Cold Spell Late Feb/ Early March Technical Discussion only MOD NOTE POST #1

Kermit.de.frog

cherryghost wrote: »

Icon wants to keep the cold going into next week, with a 12-15hrs dumping of heavy snow across Munster and much of Leinster, then cumulating with snow showers for the rest of the weekend. GFS slides the low further west, but precip hasnt changed and has most of the country pasted with white stuff, with sleet/rain following on through the weekend. Two very different low movements though.

Interesting commutes on Friday :pac:

Kermit.de.frog

jdcv94 wrote: »

I'm still a beginner at reading these charts but I love the weather, people have said before that it's bad for snow if this low moves west like it is on that chart. How come this will bring crippling snow in this case?

The flow is continental which is what we want - keep surface temps and dew points low. The fronts are thrown up over us ahead of the system.

Perfect mix.

cherryghost

GEM run this afternoon looks pretty bad. Wants thaw starting Friday morning.

UKMO still looks ok until Saturday

ThaitaniumM

ECM rollout should be interesting

gabeeg

cherryghost wrote: »

GEM run this afternoon looks pretty bad. Wants thaw starting Friday morning.

UKMO still looks ok until Saturday

It's not great, but it's also not far off showing a prolonged battleground scenario

dacogawa

The GFS is still showing "The Beast from the East" getting a "Clout from the South" on Friday.





I still don't trust the GFS above the ECM no matter how much I want to on this run, not sure any of them are handling things well just yet

cherryghost

gabeeg wrote: »

It's not great, but it's also not far off showing a prolonged battleground scenario

For sure, all models definitely showing overnight snow Thursday into Friday morning still, which is pretty amazing considering all the models have the low moving different directions, but the end result is still the same for us.

The only thing they dont agree on is what comes after precip hits landfall. Will it stall? Will it turn to rain as it passes up? Will it slide west/east and leave the cold digging in through the weekend? I certainly wouldnt bet on any of it right now.

snowstorm445

ThaitaniumM wrote: »

ECM rollout should be interesting

ECM runs have been fairly poor over the past day or so as regards the track of the low, here’s hoping it’ll switch over though.

Casualsingby

Met office issued a Northern Ireland wide snow warning for Friday. They currently expect it to travel north judging by that.

Kermit.de.frog

Hirlam picking up some real intensity in the showers on Wednesday

SleetAndSnow

Just catching up on the models after school, correct me if I am wrong (Please do I am learning so much so fast! ), but it looks more severe for both the south and east coasts on the latest models, meaning both Cork and Dublin even versus yesterday? The snow which could fall along with the winds look pretty severe. Given that Dublin already has lying snow, this looks strong. Models also seem to be showing less warming to the south aswell (which I am happy about!)

cherryghost

HIRLAM was very accurate with the wind storms this winter and considering the system was developed by Scandanavians, I believe its snow accuracy will be good too

EDIT: HIRLAM for the next 48 hours looks great. Only had a look at it there.

Gaoth Laidir

Snow grains continuing in Tallaght. Snow grains due to the very shallow convection, limited by the inversion. Cloud tops are only arpund 1500-1800 metres. When the inversion shifts away later we will see the convection deepen and get down to the business end of proceedings.

Vxlks

Kermit.de.frog wrote: »

Hirlam picking up some real intensity in the showers on Wednesday

Can you link that page? i want to know the intensity its showing for Dublin tuesday night into wednesday ty!

cherryghost

Vxlks wrote: »

Can you link that page? i want to know the intensity its showing for Dublin tuesday night into wednesday ty!

http://www.meteociel.fr/modeles/hirlam.php?map=430

MichealD

Kermit.de.frog wrote: »

Hirlam picking up some real intensity in the showers on Wednesday

Looks like a lot of activity over the South East on this one again. Curious why Met Eireann have left Wexford off their current Orange alert although its obviously an evolving situation. Seems to be directly in the line of fire on a lot of models.

https://www.met.ie/nationalwarnings/default.asp

SleetAndSnow

Cork Aiport reporting light snow showers in their TAF forecast (30% possibility 8am tomorrow) :

http://en.allmetsat.com/metar-taf/ireland.php?icao=EICK (find this page great for translating taf)

TAF: EICK 261100Z 2612/2712 11018KT 9999 FEW020 TEMPO 2612/2617 11019G29KT BECMG 2617/2620 08010KT PROB30 TEMPO 2700/2708 5000 -SHSN SCT018CB BECMG 2704/2706 05012KT

JCX BXC

SleetAndSnow wrote: »

Cork Aiport reporting light snow showers in their TAF forecast :

http://en.allmetsat.com/metar-taf/ireland.php?icao=EICK (find this page great for translating taf)

TAF: EICK 261100Z 2612/2712 11018KT 9999 FEW020 TEMPO 2612/2617 11019G29KT BECMG 2617/2620 08010KT PROB30 TEMPO 2700/2708 5000 -SHSN SCT018CB BECMG 2704/2706 05012KT

They're forecasting a 30% possibility from midnight to 8am tomorrow of that occuring.

JCX BXC

I note the GFS is giving very little back edge snow on the front despite another shift westwards.

Probably better off, as it would likely freeze on impact and cause havok.

lucernarian

cherryghost wrote: »

http://www.meteociel.fr/modeles/hirlam.php?map=430

Thanks! Just what the doctor ordered (along with a prolonged stay in bed and out of sight order for ICON...)

M.T. Cranium

GFS scenario looks a bit counter-intuitive, if the low were to miss that far south, cold air would probably not retreat that far north. GEM looks a bit more realistic with a similar evolution, looking at it I thought of "three strikes and you're out" for the Atlantic.

PukkaStukka

The Dublin airport TAF says there are CB's about. I thought there wasn't enough oomph for that scale of convection?

http://en.allmetsat.com/metar-taf/ireland.php?icao=EIDW

cherryghost

cherryghost wrote: »

http://www.meteociel.fr/modeles/hirlam.php?map=430

Tomorrow wouldn't be great for the Dundalk/North Louth area in terms of streamers (NE wind direction no good for here). Wednesday looks better though towards the end of that Hirlam run if the wind shifts ESE.

downwiththatsor

Euro4 just out for 9am Wed.

dacogawa

ECM looking good for Wednesday 12pm, looks like this mornings Thursday 12am chart, bigger cold pool behind too

downwiththatsor

The eagle probably had seen this, warmer uppers but heavy snow initially I assume.

dacogawa

The "Clout from the South" looks on course 96 hours out on this run

ninebeanrows

downwiththatsor wrote: »

The eagle probably had seen this, warmer uppers but heavy snow initially I assume.

I can guarantee the eagle didn't see this chart and also it's a decent chart- an improvement from this AM I believe ?

Kermit.de.frog

Weathercheck wrote: »

I can guarantee the eagle didn't see this chart and also it's a decent chart- an improvement from this AM I believe ?

A lot of snow alright

https://weather.us/model-charts/euro/ireland/significant-weather/20180302-0000z.html

Weathercheck

Weathercheck wrote: »

I can guarantee the eagle didn't see this chart and also it's a decent chart- an improvement from this AM I believe ?

Close up of that +96 hrs chart. Looks decent for the midlands, east and north for me.