Model Output Discussion:

[sandstorm2]

I like what 6z is saying until +120 but after that although amazing it is totally gone off the wall Crazy . A 980 deepening low over Northern England with -10 uppers and 60 MPH winds . 6z FI is near on impossible to develop like that so I suggest we just try and look to getting the initial pressure rise and Easterly and go from there .

Just wondering, but is that the low at +216, but you are right lets just hope that easterly materealises first.

SS2

[cooling climate]

IF the 06z is anywhere near correct in its evolution towards the much colder pattern

change don't be surprised to see the block or ridging take place a little further west

which would also bring the colder air in quicker.

I also think that the flow will be more suppressed because of the stronger heights to

the north which would show up on the ensembles as Aberdeen for example being on

the cold side of the ensembles.

[Eugene]

Whatever anyone thinks about the GFS it's still the best model at introducing trends

Yes i agree with this its the leader to be honest, yes it changes it's mind as all models do but it's the first to settle on the eventual near outcome IMO.

So which outcome are you leaning towards North Sea Snow Convection, you know which one i am inclined to

[TEITS]

GEFS mean at +120.

http://91.121.94.83/modeles/gens/run/gens-21-1-120.png?6

Another tug towards cold IMO.

[carnun]

it maybe the first to settle on a trend but it more often than not backtracks and falls in line with the ECM ouput. Speaking of which the ECM is having none of it.

[Guest North Sea Snow Convection]

Yes i agree with this its the leader to be honest, yes it changes it's mind as all models do but it's the first to settle on the eventual near outcome IMO.

So which outcome are you leaning towards North Sea Snow Convection, you know which one i am inclined to

My heart is obviously inclined full on towards the easterly.

My head says the same as most of this week - that the easterly is a good possibility, but that final model agreement has to take place first

[nick sussex]

Sorry I refuse to go down the GFS fantasy route,we've been here before and remember the GFS 18hrs run a few days back was wrong within T-72hrs so i'm certainly not buying any of this latest run. It's a leap of faith too far unless the ECM and UKMO back this tonight. The UKMO raw output would have to perform the mother of all backtracks to get anywhere close to this.

[Matty M]

Sorry I refuse to go down the GFS fantasy route,we've been here before and remember the GFS 18hrs run a few days back was wrong within T-72hrs so i'm certainly not buying any of this latest run. It's a leap of faith too far unless the ECM and UKMO back this tonight. The UKMO raw output would have to perform the mother of all backtracks to get anywhere close to this.

Important to remember around 50% of ECM members woul of backed something similar to this.

Its all about tiny small details.

[TEITS]

Sorry I refuse to go down the GFS fantasy route,we've been here before and remember the GFS 18hrs run a few days back was wrong within T-72hrs so i'm certainly not buying any of this latest run. It's a leap of faith too far unless the ECM and UKMO back this tonight. The UKMO raw output would have to perform the mother of all backtracks to get anywhere close to this.

I hear what your saying.

However like I said earlier Mondays UKMO/ECM 12Z was excellent and yet the 18Z GFS/GEFS mean was very poor. The next morning the UKMO/ECM 0Z trended towards the 18Z GFS.

Due to the changes occuring at +72 I really think we need to go with the latest model runs using the latest observational data. The 06Z GEFS have flipped massively towards an E,ly compared to the 0Z GEFS.

Im going to continue sitting on the fence until the 12Zs. However im extremely happy with the 06Z GFS and especially the GEFS mean.

[nick sussex]

well that settles it then. if the gfs is out on its own on this again it'll cave in like it nearly always does.

I'm not saying its impossible but we have to bear in mind that it doesn't have support yet and also take into account the GFS ability to go from one extreme to another between runs. I'll admit the trend today is better from most of the models as they generaly clear the shortwave se off the main trough without leaving residual energy behind, this is crucial, also the Norwegian trough which I've been obsessing over in here fills more quickly and allows a stronger ridge from the ne.

[Eugene]

Yes almost all ensemble runs now going for an easterly or southeasterly around T+120 hrs but this evolution starts as early as T+72 hrs :o

[nick sussex]

The crucial part of the output and really what opens up the route to cold is at 72hrs. If you look at the UKMO 00hrs for T-72hrs

http://www.meteociel.fr/modeles/ukmo2.php?nh=&ech=72&carte=1021

Then compare it to the GFS 06hrs run at 66hrs

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=66&mode=0

Notice the difference, how the UKMO leaves a trail of residual energy, this causes a pull like effect on the trough and brings this closer together with more energy later, this is why its absolutely crucial that theres a clean break by the shortwave se'wards.

This very small global difference magnifies down the line like a domino effect, tonight you'll know by this timeframe whether to reach for the prozac or not!

[Guest North Sea Snow Convection]

. It's a leap of faith too far unless the ECM and UKMO back this tonight. The UKMO raw output would have to perform the mother of all backtracks to get anywhere close to this.

Hello nick,

The output from the GFS as we go through next week and onwards is of course subject to a lot of questions about the usual GFS dreams and elaborations but I'm not sure that the UKMO does have to change much from t72 to fall in line with the initial evolvement to an easterly. There is little overall difference at that time betwen it and the GFS and in the circumstances and model volatility atm it is quite feasible for the changes required to happen. Of course it has to happen, in order to get to the desired outcome - and that is where as I say we need to get to the stage where the models agree that the block is in the ascendancy and that the atlantic troughs are kept at bay (or the lows undercut and allow the high to prevail).

But I don't think that in terms of the actual, shall we say mechanics of it all, that a very large backtrack is required at t96 and onwards by the UKMO. The ECM at t96 appears to show a good evolution to the easterly and it is only the usual t120 to t144 period where it comes more unstuck. And that is well into FI as we know.

Clearly ALL the models at some stage been over cooking that energy strength if we look at the modelling over the last few days. It is easy to forget that, with all the flip flopping around. The energy modelling from the GFS has been an enornmous turn around yet again overnight.

The UKMO has been far from bullet proof and has made enough miscalculations in both directions over the last few days. It overdid the expected jet energy at the weekend, and since then has been on/off with the easterly like the other models even if it has not exaggerated like the GFS

Edited February 3, 2010 by North Sea Snow Convection

[nick sussex]

Hello nick,

The output from the GFS as we go through next week and onwards is of course subject to a lot of questions about the usual GFS dreams and elaborations but I'm not sure that the UKMO does have to change much from t72 to fall in line with the initial evolvement to an easterly. There is little overall difference at that time betwen it and the GFS and in the circumstances and model volatility atm it is quite feasible for the changes required to happen. Of course it has to happen, in order to get to the desired outcome - and that is where as I say we need to get to the stage where the models agree that the block is in the ascendancy and that the atlantic troughs are kept at bay (or the lows undercut and allow the high to prevail).

But I don't think that in terms of the actual, shall we say mechanics of it all, that a very large backtrack is required at t96 and onwards by the UKMO. The ECM at t96 appears to show a good evolution to the easterly and it is only the usual t120 to t144 period where it comes more unstuck. And that is well into FI as we know.

Maybe I was overselling the backtrack! The UKMO needs to do what the GFS does with the shortwave and fill the Norwegian trough out quickly aswell. Of course I'm very happy to see these changes and hope that the GFS is right, I just think at this rate some members will be suffering from a stress related illness given the unbelievable model variability this last week!

Looking at the GEFS ensembles that must be the biggest change I've ever seen, if this was to verify it would IMO be the biggest backtrack of all time, or since we've had access to the models.

Edited February 3, 2010 by nick sussex

[karyo]

Yes almost all ensemble runs now going for an easterly or southeasterly around T+120 hrs but this evolution starts as early as T+72 hrs :o

Amazing turnaround in the ensembles: http://www.netweather.tv/index.cgi?action=ensviewer;sess=

However, the control doesn't want to know!

Karyo

[nick sussex]

Amazing turnaround in the ensembles: http://www.netweather.tv/index.cgi?action=ensviewer;sess=

However, the control doesn't want to know!

Karyo

Yes thats a bit of a worry but given the output depends on the behaviour of a shortwave and Norwegian trough filling the operationals higher resolution is more important seeing as thats within 120hrs, however its the GFS operational so an extra extra bit of caution needed!

[TEITS]

Really is an incredible change in the GEFS ensembles.

http://charts.netweather.tv/ensimages/ens.20100203/06/t850Cambridgeshire.png

Last time such a switch occured the following UKMO/ECM went the same way. Some members even bring in the E,ly even earlier.

Whilst we do need the UKMO/ECM to agree lets remember the Met O 3-5 day forecast does not resemble the UKMO/ECM/Fax charts.

[Guest North Sea Snow Convection]

Maybe I was overselling the backtrack! The UKMO needs to do what the GFS does with the shortwave and fill the Norwegian trough out quickly aswell. Of course I'm very happy to see these changes and hope that the GFS is right, I just think at this rate some members will be suffering from a stress related illness given the unbelievable model variability this last week!

Looking at the GEFS ensembles that must be the biggest change I've ever seen, if this was to verify it would IMO be the biggest backtrack of all time, or since we've had access to the models.

I do totally agree with you in regard to the need for model agreement. Something has to finally give with this but until it does then any outcome remains possible .

[Bobby]

This is getting ridiculous now, I've been watching the models for years and this is really taking the mickey. Also the biggest flip in the ensembles I've ever seen.

Improvement in the other models too.

No doubt they will all flip back to tropical SWlys again tonight. Pretty much impossible to make sense out of the models at the moment.

Edited February 3, 2010 by Barb-

[Eugene]

I have a feeling tonights T+72 hrs will be better than this mornings T+84 hrs fax, i`m sure the boys at the UKMO are already starting to sit up and take notice of the GFS and its ensembles, i reckon most of them favour its outcome to their own model if truth be told.

[shiver]

This is getting ridiculous now, I've been watching the models for years and this is really taking the mickey. Also the biggest flip in the ensembles I've ever seen.

Improvement in the other models too.

No doubt they will all flip back to tropical SWlys again tonight. Pretty much impossible to make sense out of the models at the moment.

same here i have never seen this before in the last 8 years once the modls flip they usualy stick to that outcome but this is different and for that reason im going with a very cold easterly outbreak

[MKN]

The ensembles are of little relevance really when one run they can all be in nearly perfect agreement of one outcome only for them to all be completely different from each other the next. However as you say, wet and windy would appear to be the most likely outcome at this stage.

looks like the point i was trying to make of the ensembles being able to flip from one scenario to another despite all of them agreeing on a certain outcome in the previous run looks bang on this morning. watch them all go for mild south westerlys on the 12z lol

[Frosty.]

Well the good news is that the GFS 06z does have support and it really is a great run, similar to the GEM 00z which was the pick of the 00z runs. I just heard John Hammond say we are just looking at a milder interlude up to the weekend with the chance of it turning colder next week so there could be growing agreement for some sort of cold blast from the east or north east developing through next week. :o

[Guest North Sea Snow Convection]

Well the good news is that the GFS 06z does have support and it really is a great run, similar to the GEM 00z which was the pick of the 00z runs. I just heard John Hammond say we are just looking at a milder interlude up to the weekend with the chance of it turning colder next week so there could be growing agreement for some sort of cold blast from the east or north east developing through next week.

Yes it is good to see that the GEM has changed its tune from last night.

The GFS ensembles for my area put the operational as one of the milder solutions. Many of them suggest -15 850's in about a weeks time! Don't you just love the GFS . Yesterday tea time they were about 15 degrees higher!

[Bobby]

I think the GFS may finally be onto something now, one of its big strengths I think is picking up details in these lows/shortwaves at short range and we're into just +72 now. UKMO and ECM are better at medium term trends but I'd inclinced to back GFS now, especially with such good ensemble support.