LET IT SNOW AND BE COLD!!!***RAMPING THREAD***Mod Note #1193#2705

maquiladora

omicron wrote: »

Having read all the hype here, I'm finding it hard to understand where it's coming from. There is not one chart from 0-120 hrs on the latest ECM/UKMO/GFS (op&control)/GEM showing uppers colder than -8, and -6 are rare and very brief. There is no low level snow evident in any reliable timeframe - so why is there so much talk about snow?!

Uppers change a lot from run to run in the near term let alone days ahead. I think the excitement is more about potential beyond 120.

Also if you look at the archives for the big snow events, most of them have what look like marginal uppers.

compsys

Jaffusmaximus wrote: »

You obviously don't agree? Those charts all seem quite similar to what the GFS was showing a few days ago before it suddenly backtracked and pushed all the cold further East with ease.

You'd just like to see the cold far more entrenched further West for us.

Lucreto

Can someone provide a quick summery of whats happening. It is too late to read 20 pages.:D

Would it be correct to say chances of snow on Sunday are now low but next week has the same chance of snow we had during the past week for this weekend.

I don't think it makes sense what I just said too tired.:o

maquiladora

compsys wrote: »

You obviously don't agree? Those charts all seem quite similar to what the GFS was showing a few days ago before it suddenly backtracked and pushed all the cold further East with ease.

You'd just like to see the cold far more entrenched further West for us.

It's a start, things were looking very grim with the GFS up until this evening. It felt like game over to me this morning, now we have a chance.

omicron

Oarrack Bama wrote: »

We don't need -8 850's for snow. That's a myth. We could get snow in -3 given correct variables in other regards. Sunday looking good it really is.:)

We don't need them but it's damn near impossible get low level lying snow without them. Given all the current data, I can't see where you're pulling this Sunday forecast from, no chance of lying snow at low levels on current charts.

Oarrack Bama

omicron wrote: »

We don't need them but it's damn near impossible get low level lying snow without them. Given all the current data, I can't see where you're pulling this Sunday forecast from, no chance of lying snow at low levels on current charts.

The variables are just about right for the moment. Dew points and theta values are below minimum criteria - temperatures at or just below freezing. Result on high resolution GFS Sunday as a front meets these conditions.

maquiladora

omicron wrote: »

We don't need them but it's damn near impossible get low level lying snow without them. Given all the current data, I can't see where you're pulling this Sunday forecast from, no chance of lying snow at low levels on current charts.

Certainly possible in the northeast on the GFS anyway. -7 uppers there, I'd think you'd see snow there if that came off. Might not be widespread but its possible.

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2013/01/10/basis18/ukuk/t850/13011306_2_1018.gif

whitebriar

omicron wrote: »

We don't need them but it's damn near impossible get low level lying snow without them. Given all the current data, I can't see where you're pulling this Sunday forecast from, no chance of lying snow at low levels on current charts.

-8 850's are important but it snowed in the east during the 2010 spell at times with even -2 850's as we had our own cold pool.
In simple terms,if the surface feed is cold enough,snow formed high up does not melt if it has no above freezing layer to fall through.


Really low 850's are important for decent lake effect convection though.

Oarrack Bama

whitebriar wrote: »

Really low 850's are important for decent lake effect convection though.

Spot on. Differential between SST and upper air temperature can have literally explosive consequences.;)

omicron

whitebriar wrote: »

-8 850's are important but it snowed in the east during the 2010 spell at times with even -2 850's as we had our own cold pool.
In simple terms,if the surface feed is cold enough,snow formed high up does not melt if it has no above freezing layer to fall through.


Really low 850's are important for decent lake effect convection though.

Realistically, we won't have a cold pool on Sunday though. The north east has a slight chance, but I can't see it happening in the midlands or east. The 528 dam line ( which generally wouldn't even be enough for snow) only barely touches the north and east for a while on Sunday.

I honestly hope I'm wrong on this or that we get a short term upgrade though!

maquiladora

omicron wrote: »

Realistically, we won't have a cold pool on Sunday though. The north east has a slight chance, but I can't see it happening in the midlands or east. The 528 dam line ( which generally wouldn't even be enough for snow) only barely touches the north and east for a while on Sunday.

I honestly hope I'm wrong on this or that we get a short term upgrade though!

If there is snow somewhere on Sunday it will be a bonus, but certainly not the main event that most people are looking for. The real potential is hopefully after that.

whitebriar

omicron wrote: »

Realistically, we won't have a cold pool on Sunday though. The north east has a slight chance, but I can't see it happening in the midlands or east. The 528 dam line ( which generally wouldn't even be enough for snow) only barely touches the north and east for a while on Sunday.

I honestly hope I'm wrong on this or that we get a short term upgrade though!

Do you know,it should be cold enough,for populated higher ground above 600ft in for example inland wicklow or north and west wexford,higher parts of Dublin etc and obviously the North east,so hard to be definitive with such model flux

Oarrack Bama

whitebriar wrote: »

Do you know,it should be cold enough,for populated higher ground above 600ft in for example inland wicklow or north and west wexford,higher parts of Dublin etc and obviously the North east,so hard to be definitive with such model flux

Too conservative. Dew points negative, wind off shore absolutely crucial;)

Pa ElGrande

Eastcoastryan

Well the GFS 0z looks to have taken another step back, UKMO doesn't look very inspiring either but again there doesn't seem to be any consistency! :rolleyes:

maquiladora

Not liking the 0Z runs this morning. It's looking more difficult to get enough of a block to our north. Very messy. Concerned for the ECM.

Eastcoastryan

maquiladora wrote: »

Not liking the 0Z runs this morning. It's looking more difficult to get enough of a block to our north. Very messy. Concerned for the ECM.

ECM looking better out to 120 to my untrained eye! -8 uppers of East of Ireland

Looks even better at 144... Wakey Wakey Everyone!!!

whitebriar

Eastcoastryan wrote: »

ECM looking better out to 120 to my untrained eye! -8 uppers of East of Ireland

oh the ecm is a beaut so far if you like a trend towards snow,do you like snow?

Eastcoastryan

whitebriar wrote: »

oh the ecm is a beaut so far if you like a trend towards snow,do you like snow?

Just a little... Have you ever seen models disagree like this in the past WB?

whitebriar

Eastcoastryan wrote: »

Just a little... Have you ever seen models disagree like this in the past WB?

Nope!

force eleven

Met E forecasting an uninspiring weekend of weather. A let down after the possibilities earlier in the week. Interesting that its Friday and their outlook which is normally up to a week ahead, stops at Monday. They aren't exactly sticking their publicly funded necks out?!

Ares

What would be the result of the chart?



Apocalyptic snow across Eastern and Central Europe?

Larbre34

force eleven wrote: »

Met E forecasting an uninspiring weekend of weather. A let down after the possibilities earlier in the week. Interesting that its Friday and their outlook which is normally up to a week ahead, stops at Monday. They aren't exactly sticking their publicly funded necks out?!

they stuck them out twice since sunday and had their heads chopped off. The position they are taking now is much more appropriate. No weather service can call this with confidence so they are holding position. 36-48hrs notice of any likely severe event would be sufficient

edit: theyve just changed the outlook to 'beyond tuesday the forecast is very uncertain'. Id give huge credit to the duty officer for that, its absolutely the case and at worst it will encourage the public to keep in touch with the forecast. They are clearly addressing the foolish flim flamming that went on with them chasing the ECM around the dancefloor earlier this week

maquiladora

Well the 0Z ECM is the best model of the morning, no doubt about it.

It does topples the high, but not until FI, so no need to worry about that at this point.

Very different from recent ECM runs from 120 onwards.

The magical mystery rollercoaster rides on.

maquiladora

force eleven wrote: »

Met E forecasting an uninspiring weekend of weather. A let down after the possibilities earlier in the week. Interesting that its Friday and their outlook which is normally up to a week ahead, stops at Monday. They aren't exactly sticking their publicly funded necks out?!

People were moaning about Met Eireann doing an outlook too far ahead because of how it was changing due to the models changing.

Now Met Eireann are not forecasting too far ahead and people are complaining because of that.

:rolleyes:

The best supercomputers in the world are strugging to figure out whats going to happen 4 days from now.

Speak Now

Met Eireann sum it up perfectly IMO, "Beyond Tuesday the forecast is very uncertain". Models are barely holding up for 3/4 days out at the moment.

DOCARCH

232 viewing at 0740.....somethings afoot!

Tom Cruises Left Nut

maquiladora wrote: »

Well the 0Z ECM is the best model of the morning, no doubt about it.

It does topples the high, but not until FI, so no need to worry about that at this point.

Very different from recent ECM runs from 120 onwards.

The magical mystery rollercoaster rides on.

I...dopn't...know...if...I...can...do...this...anymore :pac:

Tom Cruises Left Nut

Uppers from the 00z NAE for Sat



DPs



2m Temps

Larbre34

I think MTs update has injected some much needed reality about the track we're on - heading in the right direction but in the short term only mixed precip and some snow at elevations, although could be a taster for events within a few weeks.

I for one wont be torturing myself with 6 hour ly ups and downs on the 5 day progs. The trend remains our friend.