland ridge into Svalbard and a still strong arctic high. You can the blue lines come into Britain on a NE/N flow on both charts, with a trough (lp system) nr us in France and the Benelux.

These simply indicate that though the Atlantic can push through any ridge- especially the one as weak as projected- we will still have blocking to the north and troughing to the south and east- meaning we are never far off cold even if the Atlantic does come back in.

The Scandi cold pool will widen substantially over the next few days- best to keep an eye on that.

[Gowon]

The BOM has trended colder as well and it looks very similar to the ECM - http://www.meteociel.fr/modeles/bome_cartes.php

[bluearmy]

Ian - you are probably rght to an extent re the pfj but i think it will be closer than you think - hence i tend to agree with dave

Also, those cpc charts were late last night which may well mean they were 'interfered with' by a forecaster.

[chris55]

Solid UKMO (again...) and a very cold one to by the looks of it.

ECM leaning more towards UKMO with the Canadian Low

GFS pushing energy through to the North

With UKMOs consistancy and the ECM leaning towards it i'd put my faith there as we stand this morning.

Exciting model watching!!!!! Will look forward to the 12zs.

[Polar Maritime]

Just heard on the radio, a warning of snow by the end of the week, it just gets better and better but considering what the ukmo 00z looks like, it is not surprising.

Yes Frosty, ukmo has stuck to it's guns, and looking at recent forecast's this seems to be the model they are leaning towards. Cold/snow is on the way, i can see another excellent week of watching coming up.

EDIT- Yes frosty ! some icy whiskers for some in the North Midlands

Edited November 26, 2012 by Polar Maritime

[bradymk]

GME higher resolution model which only goes out to t+72 is encouraging this morning, shows the low deeper and starting to move back westward. +t72 chart

[EML Network]

Spot the difference

[TAFKAP]

I think that is a very optimistic outlook Dave from where we sit this morning - the Azores High is already sat there and with the energy coming off Greenland it is only going to pull the jet North. If that happens we have no chance of staying on the cold side of the PFJ.

Good morning Ian, an interesting spin on things you have there. Could you please elaborate a little though? How is the Azores High going to affect the next few weeks and how long until the jet moves north? When do you think the switch to mild will be nailed on?

[Matty M]

ECM Ensembles a split.

probably 60.40 at T144hrs

probably 50.50 at T168hrs

[nick sussex]

You really couldn't make it up! Who writes these model scripts!

A big improvement by the ECM, the UKMO looks similar to yesterday although I think we're going to see some Atlantic energy cut se'wards past 144hrs.

The GFS decides its todays ECM with lots of energy spilling eastwards which that showed yesterday! All in all its a bit of a mess, I think whats appearing through the fog though is that pressure will probably remain high to the ne so we might see low pressure tracking se'wards could be some fun and games for you guys in the UK depending on the track of these.

[Duane S.]

So are we looking at a gradual cool down this week , a 2 day 'warm up' (and by warm I don't mean warm at all, just in relative terms) then the real thing from about one week today onwards? I think the models, in their own way, may be hinting at that.

[EML Network]

For me is seems clear, the ECM picked up on something yesterday, the JMA, GEM, NOCAPS all picked up on the same thing, the GFS was clearly not listening, at the bar trying to pick up a lady to take home for the night.

The GFS didn't get lucky at the bar so instead decided to concentrate on the weather, quickly realized it's 06z and 12z lacked some fundamental data, but by the time it realized and adjusted it was a case of too little too late.

Meanwhile the ECM , NOCAPS and possibly the JMA have all spent the night in discussing the new data, they have decided for the most part the new data was off...so have ditched most of it, but keeping some to throw into their outputs just to be on the safe side, the poor old GFS has been up all night playing 'catch up' with a dent in it's pride and a sore head.

Of course the wise owl that is the UKMO has seen it all before, sitting quietly by the open fire toking on a pipe and shaking his head

So I expect the 06z GFS will be a half hearted attempt to move slightly back towards where it was on yesterday's 06z and 12z ...and the saga continues

Edited November 26, 2012 by EML Network

[Alex]

I would hate to bang my own trumpet but I did warn people about the chances of this spell being short, the backtracking on the models of the longevity of this upcoming cold spell is hardly surprising with the stratosphere so cold, the PV will have little problems in re establishing under this ideal situation.

http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/html_e/pole30_n.html

The MJO is stil sat in its central core with little influence.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml

The blip in the northern hemispheric weather pattern can be put down to a sharp rise in angular momentum.

http://www.esrl.noaa.gov/psd/map/images/reanalysis/aam_total/gltotaam.sig.90day.gif

However my thoughts are still that it could become colder again towards the end of December, alot will depend on the stratosphere however with the MJO likely to move into phase 8 eventually, this is a sign of blocking.

[Jonan92]

Brazilian looks very interesting, it's a shame that it has no reliability

Edited November 26, 2012 by Jonan92

[Methuselah]

I'm not too sure that anything is really clear: that we have a range of solutions, ranging from one extreme to the other, ought to speak for itself, really?

[johnholmes]

Looking at the 500mb charts from NOAA shown by IF and the issue from ECMWF-GFS this morning. I am holding off making any predictions today as I want, as always, a couple of days data before deciding.

Yes the block in high latitudes is there but what is not there compared to their outputs 2-3 days ago is the pronounced ridge south of 60N giving a flow north of west into the UK. There is a tendency on all 3 over the past 24 hours to show a W'ly type of flow into the UK south of 60-65N. Nor is the previously pretty solid way in which all 3 dealt with the trough over and east of the UK helping to reinforce this pattern.

Like I've just said I am not giving a forecast just observing. The NAEFS for 00z is not yet available.

[Gibby]

Good morning. Here is the latest look at the 00zs from GFS, UKMO,GEM and ECM for today Monday November 26th 2012.

All models show a steadily improving picture after today as the last of a series of deep depressions moves slowly away from the East of the UK into Europe tomorrow. After heavy rain or showers today, particularly towards Northern England and North and West Wales a colder and fresher North wind brings brighter and drier weather to all areas for the rest of the week. There will be some sunshine for many but some showers too, wintry in the North and East. Many Southern and Western areas will become dry but with clear skies overnight frost will become widespread with patchy fog too for some, slow to clear in the mornings.

GFS then shows a ridge from the Azores High toppling SE over the UK over the weekend with dry and frosty conditions by night together with some fog patches. Early next week High pressure continues to the South of the UK with Low pressure to the North with a freshening and milder flow from the Atlantic arriving over all areas with rain at times, especially in the North. Later in the week a very deep depression brings gales and heavy rain to all areas followed by colder, windy weather with wintry showers. The end of FI shows very cold conditions with wintry showers and longer spells of rain, sleet and snow with the SW shown at risk of a transitory significant snow event at the end of the run as Low pressure pushes up from the SW.

The GFS Ensembles show a rather cold period to come before things become a little less cold on the final portion of the run. The operational was a cold outlier in the latter stages too. No deep cold is shown by any member nor any mild weather either. So just a period of somewhat chilly conditions with drier weather this week followed by somewhat more unsettled conditions next week with rain at times with some snow possible at times on the hills in the North.

The Jet Stream shows the flow having ridged North over the Atlantic moving South over the UK to Southern Europe where it turns East while later the flow breaks down with a Northern arm of the flow developing moving east into the UK in response to Low pressure developing near Iceland and Greenland.

UKMO for midnight on Sunday shows High pressure to the North while slack Low pressure covers the South in very light winds at the surface. The weather would be rather cold with some wintry showers near the coasts while many inland areas are more likely to be affected by frost and persistent and perhaps freezing fog. The odd shower could occur inland too with snow possible from any of these on the hills though amounts would likely be insignificant.

GEM shows the cold flow collapsing at the weekend as Low pressure pushes down from the NW with rain and snow on Northern hills before milder Atlantic air moves across from the West by the end of the run with rain at times.

ECM shows the North flow backing NW at the end of its run with the wintry showers in the North and East decreasing with time. Towards the West and South cloudy and drizzly weather looks likely as a slow moving front straddles the West which moves East early next week with milder conditions briefly followed by a cold and windy blast from the North for 24 hours or so when wintry showers would flood South. This then passes by Day 10 as winds back west with rather cloudy and damp conditions approaching West Britain again at the end of the run. The temperature gradient would be just a little below normal in the SW to rather cold conditions towards the NE.

In Summary today the models are beginning to lean away from anything significantly cold after this week. The weather will be rather cold and breezy for all this week with some wintry showers in the North and East but away from Northern and eastern coasts and hills much of the time will be dry and frosty by night. Next week it now looks like ECM might have had a good handle on this recently as some sort of breakthrough from the Atlantic looks increasingly likely. The transitions as always is likely to be very messy with various options shown as to how this situation develops. It does look unlikely though that there will be any significant wintry weather i.e snow anytime soon with conditions trending rather colder towards the NE while Southern and Western areas eventually see temperatures returning to nearer to normal values with some rain at times.

Don't forget my Model Analysis is available from up to an hour earlier on my website night and morning. Follow the link in my signature below.

[Paul]

Last I checked, this was the model thread, please can we keep it on topic - making weather forecasts based on whether a member has been online or not is definitely not what this thread is for!!

[Jonan92]

We will see in 10 minutes what path will follow the 6Z run

[weather eater]

Just read several pages of utter drivel, models discussed like a school boys crush, she love me, she loves me not. Synoptics evolve; they are not just born, stuck on to a page and then stay in stasis waiting for the day when they become real weather. These same conversations happen year after year but some people never learn. It’s simple really you can trust the models out to 72hrs most of the time however after that every passing day should be viewed with increasing amounts of scepticism. What the models show this morning is that the way forwards post 72hrs is far from settled and a number of people would be well advised to hold back on the, I told you so statements for the time being