Snow on paddys day?!

darkman2

Hi everyone. There is now support for a snow event across the Southern half of the country during Thursday. Sleet probable on coasts. However inland accumlations may be on the cards:D






This is only 48hrs away. The precip would be of snow upon hitting the east coast 6 Thursday morning. Watch this space:)

Crazy that its 48hrs away

BTW Darkman,I usually knock 1 to 2 degrees off those GFS temps especially in an Easterly.

Dewpoints are the key

ninebeanrows

Can only see snow to the north and east of that precip.

Dew points are only below freezing for the east coast and north.

But yes very interesting places like Leinster and south Ulster may get a few flakes:)

ninebeanrows

Lets hope it shows up on more runs because i "think" it would fall as snow..

All variables just about in place;)

GFS dewpoints are ok and minus near the East coast but further south, it could be an entirely hill event.

http://www.wetterzentrale.de/pics/Rtavn4810.png

Inland a few miles (4 or 5 only) and a bit of height and probably all snow.
I wouldnt rule out snow on the coast either but I'd expect it to be wet and only slushing the grass rather than crunching under the feet.
In that type of coastal snow,it could snow moderately for a couple of hours and look good falling but only deliver a slushy covering away from hills.
A slushy covering that would go quickly when the sun got out.

darkman2

Earthman wrote:

Crazy that its 48hrs away

BTW Darkman,I usually knock 1 to 2 degrees off those GFS temps especially in an Easterly.

Dewpoints are the key

The 2C in the midlands all day suggests accumulation. Thats a massive drop in temps from the 6z. A trend perhaps;)

darkman2

darkman2 wrote:

The 2C in the midlands all day suggests accumulation. Thats a massive drop in temps from the 6z. A trend perhaps;)

If we are to start beieving the GFS trends, then we'll say goodnight to the snow in the East after monday as it goes to say how you doin' to sligo and Donegal...

Any comment on the rise in 850 temps on saturday and sunday and the related 2m temps and the effect on snow cover?

darkman2

Earthman wrote:

If we are to start beieving the GFS trends, then we'll say goodnight to the snow in the East after monday as it goes to say how you doin' to sligo and Donegal...

Thats a good point, im still thinking the GFS hasnt got that nailed yet. Its only one run so obviously we need others to agree. Nice to see thoguh at such short notice:)

Villain

Darkman2 if that comes off what kind of ammounts would we see?

ninebeanrows

we could be talking 4-6cm's of snow with that:)

darkman2

irish1 wrote:

Darkman2 if that comes off what kind of ammounts would we see?

Not much really 2 - 5cm maybe. But more on hills. It will in all probability fall as sleet along the East coast (assuming it happens of course). It may not happen though. Precip could be an outlier for Dublin in the Ensembles. Hopefully not though:)

darkman2

darkman2 wrote:

Thats a good point, im still thinking the GFS hasnt got that nailed yet. Its only one run so obviously we need others to agree. Nice to see thoguh at such short notice:)

I think I'd kind of thrust the GFS at 48 hrs notice.
From reading the US NWS discussions, they use a mix of all to reach a forecast there using phrases like,I think one NWP has over cooked the temps on that so I'll go for this scenario and this other NWP has been more consistant etc.

However, they are not afraid to completely chane their forecasts within 24hrs as I found out the last time I was there.

Point being this wouldnt be a nowcast scenario in january or early february,it would be a dead cert with slight variations.

Currently its a now cast.

ninebeanrows

Although in and around Dublin i'd only expect it to ly on car, grass etc
and only limited amounts on tarmac;)

darkman2

Earthman wrote:

I think I'd kind of thrust the GFS at 48 hrs notice.
From reading the US NWS discussions, they use a mix of all to reach a forecast there using phrases like,I think one NWP has over cooked the temps on that so I'll go for this scenario and this other NWP has been more consistant etc.

However, they are not afraid to completely chane their forecasts within 24hrs as I found out the last time I was there.

Point being this wouldnt be a nowcast scenario in january or early february,it would be a dead cert with slight variations.

Currently its a now cast.

Im confused, whats your view on this:



6 hrs of snow maybe.

darkman2

darkman2 wrote:

Not much really 2 - 5cm maybe. But more on hills. It will in all probability fall as sleet along the East coast (assuming it happens of course). It may not happen though. Precip could be an outlier for Dublin in the Ensembles. Hopefully not though:)

Using local knowledge to some degree In Tullow or Hacketstown in theory ,Irish1 is probably 20 to 30 miles inland and to the west of the southern edge of the wicklow mts and also has a bit of high ground around him too so It should be an all snow event there with a possible 2 or 3 inches.Maybe more,maybe less but settling yes it should do.

That said as its a now cast it all depends on where the precip develops(if it develops and Glasnevin thinks it will) and goes

darkman2

darkman2 wrote:

Im confused, whats your view on this:



6 hrs of snow maybe.

I'd have thought that only for the fact that one of those charts was posted for the friday 2 weeks ago event and what did we all get a light temporary covering for some and nothing for most.

Fascinating though if I'm reading it correctly(I'm not too familiar with those) but it shows snow on the coast turning to rain as it heads south westwards.
Ironic that scenario as it progs snow for the coast and rain for inland.

Looks to me to be a very technical interpretation of GFS 850 temps.
Local knowledge goes into forecasts though.

lucernarian

Earthman wrote:

nland a few miles (4 or 5 only) and a bit of height and probably all snow.
I wouldnt rule out snow on the coast either but I'd expect it to be wet and only slushing the grass rather than crunching under the feet.
In that type of coastal snow,it could snow moderately for a couple of hours and look good falling but only deliver a slushy covering away from hills.
A slushy covering that would go quickly when the sun got out.

Living in south Louth, 5 miles from the coast and on a reasonable elevation, this is music to my ears:p

I didn't think that there was any chance of organised precipitation but after my reading of GFS for Thursday morning, it seems that our possible feature is based on a proper front as opposed to a small trough.

I still don't expect to see more than a dusting from that here though, as the precipitation is too far south. Also, the ground may be or may become too wet for snow to settle unless it were heavier.

darkman2

Earthman wrote:

I'd have thought that only for the fact that one of those charts was posted for the friday 2 weeks ago event and what did we all get a light temporary covering for some and nothing for most.

Yes however we are on the windward coast this time. -8 - -10 isotherm coincides with its arrival (convienient) and dewpoints probrably below zero. It is still marginal thoguh. These unforseen things always are. We should see a flake or two I think;)

darkman2

Guess what, ensembles are in and................there should be more precip in Dublin:D In fact the control is at the lower end of precip for Thursday;)



12 Thursday looks good when you consider there could/should be more precip.

Looked at the DP's on NW there darkman and they seem to be above zero on this run.
Thats not just borderline,it's thin ice literally (or no ice at all)

I'd expect that to be out a bit though,they probably should be below zero.
You would need a -2 there tbh or at least a between -1 and -2c

That said,they have the snow risk ramped up to 90 or 95% (did Steve draw them up )

Villain

Earthman wrote:

Using local knowledge to some degree In Tullow or Hacketstown in theory ,Irish1 is probably 20 to 30 miles inland and to the west of the southern edge of the wicklow mts and also has a bit of high ground around him too so It should be an all snow event there with a possible 2 or 3 inches.Maybe more,maybe less but settling yes it should do.

That said as its a now cast it all depends on where the precip develops(if it develops and Glasnevin thinks it will) and goes

Cheers for that Earthman, I hope it comes off and I can get some nice snow photos, might have to visit the relatives in Knockananna

darkman2

darkman2 wrote:

Guess what, ensembles are in and................there should be more precip in Dublin:D In fact the control is at the lower end of precip for Thursday;)

Well unfortunately according to that though the precip should be rain on saturday and sunday...
Now thats where we say :rolleyes: to the GFS given what the ECM says.

I'm gone now for a while but do post up the ECM later.

darkman2

Earthman wrote:

Well unfortunately according to that though the precip should be rain on saturday and sunday...
Now thats where we say :rolleyes: to the GFS given what the ECM says.

I'm gone now for a while but do post up the ECM later.

Eh there is no precip Saturday and Sunday;) Sure if they are good I will;)

ninebeanrows

The ensemblesa are in and show precip:D

A nice liggle amount too:D

darkman2

darkman2 wrote:

Eh there is no precip Saturday and Sunday;) Sure if they are good I will;)

Lol How do you know theres going to be none?

I know this might get up your goat sometimes(but it shouldnt) but what you have said is a perfect example of quoting a model when it shows something we like and dissing it when it doesnt.

Why shouldnt there be some precip with an Easterly on those days-you think it will be totally dry?
I dont think so.
I'll bow to the superior information of a now cast.

No precip at all on sat or sunday-ha ha

But anyway my central point was anything lying will have a couple of dryer days to thaw or disappear if its very little in the first place.

Lets be realistic and not carried away.

Definitely gone now-back later

ninebeanrows

2 day cold easterly then transient 2 days then 4 day cold northeaterly:D

Threat of snow starts Thursday 00z




Never expected to be ramping or thinking of snow on March 14th:D
But my mom always reminds me it snowed when my sisters were born
on March 30th:D

darkman2

Earthman wrote:

Lol How do you know theres going to be none?

I know this might get up your goat sometimes(but it shouldnt) but what you have said is a perfect example of quoting a model when it shows something we like and dissing it when it doesnt.

Why shouldnt there be some precip with an Easterly on those days-you think it will be totally dry?
I dont think so.
I'll bow to the superior information of a now cast.

No precip at all on sat or sunday-ha ha

But anyway my central point was anything lying will have a couple of dryer days to thaw or disappear if its very little in the first place.

Lets be realistic and not carried away.

Definitely gone now-back later

I mean meaningful precip. It would show up on the precip scale on the ensembles. Otherwise it is not worth talking about. Luckily for Thursday it looks great. Only one run though, hopefully its still there in the morning.

P.S Incidentally id like precip on Saturday and Sunday;)

ninebeanrows

hehehe i liked those charts ALOT:D

on the Met forecast:D

snow for the east, Midlands and south on Thursday:D

Villain

Jees WC for once I thought you were keeping a level head and it was all going soooo well. Now that your ramping we'r doomed!!!