Cold Spell Media Forecasts and Model Output (General Chat)

ninebeanrows · 16-12-2010 12:28am #1

All media forecast discussion, general model output discussion and questions in here please.:)

H2UMrsRobinson · 16-12-2010 12:37am

Ok I'll get it going - M2 Buoy has not updated since one o'clock today - any ideas why or does it do this from time to time.

largepants · 16-12-2010 12:38am

I hope I'm in the right place. I noticed that big bank of cloud heading our direction form the nnw. Am I right in saying the wind is blowing ssw for it to reach Ireland? And if so is there a potential for the wind to change and for this to miss us altogether?

Obviously I realise that nothing is 100% at this stage but going on previous experience is there a chance this might happen?

I'm new to all this so forgive my ignorance.

rilz · 16-12-2010 1:12am

Here comes the cold front into Northern Scotland on latest radar!

http://yfrog.com/g4coldfrontp

thetonynator · 16-12-2010 1:29am

H2UMrsRobinson wrote: »

Ok I'll get it going - M2 Buoy has not updated since one o'clock today - any ideas why or does it do this from time to time.

is the m4 reporting? It will be the first sign of the front approaching. . .can't check i'm on mobile. .

Cionád · 16-12-2010 1:31am

thetonynator wrote: »

is the m4 reporting? It will be the first sign of the front approaching. . .can't check i'm on mobile. .

Yes, at 11pm

Temp 10.5
DP 7.0

Tropical

pistolpetes11 · 16-12-2010 1:33am

thetonynator wrote: »

is the m4 reporting? It will be the first sign of the front approaching. . .can't check i'm on mobile. .

yep it is

M4
62093 16 Dec
0:00 1031.0 270 24 10.3 7.0 80 n/a -9.9 10.3

alfa beta · 16-12-2010 1:33am

Cionád wrote: »

Yes, at 11pm

Temp 10.5
DP 7.0

Tropical

wonder when it'll hit those dizzy heights again after tomorrow?!

Mayo Exile · 16-12-2010 1:33am

thetonynator wrote: »

is the m4 reporting? It will be the first sign of the front approaching. . .can't check i'm on mobile. .

M4 at 2300: Temp 10.5. Dewpoint 7.0. It's in for a hell of a shock come tomorrow.........!!

sdanseo · 16-12-2010 1:33am

Anyone just see the late forecast?

I think I'm in love with Evelyn.

leahyl · 16-12-2010 1:40am

sdonn wrote: »

Anyone just see the late forecast?

I think I'm in love with Evelyn.

Did she say anything different to the one at 9.30?

thetonynator · 16-12-2010 1:43am

Thanks for that report guys. . Reckon air temps over sea could fall below 0?! :P brrr. . . :P

TheMilkyPirate · 16-12-2010 1:45am

leahyl wrote: »

Did she say anything different to the one at 9.30?

Nope

Irish Steve · 16-12-2010 1:58am

leahyl wrote: »

Did she say anything different to the one at 9.30?

Debateable

She certainly rowed back from the "possible warmer spell before christmas" that got a mention earlier, so I'm assuming their latest models have scotched that idea.

Words like significant, disruption, SNOW, accumulations, cold, and the like were a lot more in evidence than they have been even earlier in the day. While not quite hitting the panic button yet, there is certainly a clear indication of unpleasant weather in the mix for the next 5 days.

Steve

sdanseo · 16-12-2010 2:10am

She was quite clear that it looked "likely to remain cold right up until Christmas".

force eleven · 16-12-2010 2:13am

I really hate posting these charts, but just felt I had too. Saturday Morning....

littlefriend · 16-12-2010 2:15am

@force eleven - is that real? Any for Friday night?

force eleven · 16-12-2010 2:18am

littlefriend wrote: »

@force eleven - is that real? Any for Friday night?

Yes, its Weatheronlines GFS interpretation. They really should be taken with a pinch of salt, but they sure look nice, and they give at least an idea of whats coming, early Saturday onwards.;)

rilz · 16-12-2010 2:25am

I think the wrap around force will be Southern Ireland - (Dublin included) - The Midlands up to NE England and South Scotland.
Heaviest precip in these parts on Sat.

Harps · 16-12-2010 2:53am

http://news.bbc.co.uk/weather/forecast/10094

Friday night looks nice

lucernarian · 16-12-2010 3:30am

The models are really showing some excellent potential for Friday night almost nationwide. On an imby note I feel that Louth could miss out by a squeak. Just as well I'm living in Dublin these days! Now I think GFS has gone a little crazy with the LP development. I am struggling to see how explosive cyclogenesis is going to take place, especially with a track that crosses through much of Ireland, then Wales and England. But certainly, a heavy fall (perhaps 6-8 inches in parts of Leinster) is being suggested by the models, with the added problem of stronger winds in more southern counties. Inland parts of Co. Cork could see classic blizzard conditions for a while, though snowfall may be short and sweet further south.

Now here's the part where I pee on the parade: I don't see much model support for continued heavy precipitation over Sunday and Monday over almost any part of Ireland! The positioning of this LP clearly isn't nailed as it only cropped up over this afternoon but it suggests only slack northerly winds over Ireland once the system passes over Ireland on Saturday morning.

The UKMO forecast has a more plausible progression, with more sensible precipitation and pressure charts. It also keeps the threat of snow showers for at least Leinster and northern Donegal over more of Saturday. Even with that, I fear MT Cranium's snow predictions will be somewhat overdone except in Ulster and parts of the western seaboard.

EDIT: The ECMWF and GME are also frankly crazy for Friday night and is much more supportive for snowy conditions over Sunday and Monday. All hope is not lost yet. For basic pressure charts, the ECM and UKMO have a bit of an edge in my opinion, so perhaps I should have more faith:D

And I find it interesting that the ECM's progression after Sunday differs quite differently from the GFS and UKMO models. What to make of it all...

nacho libre · 16-12-2010 3:46am

since the lp only popped up this afternoon,you can't rule out further shallow lows developing, or troughs crossing Ireland during the weekend. i think therefore it's plausible that some places in Ireland may see snow beyond Saturday. also there could be a significant snowfall from a breakdown attempt as we go in to the early days of next week.

rilz · 16-12-2010 4:06am

Showing perfectly on radar as the cold front pushes South.
Backedge snow already in Scotland.

http://yfrog.com/2gcoldfront1p

lucernarian · 16-12-2010 4:10am

Yes, potential is there for next week. Just what that will be is very much up for discussion with model disagreement rampant. I'm happy to see that the ECMWF is better for snowy stuff for the first half of next week, as the GFS always likes to toy around with an Atlantic breakdown and I'm not so sure it's realistic.

My main thoughts behind Sunday are that there isn't much organised ppn forecast. Winds are also predicted to be reasonably slack over Sunday.

rilz · 16-12-2010 6:08am

This is our cold front on doorstep!

http://yfrog.com/g0polar1p

See those showers packing in behind it - All snow!

sdanseo · 16-12-2010 6:17am

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=54&code=0&mode=2

Showing a snow risk over Ireland constantly through to Tuesday (Mardi) - specifically on the east coast. Dunno how reliable that is though.

rilz · 16-12-2010 6:49am

The cold front is touchin on N Ire door.

http://yfrog.com/giv1111111111p

M.T. Cranium · 16-12-2010 7:55am

Forecast time. Just a few quick thoughts.

The models all staying on their somewhat separate tracks, it would seem. I will have to blend and develop by intuition a little bit, however, have decided to keep the general themes from yesterday's update.

The front is going to sweep in very quickly now, but I've just spotted what looks like a weak polar low in the northwest flow around 59N 15W heading straight for northwest Ireland. This may arrive this evening at the pace of the jet stream (100 knot winds at 500 mb south of Iceland).

Winds at the Faeroes are exceptionally strong, just checked 06z and they were gusting above 70 knots on hilltops there.

I suspect that as dramatic as the models may look now, they could be struggling with the sheer power of this regime change, and that developments over the weekend may ramp up rather than down. With the PV apparently set to sweep southwest across Ireland, and exceptionally cold uppers in place, it makes sense to be on the alert for greater development of meso-scale features; the models have a deceptive look of sudden calm and weak wind fields that may prove misleading to some extent.

dak · 16-12-2010 9:20am

RTE Radio one froecast 8am.....snow may accumulate on the ground......have no idea where else it could accumulate !

wildefalcon · 16-12-2010 9:23am

Forgive the ignorance, but does "meso-scale" mean a serious winter event?

Thank you.

dak · 16-12-2010 9:25am

wildefalcon wrote: »

Forgive the ignorance, but does "meso-scale" mean a serious winter event?

Thank you.

Wikipedia!

Mesoscale meteorology is the study of weather systems smaller than synoptic scale systems but larger than microscale and storm-scale cumulus systems. Horizontal dimensions generally range from around 5 kilometers to several hundred kilometers. Examples of mesoscale weather systems are sea breezes, squall lines, and mesoscale convective complexes.
Vertical velocity often equals or exceeds horizontal velocities in mesoscale meteorological systems due to nonhydrostatic processes such as buoyant acceleration of a rising thermal or acceleration through a narrow mountain pass.

wildefalcon · 16-12-2010 9:34am

dak wrote: »

Wikipedia!

Mesoscale meteorology is the study of weather systems smaller than synoptic scale systems but larger than microscale and storm-scale cumulus systems. Horizontal dimensions generally range from around 5 kilometers to several hundred kilometers. Examples of mesoscale weather systems are sea breezes, squall lines, and mesoscale convective complexes.
Vertical velocity often equals or exceeds horizontal velocities in mesoscale meteorological systems due to nonhydrostatic processes such as buoyant acceleration of a rising thermal or acceleration through a narrow mountain pass.

Thanks! So, that means it's big, yes? Serious winter event.

dak · 16-12-2010 9:56am

I think the Mesoscale Model uses archived upper level atmospheric data to extrapolate wind speeds to ground level for any given height!

wildefalcon · 16-12-2010 10:32am

dak wrote: »

I think the Mesoscale Model uses archived upper level atmospheric data to extrapolate wind speeds to ground level for any given height!

and an excerpt from MT Craniums earlier post:

"it makes sense to be on the alert for greater development of meso-scale features; the models have a deceptive look of sudden calm and weak wind fields that may prove misleading to some extent. "

Does this mean the cold "up there" will come down here, because there isn't much happening down here.

Wasn't there a movie about that? Lots of Snow, and people from the US fleeing across the border to Mexico?

Thank goodness this thread allows "general chat", as my mind wanders in mad directions.

Villain · 16-12-2010 10:56am

So now we have seen the dreaded downgrades, 18z ain't call the pub for no reason.

maquiladora · 16-12-2010 11:16am

Villain wrote: »

So now we have seen the dreaded downgrades, 18z ain't call the pub for no reason.

A downgrade of some sort was inevitable after that. There couldn't really have been much more of an upgrade.

thetonynator · 16-12-2010 11:17am

Villain wrote: »

So now we have seen the dreaded downgrades, 18z ain't call the pub for no reason.

what happened in the 6z or is it out yet?

JeanLucPicard · 16-12-2010 11:52am

Im confused...

I have to travel from Wexford to Dublin on Friday evening....will this be possible?

Is the Wexford town area likely to get the predicted heavy accumulations of snow forecasted?

I cant read maps or charts so hopefully someone in the know can help me out.

Thanks everone

JeanLucPicard · 16-12-2010 11:53am

Wasn't there a movie about that? Lots of Snow, and people from the US fleeing across the border to Mexico?

[/QUOTE]

That movie was The Day After Tomorrow I think!!

Villain · 16-12-2010 11:57am

I wouldn't try and forecast anything beyond 12 hours at this stage charts are changing hugely on every run. Its wait and see I'm afraid

nacho libre · 16-12-2010 12:22pm

Villain wrote: »

I wouldn't try and forecast anything beyond 12 hours at this stage charts are changing hugely on every run. Its wait and see I'm afraid

exactly
the bottom line is don't take any run too seriously. you could end up with an ulcer otherwise!

cherryghost · 16-12-2010 12:29pm

I'll say again what I said yesterday. The charts won't ever give 100% accuracy. For a more stable reading, wait until tonight, things will be more set in stone.

Although the weekends features seems like a downgrade, don't let your guard down. It's still some serious stuff that's predicted, especially over Friday night/Saturday.

davehey79 · 16-12-2010 12:59pm

cherryghost wrote: »

I'll say again what I said yesterday. The charts won't ever give 100% accuracy. For a more stable reading, wait until tonight, things will be more set in stone.

Although the weekends features seems like a downgrade, don't let your guard down. It's still some serious stuff that's predicted, especially over Friday night/Saturday.

do you still think Longford will get some of the snow this time round?

cherryghost · 16-12-2010 1:03pm

davehey79 wrote: »

do you still think Longford will get some of the snow this time round?

A definite yes. If not tonight, then tomorrow and tomorrow night

davehey79 · 16-12-2010 1:06pm

cherryghost wrote: »

A definite yes. If not tonight, then tomorrow and tomorrow night

best news i heard all day

thanks cherryghost

th3 s1aught3r · 16-12-2010 1:34pm

North Wales has a servere snow warning. Do you think that would make its way to our east coast or is it travelling straight down?

snaps · 16-12-2010 1:37pm

th3 s1aught3r wrote: »

North Wales has a servere snow warning. Do you think that would make its way to our east coast or is it travelling straight down?

No because its only NW facing coasts that will get the percip.

maquiladora · 16-12-2010 2:08pm

Forgot about this thread!

Warnings

Weather Warning

Issued at 16 December 2010 - 11:19
Update on Severe Weather
Very cold wintry weather will start today and will continue into next week with ice by day and by night.
Snow showers developing this afternoon and continuing tonight and Friday morning. These falling mainly over Ulster and Connacht initially, but some showers will reach parts of west Munster, the Midlands and north Leinster later.
Total accumulations up to Friday lunchtime
5 to 10 cm over Ulster, and Connacht, worst on high ground, with possibly some drifting, but totals of 2-5 cm elsewhere.

A second more significant snow event is expected to occur during Friday afternoon, Friday night and for a time on Saturday. A band of heavy snow is expected to spread across the country from the west and northwest.
Further totals of 10-15cm possible, with all areas at risk.

National Forecast

16 December 2010 11:37

Today

Cold and windy this afternoon with temperatures continuing to fall. Some dry bright spells, but showers also. These will turn wintry in the North and West, with snow in places.
Tonight

Very cold and icy tonight with occasional snow showers. These most frequent over the north and west, with some drifting possible on high ground. The snow showers will be scattered elsewhere. Lowest temperatures zero to -3 degrees and feeling colder in the brisk northerly wind.

Tomorrow

Very cold and wintry again tomorrow with further snow showers, mainly over Ulster, Connacht and west Munster, but some dry bright spells too. Later in the day, a band of more persistent snow will reach the West before spreading countrywide. It will be bitterly cold, top temperatures zero to +3 degrees at best, but feeling colder in the fresh northwesterly wind.

http://www.met.ie/forecasts/

cherryghost · 16-12-2010 2:32pm

These charts are going to change in a few hours for sure. Not only is there a low forming and heading SE towards us as we speak, theres a new low forming in Eastern England.

This may result in Fridays snow front moving across the country slower than expected, and maybe hanging further west than this mornings charts are indicating

Not · 16-12-2010 2:35pm

maquiladora wrote: »

A second more significant snow event is expected to occur ...

http://www.met.ie/forecasts/

Not like them to use such terminology.

Looks like their official meterological forecasting speak is starting to be influenced, I wonder where from ?:D

ninebeanrows · 16-12-2010 2:37pm

cherryghost wrote: »

These charts are going to change in a few hours for sure. Not only is there a low forming and heading SE towards us as we speak, theres a new low forming in Eastern England.

This may result in Fridays snow front moving across the country slower than expected, and maybe hanging further west than this mornings charts are indicating

Where are these developments you talk of?

Cold Spell Media Forecasts and Model Output (General Chat)

Comments