National: Cold spell Charts/ Media/ Forecasts (Strictly no chit-chat) (15/12/2010)

nacho libre

Please keep chic-chat to the other thread.




look at that beauty! bone chilling upper atmosphere wind straight from the arctic freezer! we are talking polar low territory and active troughs crossing down over us!

feel free to edit this mods as you see fit.

WolfeIRE

latest GFS extending lifetime of the upcoming cold spell into christmas.

Snow risk remains for anywhere in Ireland from Thursday into Tuesday

TheMilkyPirate

T+186 on the latest GFS has a potent low over the south of ireland moving up and away to our east on wednesday next, Fantasy island i know but that would surely fall as sleet/snow given the temp charts for the same timeframe? Precip looks very heavy.

nacho libre

personally i think this chart maybe slightly conservative. i think parts of Ulster could have 4-6 inches of lying snow by Saturday afternoon.

snaps

If im not asking a stupid question, what do the different colours mean in that 1st chart?

WolfeIRE

wind speed snaps

Tom Cruises Left Nut

snaps wrote: »

If im not asking a stupid question, what do the different colours mean in that 1st chart?

I may be wrong but I think speeds ?

darkman2

WRT Friday - there is an increasing risk of more significant snowfall across the country during the day. Looks like a frontal trough may move through. On the down side the mild sector will be close to the South coast so things look sleety there. But could be appreciable snow elsewhere. Have to be watched.

irishmotorist

snaps wrote: »

If im not asking a stupid question, what do the different colours mean in that 1st chart?

I'm still trying to figure out the general themes of the charts, but usually there's a legend of some description on the charts. In this one, the title at the top of the chart is "Wind speed/direction" at 850hpa (not sure myself yet what this bit means) and the side has the colour coding.

I've seen a good few references to 850hpa in the threads here over the last while. It sounds like it's a pressure, but is it related to altitude or anything?

Iancar29

irishmotorist wrote: »

I'm still trying to figure out the general themes of the charts, but usually there's a legend of some description on the charts. In this one, the title at the top of the chart is "Wind speed/direction" at 850hpa (not sure myself yet what this bit means) and the side has the colour coding.

I've seen a good few references to 850hpa in the threads here over the last while. It sounds like it's a pressure, but is it related to altitude or anything?

Ye its relative to 1 mile or so above the surface.

whiteandlight

Iancar29 wrote: »

Ye its relative to 1 mile or so above the surface.

Thanks. Ive wOndered that too. It'll be my new thing learnt today!

irishmotorist

Iancar29 wrote: »

Ye its relative to 1 mile or so above the surface.

Without wanting a training session in all this (as I plan to get some books and learn a bit more myself), is there a law or rule of thumb that says how this relates to ground level? If this is a 2 semester answer, I can go digging myself rather than bogging here down...

eoinbergin

Hey guys last week i had a link to a great wind model which showed the progression over a couple of days and i cant seem to find it. I looked through the helpful links section but to no avail. Does anyone here have a good links that are not in the thread on links thanks

WolfeIRE

eoinbergin wrote: »

Hey guys last week i had a link to a great wind model which showed the progression over a couple of days and i cant seem to find it. I looked through the helpful links section but to no avail. Does anyone here have a good links that are not in the thread on links thanks

http://magicseaweed.com/msw-surf-charts2.php?chart=1&res=750&type=wind&starttime

http://www.xcweather.co.uk/

nacho libre

a chart to savour!

the 510 dam line that close by is incredible!!

we could have a prolonged spell of snow moving down across the country based on this chart. i also think unexpected features could well pop up over the weekend. so i feel it's reasonable to say most places in Ireland will have seen at least a bit of snow by Sunday! well i don't want to jinx things but we are getting into reliable timeframe now!

cian1500ww

I asked this in the other thread but I think it got lost in all the posts, how is this shaping up in comparison to the event that we had around this time last year?? I remember seeing the heaviest snow of my life exactly one year ago this coming Sunday.

hotwhiskey

Just take a look above Iceland it has just came into view looks impressive.

http://www.sat24.com/Region.aspx?country=eu&sat=ir&type=loop

th3 s1aught3r

hotwhiskey wrote: »

Just take a look above Iceland it has just came into view looks impressive.

http://www.sat24.com/Region.aspx?country=eu&sat=ir&type=loop

Is that the Greenland express?
I assume its going to come down and push that Atlantic front out of the way?

Brenireland

hotwhiskey wrote: »

Just take a look above Iceland it has just came into view looks impressive.

http://www.sat24.com/Region.aspx?country=eu&sat=ir&type=loop

Cheers for that looking good,moving fairly lively.... early tomorrow evening one would imagine we may see the floodgates open?...

mickger844posts

Friday looking great for the whole country bar the south west where it could be marginal with Dew points hovering around zero but still probably ok.

Tom Cruises Left Nut

mickger844posts wrote: »

Friday looking great for the whole country bar the south west where it could be marginal with Dew points hovering around zero but still probably ok.

Inquitus

When it says say 2-4mm of snow, am I correct in thinking that translates into a few inches as its describing the depth as if it fell as rain?

darkman2

ECM going for a heavy period of snowfall across the country on Friday similar to the GFS. You can make out the warm sector off the South coast - spot on like the GFS.

DOCARCH

Inquitus wrote: »

When it says say 2-4mm of snow, am I correct in thinking that translates into a few inches as its describing the depth as if it fell as rain?

1mm is approx. = 1cm of snow.

qwert2

I don't mean to be a snow kill joy, but I think we're in for a lot of cold weather and maybe not too much snow? I could be wrong. Does anyone think we're talking 1982 levels here?

darkman2

qwert2 wrote: »

I don't mean to be a snow kill joy, but I think we're in for a lot of cold weather and maybe not too much snow? I could be wrong. Does anyone think we're talking 1982 levels here?

No, in a word:)

ninebeanrows

Netweather will go into meltdown after the ECM 96hr chart!

Shows snowstorm over London!

mickger844posts

Looking at the speed of the Greenland Express is it due to hit the country a little early ???

TheMilkyPirate

qwert2 wrote: »

I don't mean to be a snow kill joy, but I think we're in for a lot of cold weather and maybe not too much snow? I could be wrong. Does anyone think we're talking 1982 levels here?

I hear this thrown around quite a bit, more so in the last few days. 1982 was an extreme event in ireland while it's possible (likely?) that something like that will happen again i don't think it will be this weekend. But then again i don't really know what i'm talking about as i'm only 22 so wasn't around and only have basic weather knowledge :pac:

darkman2

Weathercheck wrote: »

Netweather will go into meltdown after the ECM 96hr chart!

Shows snowstorm over London!

Not only London - the (occluded probrably) front trails back over Ireland. And that after a prolonged period of snow on Friday.




And more troughing from the South on Sunday




That's 3 days of potential more prolonged snowfall. Interesting.

maiden

Whats are the lowest temps to expect?

darkman2

ECM 144hrs which is Monday







Weathercheck must be having palpatations at this stage:D

If that came off we would be looking at very low daytime maximum temperatures.

JanuarySnowstor

Where do you see the troughs darkman ?
Also how do you know the occluded front is draped back over Ireland ?

To me, albeit great charts, I wonder has the potential shifted East to UK leaving us drier after Friday

darkman2

JanuarySnowstor wrote: »

Where do you see the troughs darkman ?

Can't see the toughs but you can see the warm sector. It's the same on the GFS



And once you see a warm sector you have cold and warm fronts. Looks like the system is in early stages of developmment on Friday but the GFS has it beefy enough for more widesread snow then just showers.

Also how do you know the occluded front is draped back over Ireland ?

The chinks in the isobars - specifically over the north.

To me, albeit great charts, I wonder has the potential shifted East to UK leaving us drier after Friday

I think it's an upgrade on earlier ECM runs.

kstand

I live in London with the Mrs and little lad. Shes' due to fly from Heathrow to Dublin on Sunday at lunchtime for the Christmas. What chances do ye give of that being able to happen based on these models?

darkman2

168hrs incoming from the Northwest.....more significant snow.








OK I will stop now!:pac:

Tom Cruises Left Nut

darkman2 wrote: »

OK I will stop now!:pac:

Please don't !! :pac:

Will be interesting to see what the GFS run says, they seem to be coming to agreement now

Elmo5

Met Eireann have issued a warning

Weather Warning

Issued at 14 December 2010 - 18:41
Weather Advisory
Weather Advisory for severe cold weather and snow over the coming days.

Very cold wintry weather will develop across Ireland during Thursday, sweeping down from the north, and leaving a severe frost and ice on Thursday night. Through Friday and the weekend afternoon temperatures will be in the range zero to plus 3 C, with night time temperatures typically minus 3 to minus 8 C.
Snow is expected to return. Through Thursday, Friday and Saturday this will be mainly in coastal counties of the north and west (although isolated snow showers could occur anywhere), with a more widespread mix of rain and snow following for Sunday and Monday. Roads will become icy each night wherever they are wet.

Regular updates will follow.

Deep Easterly

Evelyn was very calm on the 6/1 forecast I thought, almost like she was restraining herself from letting out a big"Whaaaa Whooo"!

redsteveireland

Deep Easterly wrote: »

Evelyn was very calm on the 6/1 forecast I thought, almost like she was restraining herself from letting out a big"Whaaaa Whooo"!

Were you in hiding? Looks like we could have an interesting couple of days ahead on the west. Wouldn't have been right for you to miss it.

Deep Easterly

redsteveireland wrote: »

Were you in hiding? Looks like we could have an interesting couple of days ahead on the west. Wouldn't have been right for you to miss it.

I am not too confident that my part of the west will see much to be honest but giving the nature of the wind stream, other parts will do much better. I think the Mayo hills will absorb most of the energy from these snow showers before they reach here but who knows how it will all turn out in the end

maquiladora

Wow

What a chart...

-12 to -14 uppers over the country with -16 just touching the northern coast.

:cool:

hotwhiskey

What you should of said Maq was



CARLSBURG don't do winter charts but if the did the would look like this.:D

maquiladora wrote: »

Wow

What a chart...

-12 to -14 uppers over the country with -16 just touching the northern coast.

:cool:

Harps

I know it probably wont but assuming that -16 does end up over us, what sort of temperatures would we looking at?

thetonynator

Looking at maq's chart, - 20 uppers nearly in scotland and tunisia in africa entirely covered by sub zero uppers. . . The worlds going mad! -12 uppers in france. . . Wtf? armaggedon? :P :P :pac:

TheMilkyPirate

18z be rolling out in a few minutes, I'll keep an eye on my low next wednesday :P

Vizual Pics

Nice image of the Greenland Express en-route, stopping off at Iceland and then next stop Donegal, Leitrim, Sligo, Mayo, Galway and down to WolfIre in Clare, Limerick, Kerry and everything east of the above..:D

Rikand

thetonynator wrote: »

Looking at maq's chart, - 20 uppers nearly in scotland and tunisia in africa entirely covered by sub zero uppers. . . The worlds going mad! -12 uppers in france. . . Wtf? armaggedon? :P :P :pac:

more like The Day After Tomorrow

Vizual Pics

Harps wrote: »

I know it probably wont but assuming that -16 does end up over us, what sort of temperatures would we looking at?

Usually in Ireland you add 10 to the 850temps to get the surface so -14 uppers would give approx -4 at ground level.

JONJO THE MISER

Cant freakin wait from snow starved kerry.

WolfeIRE

Article by Fergal Tierney on Polar Low potential this weekend
http://www.irishweatheronline.com/2010/12/polar-low-potential-for-ireland-this.html