Cold Snap, T0-180Hours Only

doccy

They dish the GFS unmercifully on NW until it promises snow, and then all is forgiven and forgotten.

pistolpetes11

munsterlegend wrote: »

Why do met eireann rely primarily on the ECM? The gfs show the easterly reaching Ireland but its not reflected in their forecast.

Su was saying last week that they take a blend of 5 different models for there forecasting

They use the ECMWF, UKMO, DWD, Hirlam and Harmonie if I remember correctly

munsterlegend

pistolpetes11 wrote: »

Su was saying last week that they take a blend of 5 different models for there forecasting

They use the ECMWF, UKMO, DWD, Hirlam and Harmonie if I remember correctly

Any why not the Gfs if it can give some guidance? Seems to be a big hit on here!

Musicman2000

BEASTERLY wrote: »

Yes it is the most accurate of the medium term models, which is why i wont get excited until the ECM backs the GFS.

Have to agree, If the UKMO and Ecm agree its game over, Even if the GFS is putting us into the freezer.

doccy

munsterlegend wrote: »

Any why not the Gfs if it can give some guidance? Seems to be a big hit on here!

Under US law the charts are open to the public, whereas the ECM charge. That's why you see a lot of information on GFS charts on forums.

BEASTERLY

munsterlegend wrote: »

Any why not the Gfs if it can give some guidance? Seems to be a big hit on here!

Only because it's showing cold now! Few weeks ago the ECM was and the GFS said mild. Everyone on here was dishing it and saying it no good after 3 days out, and now look!

Irish Steve

pistolpetes11 wrote: »

A little video of how the GFS 6z and 12z evolved

The thought provoking aspect of both of those videos is the massive proportion of green and colder that's sloshing around in all directions, with incursions from the south on a regular basis.

Anyone that's going to stick their neck out and give definitive forecasts at the moment is very brave indeed, to say this is a knife edge situation is like comparing a surgeon's scalpel to a child's dinner knife:D

There are times when the difference between the cutting edge and the bleeding edge is nothing more than the pressure that's applied, and right now, I think we've seen 1060 Mb over Siberia? That sounds to me like significant pressure indeed

Moderating this for sure is going to be FUN:D

Dealing with some of the nervous breakdowns if it doesn't happen at 21:17 on a particular day with 2.7745 cms of dry snow from a wind direction of 093 degrees at 16.7 Kts ........... I think you know where I'm coming from.

Whatever, keep having fun, and congratulations on the promotion.

Tom Cruises Left Nut

Hmm, not really an outlier as was suspected !! :pac:



Or maybe it is in the later parts of the run !

Yahew

Both the control and op are outliers.

rc28

Yahew wrote: »

Both the control and op are outliers.

As far as I'm aware they are both at a higher resolution than the rest of the perturbations in the ensembles so it is seen as a good sign when the control agrees with the operational run.

nilhg

Re the various models and the differences, this is an interesting read, hopefully it's out of date at this stage but I wouldn't be surprised if it's not.


This bit might be relevant to the differences between the 0z/12z and 6z/18z

Look at model trends. If the low pressure moved east with this run, what did it do the run before that? For the GFS, look at a couple days of 00Z and 12Z runs for consistency. Avoid the 06Z and 18Z runs when 00 or 12 is available; in the U.S. these runs don't include the weather balloon network data (balloons are only sent up twice per day), and are therefore radically different and more likely to have bias.

darkman2

ECM is coming out now. Be surprised if this was not broadly similar to the UKMO as is normally the case but we'll see.

BEASTERLY

Oh dear...:(

nacho libre

munsterlegend wrote: »

Any why not the Gfs if it can give some guidance? Seems to be a big hit on here!

It's a us model and i suspect they don't feel as confident that it handles easterly evolutions as well as the european models do. there has been that suggestion in the past.

TheMilkyPirate

It was expected to be a mild outlier, But it's good to see the control run along with it.

pistolpetes11

BEASTERLY wrote: »

Oh dear...:(

Looking at the charts it has a low just blowing through the blocking high in FI alright, hopefully not a trend that continues

oterra

@ ffarrel
Sky News Alerts? Lets not jump the gun here...Vigilance methinks

BEASTERLY

pistolpetes11 wrote: »

Looking at the charts it has a low just blowing through the blocking high in FI alright, hopefully not a trend that continues

The ECM, GEM and NOGAPS have been showing this happening aswell.

pistolpetes11

Matthew Hugo @MattHugo81 Reply Retweet Favorite · Open
UKMO quite poor this evening but another stunning GFS Det run & ECM Det starting off very well as well! -

nacho libre

BEASTERLY wrote: »

The ECM, GEM and NOGAPS have been showing this happening aswell.

It's the way the UKMO outlook currently see it. Su campu mentioned a few days ago that he thought this is what would happen. He looks to have been spot on. There is the possibility of it not happening, but it really doesn't look good when there is a consensus between the three for this to happen. Hopefully some places will see snow before it does.

pistolpetes11

BEASTERLY wrote: »

The ECM, GEM and NOGAPS have been showing this happening aswell.

In Deep FI I wont get too worried , but the trend is not looking great for a prolonged cold spell,


Its similar to the great charts being posted last night from the GFS, the serious cold in FI again I would not be fully expecting them verify.

darkman2

Upgrade on the ECM at 96hrs




Very chilly continental flow at the surface. Bitter Siberian air racing westward. Good start, that's the main thing.

EDIT: Maybe we won't quite get exceptionally cold 850's this far west on this run but it is better then the 00z.

Tom Cruises Left Nut

Meteociel starting to grind to a halt again, must be a lot of snow bunnies on there !

oterra

darkman2 wrote: »

Upgrade on the ECM at 96hrs




Very chilly continental flow at the surface. Bitter Siberian air racing westward. Good start, that's the main thing.

Still progressing nicely at 120hrs

darkman2

oterra wrote: »

Still progressing nicely at 120hrs

I think this may represent the limit of progress on this run







Like I say it's better then the 00z and that's the main thing.

Tom Cruises Left Nut

Comparison at 144:


GFS +144





ECM +144

BEASTERLY

And the ECM once again goes with low heights trying to blow the western part of the high apart. I suspect this will be quite close to reality. Most models have that solution.

Luckily on this ECM run it fails somewhat and we do get a nice result out of it!

rc28

oterra wrote: »

Still progressing nicely at 120hrs

ECM looks a lot better to me than it's earlier 0z run. At +144hrs (next Friday) there is a pool of -8c upper air over the eastern half of Ireland and even a small pool of -10c air. Nice to see anyway even if it doesn't pan out that way

http://meteociel.fr/modeles/ecmwf.php?ech=144&mode=0&map=0&type=0&archive=0

pistolpetes11

BEASTERLY wrote: »

And the ECM once again goes with low heights trying to blow the western part of the high apart. I suspect this will be quite close to reality. Most models have that solution.

Luckily on this ECM run it fails somewhat and we do get a nice result out of it!

At what point would you now deem the charts to be in FI territory ?

Its getting had to keep up with them

ninebeanrows

Loooooooooooooooook at the cold pool:D:D