Model Output Discussion

[aspire27]

The ECM ensembles show that the Operational was about the mildest run until deep into FI . Now on to the 18z .

Sorry could you put some more detail into that so a newbie can understand. I presume this means the latest ECM is on its own??

[andymusic]

Sorry could you put some more detail into that so a newbie can understand. I presume this means the latest ECM is on its own??

an outlier so on it's own - no support - so not likely to come about!

[aspire27]

an outlier so on it's own - no support - so not likely to come about!

Thank you.

So now looking to continue the theme on the GFS from earlier.

[Frosty.]

The ECM ensembles show that the Operational was about the mildest run until deep into FI . Now on to the 18z .

Still game on then, surely the ECM 00z won't be as ordinary as the 12z. The biggest turnaround today was by the ukmo from the poor T+144 on the 00z to the stunning 12z version. There are still several hurdles to overcome if we are to get another cold spell next week and the T+96 to 120 range is the crucial period.

[PubliusEnigma]

ECM Looks like it could bring in a south westerly at +192 ? GFS Looks good for cold ? ECM performed best last time round.

Hope i'm wrong.

Personally I dont think you can rely on ECM if its showing SW'lys . It never handles these things well this far out. I'm binning this run. For me the GFS seems to be the one who is nailing the most likely outcome for nextweeks cold snap. ECM is chopping and changing and the GFS has remained consistant over the last 36 hours, that must count for something. Besides this has to be a mild outlier as the GFS was also showing deep cold 24 hours ago, and was in line with the GFS.

[len]

The NAO/AO is a good tool for following where the models might go though, I find they pretty much follow the NAO/AO trend. 3 days ago the NAO/AO trend was followed by a GFS runs showing fairly deep cold and an easterly, since the NAO/AO has shown a neutral turn which the ECM may have picked up on. I'm not 100% sure how it works but it might have some bearing on the models runs, not necessarily the actual outcome.

I suppose it helps if the NAO/AO settles on a stable pattern.

Perhaps one of our more expert contributors could clarify something that was touched on a year or so ago?

I understood then, that the AO / NAO charts were just extractions from the models. They did not represent different sources/data/inputs. They are just a different way of looking at the same model outputs/data, but with reference to specific pressure distributions (Arctic/Iceland/Azores).

Many on here talk of them as if they are something separate, that might show something as yet hidden from the models.

Can someone qualified please clarify?

Len

[Cumulonimbus Tower]

Unfortunately theres quite a large difference in terms of the complexity of the pattern. The shortwave thrown off the main trough could become a real pain,

I was really looking at the 12z ECM compared with the 00 ECM and commenting that they were similar evolutions. The 12z aint much worse than the 00 imo. I can only view the 12z GEM out to 144h but to me the difference is basically the block further west which might actually bode well in the long run.

Edited January 19, 2010 by ned

[snowmadchrisuk]

Sorry could you put some more detail into that so a newbie can understand. I presume this means the latest ECM is on its own??

Yeah your pretty much Spot on , we don't get to see the ECM Ensembles in the same way we do GFS , but we get to see them for Temp , Precipitation and Wind. They are the same as the GFS Ensembles in the way that there are around 20 other members (Probably more im not sure on ECM) half are set positive the other half negative to initial data . We can then look at them and the more that go for a certain weather type makes it more likely that weather type will happen . Tonight The ECM Operational we saw Earlier was the mildlest run on Temps until right at the end of the run and then even at the end it is still above average . This all suggests that it is likely to be Colder than what the operational showed us.

Sorry if that is a bit rushed but I'm tired have had a long day .

Chris

Still game on then, surely the ECM 00z won't be as ordinary as the 12z. The biggest turnaround today was by the ukmo from the poor T+144 on the 00z to the stunning 12z version. There are still several hurdles to overcome if we are to get another cold spell next week and the T+96 to 120 range is the crucial period.

Yes I wish I could see the 850's for that UKMO chart. I read on a hurricane website that the UKMET has seen a 12% Improvement in it's verification status due to upgrades.

[len]

I don't know why some on here are talking about real cold arriving.

I've been watching it. (surface cold even).

It's taken two days to get from East Poland to Cental Poland http://www.uni-koeln.de/math-nat-fak/geomet/meteo/winfos/euisoTTPPWW.gif

Even if it was programed to head this way (which it isn't) it would take another twelve days to get here at this rate!

[snowmadchrisuk]

Perhaps one of our more expert contributors could clarify something that was touched on a year or so ago?

I understood then, that the AO / NAO charts were just extractions from the models. They did not represent different sources/data/inputs. They are just a different way of looking at the same model outputs/data, but with reference to specific pressure distributions (Arctic/Iceland/Azores).

Many on here talk of them as if they are something separate, that might show something as yet hidden from the models.

Can someone qualified please clarify?

Len

John Holmes put this Information from NOAA into the Netweather Guides if that is any help .

Specific ENSO, AO, NAO information is not fed into the numerical

models. However, one could say that since each of these indices is a

reflection of the state of the atmosphere and oceans, and the current

state of the atmosphere and oceans (pressure, temperature, winds, etc.)

is known to the models through their initialization, then the models

do know a bit about what the indices are attempting to quantify.

[nick sussex]

Perhaps one of our more expert contributors could clarify something that was touched on a year or so ago?

I understood then, that the AO / NAO charts were just extractions from the models. They did not represent different sources/data/inputs. They are just a different way of looking at the same model outputs/data, but with reference to specific pressure distributions (Arctic/Iceland/Azores).

Many on here talk of them as if they are something separate, that might show something as yet hidden from the models.

Can someone qualified please clarify?

Len

Thats correct so its best to look at other teleconnections to give a better idea of the general trend, however they are of some use in that they give an idea whether the operational and the ensembles are reflecting the expected state of for example the northern hemisphere. Sometimes models can be slow to pick up on things equally they can over react, with any switches in output its always best to wait for the model to settle down before drawing too many conclusions.

[snowmadchrisuk]

I don't know why some on here are talking about real cold arriving.

I've been watching it. (surface cold even).

It's taken two days to get from East Poland to Cental Poland http://www.uni-koeln.de/math-nat-fak/geomet/meteo/winfos/euisoTTPPWW.gif

Even if it was programed to head this way (which it isn't) it would take another twelve days to get here at this rate!

I think these days in the UK , People class -10 850's as real cold , and if we draw a straight Easterly that would be very much on the cards .

Edited January 19, 2010 by snowmadchrisuk

[chionomaniac]

Perhaps one of our more expert contributors could clarify something that was touched on a year or so ago?

I understood then, that the AO / NAO charts were just extractions from the models. They did not represent different sources/data/inputs. They are just a different way of looking at the same model outputs/data, but with reference to specific pressure distributions (Arctic/Iceland/Azores).

Many on here talk of them as if they are something separate, that might show something as yet hidden from the models.

Can someone qualified please clarify?

Len

Len,

You are right. The NAO and AO do not have any control on the models or atmosphere at all. They are merely indices that show the pressure differentials away from the average between the corresponding areas. For example the -AO that we have seen for a lot of the winter is a result of higher pressure over the Arctic during this period not the cause of it.

c

[bluearmy]

Len,

You are right. The NAO and AO do not have any control on the models or atmosphere at all. They are merely indices that show the pressure differentials away from the average between the corresponding areas. For example the -AO that we have seen for a lot of the winter is a result of higher pressure over the Arctic during this period not the cause of it.

c

i think len's point is that the ao/nao forecasts are simply a reflection of the GFS/GEFS output. i expect that they probably are. if the ens are wrong then the forecasts are also likely to be wrong.

[Mr_Pessimistic]

hi people, maybee a bit off topic? but I was just wondering, is there any new model predicting systems (such as ECM, GFS) being programmed/created currently, or are the current ones just updated when possible or when new data types/technology become available?

thanks.. .

[damianslaw]

ECM seems to be doing its occassional flip flopping with regards to longer term synoptics,fully expect to flip flop back to a colder scenario tomorrow in line with GFS and UKMO who I believe are picking up on the right trend i.e. those heights to the east will be advancing our way again after a temporary retreat on Friday all helped by the ridging of heights out of the azores behind the front that is going to come crashing through on Thursday evening and into Friday.

Not going to make any comments for next week other than cold rather mild, how cold too early to say.

[Ben_Cambs]

I note that GFS 18z seems better than 12z, some colder uppers (-8C and below) reach Britain and the run is more fludic than 12z

[Snowyowl9]

I think these days in the UK , People class -10 850's as real cold , and if we draw a straight Easterly that would be very much on the cards .

This was real cold last winter,it was one of the coldest days here anyway and a few snow grains.

http://www.wetterzentrale.de/archive/ra/2009/Rrea00120090101.gif

http://www.wetterzentrale.de/archive/ra/2009/Rrea00220090101.gif

Nothing like a good inversion.

[snowmadchrisuk]

I note that GFS 18z seems better than 12z, some colder uppers (-8C and below) reach Britain and the run is more fludic than 12z

This is a much better run , because the block remains stronger to the East , Still 1050mb +168

[Shiny_Bottom_1]

an outlier so on it's own - no support - so not likely to come about!

As the information was for a newbie, I would just like to correct this.

The ECM Op is one of the milder runs, up until about Monday next week (varying on days). It however is not an outlier, and has clear support for the same time frame from the control run.

In fact, for tomorrow it has support from most of the other members, only a few on Thursday (op is a milder member), and then most of the members again on Friday. It is from Saturday is loses the majority support, but again the control run is quite parallel to the operational run. But they do all go for something similar by around Tuesday.

However, if you are looking for cold, from Saturday onwards, more and more of the ECM members go for colder temps (for the Netherlands just to point out, in case your were wondering where they were based too).

Edited January 19, 2010 by Shiny_Bottom_1

[cooling climate]

Ugly synoptics on the 18z GFS run. As I said earlier sinking highs don't cut it for me.

Mind you it is novel I suppose a cold spell coming via Greece.

This looks to be a trend this evening though lets see where we are in the morning.

[nick sussex]

The latest fax chart for 120hrs looks similar to the ukmo raw output and hasn't been modified towards the ECM so obviously the UKMO have looked at the ECM ensembles and don't think theres much support for the ECM operational run.

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

[Snowyowl9]

Ugly synoptics on the 18z GFS run. As I said earlier sinking highs don't cut it for me.

Mind you it is novel I suppose a cold spell coming via Greece.

This looks to be a trend this evening though lets see where we are in the morning.

I would call them perfect charts for

http://91.121.93.17/pics/Rtavn1681.png

http://91.121.93.17/pics/Rtavn16817.png

Edited January 19, 2010 by Snowyowl9

[nick sussex]

In terms of the eventual sinking of the Siberian block this would be likely, however this is expected in conjuntion with troughing developing over Scandi basically splitting high pressure with a cell retrogressing westwards into the Atlantic, as long as pressure remains low in the Med this reduces the chances of milder conditions and then we have to wait and see whether WAA in the western Atlantic will build pressure into Greenland sending the amplified jet south over Scandi with a chance of a nw or northerly, this is all well into the later timeframe. Lets just see if we can get this initial easterly sorted out.

[PB22]

Interesting model output again tonight, and its hard to to see where this will all end up. The ECM London ensembles will be interesting viewing in a bit, but I remain very sceptical of any true deep cold pool affecting the UK in the next week to ten days. Having said that, it does look like temperatures at the surface will often be on the cold side, and we could see a number of dull and cold days as we sit in no man's land. To me, tonight's T+96 and T+120 FAX charts suggest this:

http://www.meteociel.fr/ukmo/fax/fax96s.gif

http://www.meteociel.fr/ukmo/fax/fax120s.gif