Model Output Discussion:

[alan snow]

My oh my, what a difference a day makes. I had lost all hope I must say on the Beasterly, well done to those who stuck to their guns, very brave indeed!

The ECM would produce lots and lots of cold and snow for the whole of the UK starting from next Monday, a strong Easterly wind would make it feel very cold and this would continue to the end of the run and into Friday, brrrrrrrrrr! Followed most probably by cold, dry and very crisp conditions for Skying up Shooters Hill a' la SM.

Interesting, If I remember right, back in December the same thing happened with that Easterly, GFS was all for it, particularly the "run du Parallel" which took over on the 15th, then it all disapeared only to come back again after a couple of runs with full agreement by all the models. I sincerely hope that after the recent rollercoaster of epic proportions that the ride might be finally over and that we can end up on a high!

ive tried skiing up shooters hill snowray its hard once past the water tower its much easier

[SMU]

That won't be necessary. The evolution is looking spot on. Its not about the easterly, its about the jet kicking south [and that will happen] and the block to N/NNW holding allowing NE'ly and then an easterly feed.

BFTP

Are we looking East now, I thought I was looking NW

S

[Duane S.]

.Basically there are so many variables to consider, the accuracy just goes out the window .No amount of sophisticated weather software ,no matter how advanced it is, can make an accurate assessment of weather patterns beyond a week,and that is being generous.

And in my opinion NEVER EVER will be able to for the reasons you stated. where we are presently is not far off as good as it is ever likely to get.

[waynetheweatherman]

Im no specialist on charts, very basic, however since all theyve shown the last few days of cold mild cold etc, im going to hold back untill things look a little more set.

I will say though it would be good to have one more 'fling' before winters out!

[Bobby]

And in my opinion NEVER EVER will be able to for the reasons you stated. where we are presently is not far off as good as it is ever likely to get.

True -chaos theory, tiny short term changes result in huge long term changes. There's diminishing returns also - you get less out of each increase of computing power than you did in the past, now enormous increases in computing power will result in only very minor improvements.

[nick sussex]

Good news from NOAA they've ditched the GFS 12hrs operational run because its an outlier and like the ECM and UKMO aswell as the GEM for events over there which is important regarding the Atlantic trough.

THE 12Z/01 DETERMINISTIC GFS WAS AN OUTLIER TO ITS ENSEMBLE

MEAN...AS WELL AS THE NEW GEM GLOBAL...UKMET...AND ECMWF...WITH

THE SUPPRESSED TRACK OF THE CYCLONE ALONG THE EAST COAST DAY 5.

And more good news.

BUT WITH ITS STRONG VERIFICATION THIS

SEASON...STUCK CLOSEST TO THE DETERMINISTIC ECMWF FOR THE DETAILS

OF THE PRELIMINARY UPDATE PACKAGE.

The GFS fall from grace continues!

Edited February 1, 2010 by nick sussex

[Frosty.]

After what the models did to us yesterday, some caution is required as the rampometer has gone off the scale again tonight with this latest ecm run, let's not get sucked in by charts @ T+168 hours although I admit the foundations would be in place well before that point. I love these latest charts as much as anyone else but it could all go horribly wrong and we know what trouble that causes on here.

[The PIT]

Good news from NOAA they've ditched the GFS 12hrs operational run because its an outlier and like the ECM and UKMO for events over there which is important regarding the Atlantic trough.

The GFS fall from grace continues!

LOL GFS was the bees knees a few days ago on here.

Can I find the discussion can I not.

Edited February 1, 2010 by The PIT

[Ben_Cambs]

Its very nice tonight to see UKMO and ECM agreeing at T+120. GFS has been isolated yet again and I wont be suprised if GFS backtracks a little tonight, although it probably wont backtrack fully on the 18z

[conor123]

Everyone ALWAYS turns against the chart's that show the mildest option on here in the winter and vice versa in the Summer.

It's slightly pointless that the same people that were insulting the ECM over mild South Westerlies 168hrs away the other day are now convinced of an easterly even further away!

There always seems to be an expectation that the Models showing the mildest outcomes will backtrack to bring 'the beast from the East'.

Edited February 1, 2010 by conor123

[Bobby]

The GFS fall from grace continues!

The only reason people so much attention to it because all the information is free. The ECMWF and UKMO are a cut above it and have been for a very long time.

In my opinion.

[nick sussex]

LOL GFS was the bees knees a few days ago on here.

Not by me I've always maintained the same line with the GFS, its too extreme and volatile and only good for zonal set ups. I was taken in by my favourite model the ECM but at least it had the good sense to follow the UKMO trend quite quickly, the GFS was totally useless!

The NOAA discussions in full are available here:

http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html

Edited February 1, 2010 by nick sussex

[KTtom]

I thought someone had posted that the ECM had performed worse out of the 'big 4' over six consecutive days?

There was a link, but I can't find it?

[Snowyowl9]

All I can is the block is back and a new trend is showing.

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

http://www.wzkarten.de/pics/Recm1201.gif

http://www.wzkarten.de/pics/Rjma1201.gif

http://www.wzkarten.de/pics/Rgem1201.gif

[The PIT]

Everyone ALWAYS turns against the chart's that show the mildest option on here in the winter and vice versa in the Summer.

It's slightly pointless that the same people that were insulting the ECM over mild South Westerlies 168hrs away the other day are now convinced of an easterly even further away!

There always seems to be an expectation that the Models showing the mildest outcomes will backtrack to bring 'the beast from the East'.

I call it model swapping. However I think they're being a bit cruel on the GFS as it basically does the same thing as the ecm at 120 to t140 which is high ridging north eastwards. After that it varies which I'd expect since we're getting well into FI land.

Remember the ECM has suddenly flipped again after showing mild conditions on the last few runs.

[aspire27]

Posted this yesterday:

Quote"From a newbie point of view this thread is becoming so hard to follow with regard to the model output. I remember a couple of days it was all about the

beast from the east now its all mild mild mild.

Makes me think some people need to calm down a bit. I bet we get a brilliant cold chart in the next few runs...then once again the beast is on!!"

I personally dont trust any output from the models with all the flip flopping all the time...

I think a lot of human input and experience is being used by the METO regarding their monthly forecast going for much colder conditions. If the models flip again

tomorrow which Id expect them to do, and the METO is still going for cold, im going with the METO for a cold period coming soon.

Edited February 1, 2010 by aspire27

[The PIT]

Not by me I've always maintained the same line with the GFS, its too extreme and volatile and only good for zonal set ups. I was taken in by my favourite model the ECM but at least it had the good sense to follow the UKMO trend quite quickly, the GFS was totally useless!

The NOAA discussions in full are available here:

http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html

Thanks for the link.

I know at one time they were getting the ECM people in too help with the gfs. Did that ever happen ????

[TEITS]

Everyone ALWAYS turns against the chart's that show the mildest option on here in the winter and vice versa in the Summer.

It's slightly pointless that the same people that were insulting the ECM over mild South Westerlies 168hrs away the other day are now convinced of an easterly even further away!

There always seems to be an expectation that the Models showing the mildest outcomes will backtrack to bring 'the beast from the East'.

I don't think many are convinced. If you read the posts you will see much of the discussion is about +96/+120 and how this might allow charts such as the ECM +168/+192 to become reality.

Getting a cold E,ly in the UK is all about having the right building blocks in the correct place. Now during the weekend the UKMO/ECM basically blasted the building blocks away like a bulldozer. However todays ECM/UKMO/GEM have shown these building blocks to reappear once again.

Who knows how this may pan out but its equally exciting and frustrating at the same time!

[nick sussex]

I thought someone had posted that the ECM had performed worse out of the 'big 4' over six consecutive days?

There was a link, but I can't find it?

Here you go.

http://www.emc.ncep.noaa.gov/gmb/STATS/html/acz6.html

Bear in mind the GFS verification stats won't include the easterly fiasco yet, expect its stats to nosedive in a few days, the UKMO could well be pushing the ECM very close in the top model stakes soon.The ECM over the last week has still been fine although all models have dipped slightly.

[shiver]

has anyone thought gfs was right all along in showing the easterly first if it comes off

[TEITS]

Not by me I've always maintained the same line with the GFS, its too extreme and volatile and only good for zonal set ups.

For me personally I find the GFS typically american i.e OTT.

When the model goes for an E,ly then it will show -20C uppers and 20ft snowdrifts. This extreme is also shown in zonal spells with low pressures often being too deep and resembling a hurricane. Having said this the ECM IMO can be rather biased towards blocking in F.I which is why at +120/+144 its quiet useful to look at the UKMO in these situations.

[nick sussex]

Thanks for the link.

I know at one time they were getting the ECM people in too help with the gfs. Did that ever happen ????

There was talk a while back regarding whether it was the data fed into the GFS rather than the actual model itself that was the problem, I'm trying to remember exactly here perhaps someone else remembers an experiment they did with feeding GFS data into the ECM or perhaps the other way round.

[billy]

I call it model swapping. However I think they're being a bit cruel on the GFS as it basically does the same thing as the ecm at 120 to t140 which is high ridging north eastwards. After that it varies which I'd expect since we're getting well into FI land.

Remember the ECM has suddenly flipped again after showing mild conditions on the last few runs.

I think thats true . The ecm has flipped from cold to mild and back again in the last 3 or 4 days and has been no worse than the GFS .The only model that has been REASONABLY consistent is the UKMO which IMO is the one we need to keep on board most of all. It seems that the ECM has been a bit erratic since its upgrade.

[NorthantsSnow]

I suppose the whole debate over GFS/ECM and which is better boils down to this-

1) When the ECM gets something incorrect, it quickly drops the idea and replaces it with another. The downside is it can often be very inconsistent from run to run, as we have witnessed over the past 24 hrs through the stark difference between the two 12z operationals either side.

2) When the GFS gets something incorrect on the other hand, it tends to be very stubborn and persists with the idea over multiple runs across several days, causing confidence to increase in its solution when often it is consistently wrong. It takes too long to pick up on new trends.

So as far as I'm concerned, the GFS is by far the weaker model as it is slower to respond to changes and is wrong more often than not. However the ECM cannot always be trusted either. And out to T144, the UKMO model is king.

[Jason T]

HI ALL, just to say what a change guessing tonights and tommorows runs are the ones now.