Model Output Discussion - 2nd March Onward

[bobbydog]

well.. i've been busy for a few days and not had much chance to look at the models. i've had a brief look now and again and laughed at the cold, snowy FI charts. however, it appears that, although the details are yet to be decided, the weather we have been searching for all winter, is possibly going to happen....... ironically, in spring!!

[johnholmes]

Just one question to you Dave. Do the fax charts have a human (met office) touch to them? Surely if they do they can't be that wrong....

yes they do

[johnholmes]

I think what would be interesting is to see what time the forecaster puts together those fax charts, what time does the UKMO forecaster see the ECM output and its ensembles.

Generally theres very rarely a big disagreement which starts at T72hrs so could it be that the forecaster does the fax chart quite early and then expects given the timeframes for the models to be close together. So doesn't really worry but in this instance the ECM and GFS disagree.

this link gives the times the charts are released by the senior man

http://www.weathercharts.org/ukmomslp.htm

[Ian Brown]

The FAX updates you see will have the chief forecasters input into them, IIRC they will review the UKMO Raw, ECM raw then the ensemble suites - if they all show uniformity then nothing will be modified, however if there is something in the RAW that is not so prevelent in the ens they will modify individual features to be less influential-

Are they ever wrong- yes as accurate as the data suite they are using....

ECM is a stunner tonight, & has moved to the GFS but then seperates quite quickly when it shows a sustained cold spell- whilst my opinion on the ECM is Clear - its numero uno I will wait & hedge my bets in this scenario-

Only the UKMo is the poor run tonight....

S

I think the UKMO is unlikely, but we know from past experience that North Easterlies are so hard to achieve. If the ECM had verified on numerous occasions this winter at T168-240 then there would have been many easterlies this winter.

[SMU]

http://www.knmi.nl/exp/pluim/Data/PLUIM_06260_NWT.png

Solid support for the operational- if anything the Mean perhaps slightly colder....

S

[Summer Sun]

ECM short ensemble

Good agreement on a cooler spell now

ECM full ensemble

Edited March 5, 2013 by Gavin.

[nick sussex]

The latest NAM 18hrs run continues to develop that shortwave south of Greenland.

Also if you look at the duty forecaster at NOAA the shortwave can be seen here right at the top ne corner at T 96hrs:

Of course things could change and the UKMO may still be right, it will be interesting to see what the UKMO do with the fax charts, I'd be surprised if they didn't modify their raw output.

It's unlikely we're going to see some big jump from T72hrs to T96hrs but perhaps a middle ground modification.

The irony here is that often we're hoping for shortwaves to not form but here we do need this to develop, if however the UKMO is right its not the end of the road, you can still develop colder conditions but its going to take longer and that just gives more time for another variable to appear.

Edited March 5, 2013 by nick sussex

[MR EXTREMES]

europe surely are going to break records considering the chart only goes down to -26 on the t850 to have this level of cold in winter is bad enough but spring surely could be the coldest spring for them in many years.

ukmo is on its own but i would not rule out what the upgrades have done could be that its right and we could be on the threshold of a warm spring so im still on the fence but in the words of ian brown WTF brrrrrrrr

europe surely are going to break records considering the chart only goes down to -26 on the t850 to have this level of cold in winter is bad enough but spring surely could be the coldest spring for them in many years.

ukmo is on its own but i would not rule out what the upgrades have done could be that its right and we could be on the threshold of a warm spring so im still on the fence but in the words of ian brown WTF brrrrrrrr

i wonder what our dutch friend thinks.....

[Carlrg]

Is there a reason that the purple pv is in the shape of a Jokers face. Irony i love it.

[CWT2012]

Surely the UKMO will admit they are wrong and fall into line with the ECM and GFS

[Bristawl Si]

Surely the UKMO will admit they are wrong and fall into line with the ECM and GFS

Maybe the ECM and GFS will be wrong.

As the forecast period hasnt happened yet how can any model be "wrong" at this stage for a period in the future?

[Methuselah]

Surely the UKMO will admit they are wrong and fall into line with the ECM and GFS

That's only if they are wrong?

[nick sussex]

Surely the UKMO will admit they are wrong and fall into line with the ECM and GFS

Regardless of what they do with the fax charts for some reason their raw output is going it alone. Until that changes then I'd be a little wary.

Given the timeframes tomorrow morning should surely decide this either way.

[Captain Shortwave]

Well we know the shortwave will develop from here for sure

Can GFS be wrong at T30

At T72 now, pretty much the same

Edited March 5, 2013 by Captain shortwave

[Snowman.]

Well we know the shortwave will develop from here for sure

Can GFS be wrong at T30

At the moment.

Any model can.

[MR EXTREMES]

18z looks good so far very good.

expect this to be another fairly clean run from the gfs.

here comes jack frost

[Carlrg]

At the moment.

Any model can.

I agree. On the new NAVGEM the shortwave looked like it was stalling the closer it came. It may not even get here, who knows?

Edited March 5, 2013 by Carlrg

[BLAST FROM THE PAST]

If the ECM verifies,the organizer's at Cheltenham will have to have a re-think!

Back in early December GP stated that his visit to Cheltenham may be cancelled....didn't realise he meant the Festival!!? What a Call...

ECM brings the cold in a touch quicker as thought, I want to see the UKMO jump on board....this winter has and will have a lingering effect due to its 'failure' to bring in full on easterlies.

BFTP

Edited March 6, 2013 by BLAST FROM THE PAST

[Ice Day]

-12 uppers into the east coast by Sunday lunchtime!

[Man With Beard]

Is the GFS trying to throw in a "mild" sector in the North Sea ... only the mild sector is under -8C at 850hPa?? Would be interesting for snow if it was.

[nick sussex]

So now you've got one model the UKMO that isn't interested upto 144hrs, the GFS is interested but then wants to push the high south, and the ECM has moved from zero to hero in the space of a day.

Just really sums up whats generally happened during the winter with the models going up and down the popularity stakes, hard to know whats going to happen at this point.

[Snowman.]

During sunday a front passing through will increasingly turn to heavy snow probably causing some dam slushy snow.

Taken a face value snow showers will begin to penetrate the NE.

This may seem nice but it isn't just passing through cold. I would also add that its slowly shifting south....

Try not to caught up next when chart are miles away. And think of all the correction there is going to be when we get closer to the time frame.

[Geordiesnow]

Just really sums up whats generally happened during the winter with the models going up and down the popularity stakes, hard to know whats going to happen at this point.

I think in general, the models has been projecting quite a large cold pool to head southwards from the Arctic into Scandi for days now, what the models have been toying with is how far South and East/West this massive cold pool will head and we seen some runs which shown Eastern Europe in the freezer yet the next run shown eastern Europe under warmer air!

I think there is hints it might turn colder this weekend but how quickly this happens remains to be seen, it depends how much of an undercut we see and whether we can get heights developing towards Greenland will decide if the UK taps into that cold air or not.

[nick sussex]

The latest NAE at T48hrs still doesn't want to know re the shortwave to the nw.So not the best of news after the GFS, so in reality the models can't even agree at T48hrs.

[Cheese Rice]

I'm 99% certain the UKMO is wrong.

A comparison with all the models at T144 shows the UKMO output is completely misguided.

X Model V UKMO T144

ECM

GEM

JMA

NOGAPS

GFS