This Week's Storms - FORECAST, MODEL DISCUSSION ONLY

JanuarySnowstor

Hmmm not only does the ECM weaken Thursday's event it actually disappears lol

Iancar29

Weathercheck wrote: »

ECM not keen on developing storm2!!!!

Possible mistake and recaps on next run?

I remember seeing the same thing for the Carmen storm with one of the models last year. 2 days out and it didnt develop it at all on one of the runs then showed up again on the next

rc28

So, as expected, the downgrades are taking place or is this just an outlier?

ninebeanrows

rc28 wrote: »

So, as expected, the downgrades are taking place or is this just an outlier?

we will see in the morning, or maybe have an indication when we see the Ensembles suite.

Redsunset

Weathercheck wrote: »

ECM not keen on developing storm2!!!!

Harps

Very odd run there, every model run for the past 3 days shows an intense storm then suddenly it totally disappears. hard to believe they've been getting it that wrong all week?

ME still showing a major storm on the forecast just now as well..

Updrage for Tuesday's storm as well in the north west

dsmythy

ECM is such a buzzkill.

maquiladora

Will have to check ecm ensembles to see if the op has support, if it does then check the 0z gfs/ukmo to see if they move towards the ecm, if they do, then it may be the start of a big downgrade but its impossible to know yet.

Picking out one run of one model proves nothing until we see support from ensembles and the other major models.

Tom Cruises Left Nut

It looks like the ECM may have had 1 too many Christmas tipples !

irish1967

Ah well that's it then. Can we close the thread now ?

M.T. Cranium

Radical change on ECM may be unreliable as it follows from developments at 72h of strong secondary trough rotating around Tuesday event. By the way the storm does not disappear, we're looking at 24h snapshots, in between there would be a 980 mb low racing east across southern parts of Ireland and south-central England. Some strong winds might remain with that postulated feature. However, as stated above, I find the evolution suspect when all other models are holding firm and not developing the mid-week secondary feature very strongly.

On the other hand, the ECM has the best verification stats, although really all the models are within a few per cent, so when one is vastly different from the others, you have to wonder why.

maquiladora

How is the 12Z gem and nogaps? Any other model showing something like the ecm? I cant check them here.

Rougies

After that latest ECM .. I can picture howlinwolf right now trying to unban himself to tell us "told ya so"




Here's the 12z NOGAPS maq, GEM not out yet...

Nabber

Quite a downgrade. In fact if it were any other prediction system the programmers would be looking for the bug.

NOt all models agree tho

nacho libre

Harps wrote: »

Very odd run there, every model run for the past 3 days shows an intense storm then suddenly it totally disappears. hard to believe they've been getting it that wrong all week?

ME still showing a major storm on the forecast just now as well..

bear in mind their forecast is usually based on the previous model run.

Harps

M.T. Cranium wrote: »

Radical change on ECM may be unreliable as it follows from developments at 72h of strong secondary trough rotating around Tuesday event. By the way the storm does not disappear, we're looking at 24h snapshots, in between there would be a 980 mb low racing east across southern parts of Ireland and south-central England. Some strong winds might remain with that postulated feature. However, as stated above, I find the evolution suspect when all other models are holding firm and not developing the mid-week secondary feature very strongly.

On the other hand, the ECM has the best verification stats, although really all the models are within a few per cent, so when one is vastly different from the others, you have to wonder why.

It passes well to the south though so mainly France and southern England that get hit, we seem to get nothing more than a breeze

ECM wind gust at 102h



Ensembles and the 12z gfs will be interesting later

Tom Cruises Left Nut

Ensembles link for later if anyone needs them

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_temperature_at_850hpa!168!pop!od!enfo!enplot!2009112700!!/

maquiladora

If I remember right, the ecm was the first model to show Tuesdays low less severe so worth keeping that in mind now with this.

ECM ensemble mean will be important later.

corkman123

haha...so all this excitement for nothing??? :mad:

Kippure

With things changing so fast maybe the models are now starting to find it difficult to work out what roughly will happen. Simon Keeling makes a good point about the "maybe" Atlantic high trying to link towards greenland.

http://www.youtube.com/watch?v=6J8DxTNG5PM&feature=channel_video_title

ninebeanrows

maquiladora wrote: »

If I remember right, the ecm was the first model to show Tuesdays low less severe so worth keeping that in mind now with this.

ECM ensemble mean will be important later.

I don't remember Tuesday's low being much more intense than this?

I think people saw a chart similar to this and thought it was extreme, but then we went and looked at the windspeeds and saw that the jet wasn't that strong over us and the gust speeds weren't that extreme.

But it wasn't much dissimilar to this.

nacho libre

corkman123 wrote: »

haha...so all this excitement for nothing??? :mad:

if other models agree with the ecmwf, then yes. the ecmwf has signifcantly downgraded previous storms, only for the other models to follow suit. however this run could still be a hiccup.

maquiladora

All we can say for sure is that the 12z ecm is out on its own showing something very different to all the other 12z models, as well as different to its own previous runs.

Only time will tell if this was a wobble or a trendsetter. We'll probably know in the morin!

leahyl

Oh no hope this isn't the beginning of a downgrade already!

Irish Steve

Solyad wrote: »

I don't normally do the "will it snow/rain/gale in my town" but I've to fly out of Dublin airport Thursday morning and back (from London) Friday evening so I'll put it this way... What level of storm does it take to disrupt Dublin airport typically. I've searched online and found a reference to a two hour closure due to 60mph cross winds in October but if thursday/Fridays storm hits the way it looks would it even be open?

This is looking tricky. IF it happens to the degree that the models are suggesting, anything smaller than a 737 is ideally going to have been moved out of harm's way to another airport that's out of the range of this, as winds of these speeds and gusts of higher are close to the "lift speed" of the wings, and stopping the aircraft moving in these strength winds becomes a severe problem, it requires a very large empty space around the aircraft so that if it weathercocks, it doesn't hit anything else and do damage. That sort of spare space no longer exists at Dublin.

The larger aircraft can also be affected in several ways. There are door opening speed limits, to avoid the risk of a door being damaged by being caught in a gust, and to avoid the risk of injury to crew members that may get dragged out of an opening that has no steps below it, or be hit by a door that they've lost control of when closing it.

Automatic air stairs such as on the 737-800 have an operating limit in wind speed, though I don't know what it is, as I never handled 800's, and the older traditional steps, especially on larger aircraft such as A330's or 767 and the like are seriously dangerous in high winds, especially when being moved around the place.

Even large aircraft can be badly blown around by gusts, and if they are on an airbridge, or have stairs close to them, that can do serious damage.

Loading and unloading bulk containers of bags is also risky in high winds as some containers are not particularly heavy, and the loading platform can be 30 Ft above ground, with nothing to restrain the containers on the platform other than gravity.

Landing and take off in severe gusts can also be "challenging", or worse, depending on the gust strength, and Dublin is particularly more exciting when the winds are strong from a South Westerly direction due to the effect of the Wicklow Hills, the last few miles in to Runway 28 can be challenging at best and downright uncomfortable or worse.

I don't know what the wind restrictions on airbridges are, but Thursday has the potential to exceed it.

In a nutshell, if this comes about to the degree that it seems to be suggesting, Dublin is likely to be severely disrupted, and Belfast, Cork & Shannon will also be having a bad day.

The best I can suggest right now will be to keep an eye on what's being forecast, and if this storm is not significantly downgraded, contact the airline to see what their opinion is on Wednesday.

None of the above allows for any additional possible disruption if either of these storms drags in any significant quantities of Snow, which is also now being suggested, so realistically, be prepared for the trip to not happen,

Sorry if that sounds overly pessimistic, but I have both flown and done ground handling work in bad conditions, and it's not much fun doing either of them.

Steve

cherryghost

Meanwhile, latest run has increased snow accumulation on Wednesday

whiteandlight

Can we please stop saying "I knew it", "Its going to downgrade" etc etc and actually discuss what the models are showing be it good/bad/indifferent? It has made this thread frustrating to read.

Birdnuts

People shouldn't lose the head over this - the storm is still there, its just a bit further South on this run, chances are that ECM will move it further North over subsequent runs

nacho libre

Enderman wrote: »

Meanwhile, latest run has increased snow accumulation on Wednesday

yeah the wetbulb temperature looks good. we should definitely get snow on Tuesday and Wednesday if it stays at that.

M.T. Cranium

Have to say on reflection I am very dubious about the ECM downgrade, as the other models have much faster development of the storm at 72h and much depends on model performance over the sector from central North America to the central Atlantic, one place where the ECM does not have a demonstrated edge (in fact on American forums there have been extensive questions raised about recent changes to ECM model input and subsequent 2011 performance). So it would not surprise me to find later that there is a return to the plan A for the ECM and no changes on the other models.

Not that the 18z GFS is always the best indication of anything, but I guess that's our next clue, there is no 18z GEM except for their 48h regional which might at least tell me something about developments in the central Atlantic as a slight clue.

Just one other note before I head out for a while (it's a lovely day here) -- the incoming storm has been somewhat lost in the shuffle here and it is more than just a minor deal, especially in terms of the cold squally conditions likely to follow in its wake. So we still have that on the go.