Model Output Discussion

[sandstorm2]

This is similar to what i`m expecting early to mid Feb once the atlantic quietens down as it usually does in February.

http://www.wetterzentrale.de/pics/Rtavn3841.png

The atlantic just doesn't have enough power in it to take control of our weather with HP keeping a foothold over us throughout 18Z

Now that IS an easterly, not the watered down version that is currently being hyped up at the moment, unfortunately it is right out in the depths of FI.

SS2

[PB22]

And the T+120 FAX: http://www.meteociel.fr/ukmo/fax/fax120s.gif

Again, not too dis-similar to the 18Z GFS:

http://www.wzkarten.de/pics/Rtavn1141.html

And they have gone with their own model:

http://www.wzkarten.de/pics/Rukm1201.html

[cyclonic happiness]

Our local bbc forecast also says " a return to very cold weather for the whole of next week and there may even be some snow"

I think the model atm are just too willing to drive the Atlantic through, I think the meto are using alot more human imput to try and help the forecasts along.

I think the computer models maybe haven't had enough data to compete with a human in a cold spell such as this.

[January Snowstorm]

The atlantic just doesn't have enough power in it to take control of our weather with HP keeping a foothold over us throughout 18Z

Which was my point last night, high pressure over us will burn up the rest of Jan.

In fact it could bring us to the 2nd week of Feb

[nick sussex]

lets put the beeb into perspective. Helen Willets mentioned that the cold thats bottled up to our east will come across us early next week. we all know that. havent you seen the uppers moving east to west over the past few days on the nwp. she never mentioned any strength to the flow and she didnt speak beyond 'early part of next week'. sometimes i read thru the posts on here and wish i hadnt. its like bloody chinese whispers.

now back to the science - i see the 18z trying its hardest to build a greeny ridge but that damn block just wont leave us alone. ah well, FAXES due out soon

They've gone with their own model which isn't too much of a surprise given the ECM ensembles, I really hope the UKMO verifies as it's likely to give a few snowflakes down here! Overall though I'm quite encouraged by the trend in the models and wouldn't be surprised to see a stronger build of pressure near Greenland in the coming days.

[yamkin]

This is similar to what i`m expecting early to mid Feb once the atlantic quietens down as it usually does in February.

http://www.wetterzentrale.de/pics/Rtavn3841.png

The atlantic just doesn't have enough power in it to take control of our weather with HP keeping a foothold over us throughout 18Z

After what happened during the first week of February 2009, all eyes will be watching this with interest.

Edited January 22, 2010 by yamkin

[pottyprof]

I wonder where the MOD's have got to? Has Michael Fish summoned them to an Easterly tea party

It will be interesting to see the BBC forecasts over the weekend.

Lets just say that we hope that the BBC forecast will be discussed in the correct area of the forum. There have been quite a few OT posts removed and edited this evening. This will not continue. Please think before posting. One liners/off topic discussion will be plain old deleted if it carries on. The off topic posts just spoil this super discussion thread for everyone.

Come on peeps.. Keep it sweet..

[Guest North Sea Snow Convection]

The UKMO T+96 FAX chart: http://www.meteociel.../fax/fax96s.gif

Still a cold flow into the southeast, and not too dis-similar to the GFS 18Z for the same time:

http://www.wzkarten....s/Rtavn901.html

That echoes Kaddy on the latest BBC SE forecast. She has played down any SE region snow potential in sharp contrast to the lunchtime forecast - suggesting cold (1C for Tues) and dry. That is very much in line with the latest fax and, in view of the latest GFS, echoes pretty much all the models now out to midweek. Just posting that to put some clarity about the BBC/METO position on the easterly this evening.

What now needs further clarification is the evolution to the northerly late next week. GFS has taken another step forward towards the ECM tonight (from its earlier output) although there is some way to go yet.

Whatever happens, should there be a northerly, people should realise that this would be courtesy of an amplified atlantic ridge, and, unlike the first part of January, where there was underpinning from a sharply -AO and signficant high latitude blocking - it is unlikely to be anything more than a relatively transient feature (maybe 2 to 3 days perhaps though)

Edited January 22, 2010 by North Sea Snow Convection

[J10]

Latest Skiing Blog out now.

Also interesting to see the Met have gone with their own model out to T+120 Faxes,

[bluearmy]

actually - there is a good point above re the easterly at the end of fi - it wont happen but look at the date. 7th feb. when i was a nipper the best snowfalls happend mid feb. perspective please chaps, weeks of winter left yet.

Edited January 22, 2010 by bluearmy

[yamkin]

Lets just say that we hope that the BBC forecast will be discussed in the correct area of the forum. There have been quite a few OT posts removed and edited this evening. This will not continue. Please think before posting. One liners/off topic discussion will be plain old deleted if it carries on. The off topic posts just spoil this super discussion thread for everyone.

Come on peeps.. Keep it sweet..

Apologies pottyprof. After all the BBC posts, I thought a bit of humour might be needed.

On a serious note, GFS 18Z, GEM 12Z, JMA 12Z, GME 12Z, NOGAPS 12Z (18Z just coming out) are showing an Easterly along with the UKMO 12Z and fax. That includes the ECM 12Z too!

Edited January 22, 2010 by yamkin

[igloo]

Not chinese whispers - "Dan the man" corbett has been making quite a bit of this "easterly" and he is quite a trustworthy forecaster! - not one to over do something then! - we are only seeing cold temps and a slack flow - they seem to be seeing something more that's all

definitely seeing things i dont going by todays molel outputs looks fairly cold till midweek with a possibility of a easterly by midweek milder again anything after that is pure guess work

[LomondSnowstorm]

The UKMO don't have another longer range model, they use their own model and take alot of guidance from the ECM and its ensembles, together with the MOGREPS ensemble system upto 48hrs, perhaps people are reading too much into the bbc forecasts, perhaps they just mentioned the easterly and the cold might remain for a while with a slack flow with high pressure close by but even their own model sinks the block with the easterly gone by Wednesday. I'm all for ramping easterlies if this is justified but IMO its a red herring, any longer term wintry potential will have to come from the north with pressure building near Greenland, the easterly is a by product IMO of the models developing a different cold set up. Just as the pre Xmas cold spell downgraded the initial easterly as the models went in a different route to cold.

Sorry to be a bit pedantic but the pre-christmas easterly was not particularly bad at all for snowfall, with quite deep snowfall for quite a lot of eastern and southeastern Britain, with 6cm here, which is pretty good for only 24 hours. I have to agree though that the main thrust of that cold spell was from the northerly that followed, though in this instance the trough looks to be a bit further east, with the block just a bit too close to us to allow for troughs to move closer to us, though this may change in the coming days - http://www.cpc.noaa.gov/products/precip/CWlink/pna/nao.sprd2.gif A lot of uncertainty but quite a few models go for a fairly negative NAO for around the 1st February.

LS

[PB22]

Finally tonight, the ECM 12z ensembles for London:

http://www.meteogroup.co.uk/uk/home/weather/services/ensemble_forecast.html

The operational was one of the milder runs for later next week, which probably explains why the Met Office have gone with their own model on the FAX charts tonight. <_<

[Tom Montalbano]

What strikes me re. the latest fax at t96 is how weak it has the low NNE of Iceland, a little under 1000 mbs,

compare that to the GFS 18z at t90, under 968 mbs and 12z ECM, also around 968 mbs. Quite a marked difference at that range.

FAX. http://cache.netweather.tv/fax/PPVM89.png

GFS. http://charts.netweather.tv/gfsimages/gfs.20100122/18/90/h500slp.png

ECM. http://212.100.247.145/ecmimages/20100122/12/ecm500.096.png

Regards,

Tom.

[nick sussex]

The GEFS ensembles upto 180hrs show a quite unbelievable scatter at only 4 days out of 15c for London lowest 850 -10, highest

+ 5!

[Weather-history]

Finally tonight, the ECM 12z ensembles for London:

http://www.meteogroup.co.uk/uk/home/weather/services/ensemble_forecast.html

The operational was one of the milder runs for later next week, which probably explains why the Met Office have gone with their own model on the FAX charts tonight. <_<

Also notable how it then becomes one of the coldest member at the end which means the type of northerly shown by the op run is not really favoured by the ensembes

[bluearmy]

The GEFS ensembles upto 180hrs show a quite unbelievable scatter at only 4 days out of 15c for London lowest 850 -10, highest

+ 5!

much bette GEFS than for a while with more inclination to retrogress the blocking in the latter stages of the run.

[nick sussex]

much bette GEFS than for a while with more inclination to retrogress the blocking in the latter stages of the run.

Yes later on the trend is much better but earlier i don't think i've seen scatter like that at only 4 days out, even at this stage the short easterly still isn't certain but there looks a better chance for a northerly so not too bad at all.

[TEITS]

Apologies pottyprof. After all the BBC posts, I thought a bit of humour might be needed.

On a serious note, GFS 18Z, GEM 12Z, JMA 12Z, GME 12Z, NOGAPS 12Z (18Z just coming out) are showing an Easterly along with the UKMO 12Z and fax. That includes the ECM 12Z too!

Sorry Yamkin but none of these models really show an E,ly. I class a typical E,ly as snow showers, cold upper temps. What we have is the models showing a 24hr E,ly followed by a flow from the continent.

I haven't seen any BBC forecasts but from what I have heard they were suggesting snow showers next week. Well Unfortunately unless the models change the BBC forecasts will be different tomorrow morning as i've been saying all day!

Take for example the fax charts.

Monday. We might scrape a few wintry showers.

http://www.wetterzentrale.de/pics/brack2.gif

Tues. Dry and cold with rain spreading into NW Scotland.

http://www.wetterzentrale.de/pics/brack3.gif

Wed. Turning milder from the NW although still probably cold further S.

http://www.wetterzentrale.de/pics/brack4.gif

Sorry but all this stuff about secret models that we don't see is nonsense. We have access to the NAE which the BBC/Met O use. We also have access to the fax charts which obviously the BBC/Met O use. Beyond the forecasts are based on the UKMO/ECM ensembles.

This is why I said this morning that if the 12Z UKMO backs the GFS/ECM the fax charts will follow accordingly. I also said the BBC forecasts will change if the fax charts downgrade the E,ly. We can clearly see the fax charts for Tues/Wed are nothing special and neither will the forecasts on the BBC tomorrow morning if the fax charts remain unchanged.

Edited January 23, 2010 by THE EYE IN THE SKY

[kold weather]

Well the 18z ensembles are not actually too bad at all tonight overall in terms of the predicted evolution for he first week of Feb, esp compared to some other runs today.

What is very interesting to notice is how quite a few members now keep a split vortex which means our block shouldn't sink away into total oblivion. 12z ECM also has the vortex seperate upto 240hrs but by the end of the run its quite clear whats going to happen.

Gotta be said there are some very cold runs in those ensembles but not much reflection of that in the ECM ensembles.

[Duane S.]

I agree reference the comments made about the 'secret models' the MET use that we don't have access to. Yes I'm sure they have more info at hand but as TEITS says we have the access to the FAX and the high res NAE which are primarily reflections of their views based on all the latest computer model outputs. Ther are no 'super computer' model runs which take great precedence over the ones we can view. These guys have more experience and knowledge than 99.9% of posters on this forum and use it to good effect each time they create the FAX, NAE and METO further outlook.

Back to where we are now. A northerly has ALWAYS been the cards as the main event (strength and severity to be determined), the Easterly is only a transitional one that is required to get to the Northerly. Treat any benefits from it as a bonus I would say.

[cooling climate]

Absolute corker of a run from the ECM from t144 out to t192 so far with a very cold

and wintry outlook on the menu.

The ECM run this morning will certainly put a smile on many peoples faces this morning.

It really is a terrific run.

I wish the ECM run went past t240 hours as it would definitely show a very potent easterly

setting up I would have thought with a portion of the vortex cut off over Europe feeding

bitterly cold air over the UK.

The GFS is slowly, slowly coming on board, and the UKMO is three quarters of the way

there.

Edited January 23, 2010 by cooling climate

[Blizzardo]

Very good Northerly on this mornings ECM. More potent and longer lasting than previous runs.

[KTtom]

Pretty good agreement in the models this morning up to around +120. The initial northerly is sent into mainland europe, we have to wait for a secondary front to move south from southern Greenland before the northerlies start to take hold.

UKMO shows this feature @+144, GFS gives a half hearted northerly but the GFS is a corker as the scandi trough moves SW and the high manages to cling on to Southern Greenland.........as usual it will probably end up being a half way house

No easterly in sight now, so at least we can rule seaguls out as a forecasting tool.