scotland Scotland Regional Discussion 17th March 2013 18:30>

[Sunny Leith]

The snow had stopped and there were patches of blue sky so I popped out for lunch...

I have to say that is never late-March out there. Never !

[Bullseye]

BBC1 weather look good for Scotland more so central belt south the places that missed the snow in past 72 hours, Saturday was better with "snow pushing north on Saturday"

[Richard Taylor]

More snow into Aberdeen city today than yesterday I would say, but not causing too many problems, least not in the city centre.

[LomondSnowstorm]

Does the one mainly covering the east coast of Scotland actually warrant a warning?

To me that's basically saying, don't expect to see much snow, and it ain't likely to lie enough to cause any real problems.

It's always a tough call with showers, usually often the models underestimate their intensity though in this instance it doesn't look like it's likely to be all that problematic. Skew-ts are suggestive of not a huge amount of capping up to tomorrow afternoon/evening but not really suggestive of major convective activity for southeast Scotland, for Aberdeenshire however it does look quite a bit more interesting overnight and some fairly heavy showers could pep up :

The best profile for snow in the next 3 days is Friday night for Renfrewshire, which is pretty textbook for a big frontal snowfall:

[Buriedundersnow]

right i thought we would have a better idea what was happening today but we are still sat on the fence a bit

GEM

GFS

ECM

UKMO

NAE has it this far at 48h

NASA again has it same position as NAE and wants to bring the front in

hopefully we will find out more by tonight and find out one way or another what this front is going to do

[LomondSnowstorm]

What a fountain of knowledge! Very good post.

Could you please elaborate a little on the end of point 4 (-8 rule) if you have time.

Thanks

Sure, the gist of it is that you need -8C 850hpa temperatures in an easterly flow for lying snow to occur in lowland eastern Scotland. It's not based on anything other than past experience of these events but so far the rule has held up pretty well. For anything other than easterlies or southeasterlies -5C upper air temperatures are usually fine and higher than that can still sustain snow under some circumstances (up to 0C even in a southerly flow with cold embedded at the surface) but without -8C or lower uppers the coastal marginality tends to lead to slushy coverings at best.

[Buriedundersnow]

wow its quiet in here especially with us still looking at a front possible making it to us

[Buriedundersnow]

lets look at how the NAE has progressed the front on its 48h chart on every run from its last few runs

todays 12z rolling out now so we will see where it progresses to on that run soon

[FrenchScotPilot1]

Sure, the gist of it is that you need -8C 850hpa temperatures in an easterly flow for lying snow to occur in lowland eastern Scotland. It's not based on anything other than past experience of these events but so far the rule has held up pretty well. For anything other than easterlies or southeasterlies -5C upper air temperatures are usually fine and higher than that can still sustain snow under some circumstances (up to 0C even in a southerly flow with cold embedded at the surface) but without -8C or lower uppers the coastal marginality tends to lead to slushy coverings at best.

Great thanks! I knew abut the -5 or lower but it indeed depends on specific location.

[Ravelin]

wow its quiet in here especially with us still looking at a front possible making it to us

Well personally I don't think the front will make it to me in any meaningful way so no excitement here, and anyway, as I said earlier, I'm all snowed out. Assuming the front doesn't make it, then I'm still stuck under the cold pool and I'm all colded out too.

I'll be happy for others though if they get snow that they haven't had so far this winter.

I'd consider taking advantage and heading to Lecht/Glenshee at the weekend but I suspect the forecast winds will make that either impossible or unpleasant.

[Buriedundersnow]

this front caper is a real pain in the bum.

will it come will it not.

in both ways it is good for us.

if it comes in we get a big dump of snow but it will raise uppers and give us a fight to bring them back down

if it misses we stay in the really cold air longer and really establish a solid cold pool over us so its a bit win win either way.

would also add if it does miss us and we build a cold pool sooner or later we will see a breakdown and still probably a frontal event so if it does miss dont look at it as game over look at it as prolonging our cold spell and we will still have the breakdown to look forward to.

so not all doom and gloom folks its actually win with big dump or win win if it misses

Edited March 20, 2013 by Buriedundersnow

[Buriedundersnow]

12z NAE looks promising it has the front further at 42h than it did at 48h on the previous run just look at the last chart on my previous NAE post

[Buriedundersnow]

NAE 12z 48h chart looks really good

[Buriedundersnow]

on this pic of the NAE 48h chart i have put a black line now if u look at the isobar lines u see kinks right through the chart now these kinks pushing out from the low is our friend and what we need to keep seeing on these charts as this is helping force the front into us against the block

[Buriedundersnow]

heres the NAE 2m temp chart from the end of the 12z run so assuming this is right and the front does make it in with 2m temps that low it shouldnt have any problem settling

[FrenchScotPilot1]

heres the NAE 2m temp chart from the end of the 12z run so assuming this is right and the front does make it in with 2m temps that low it shouldnt have any problem settling

What are the DP forecasted at?

[Snowplough33]

NAE 12z 48h chart looks really good

Could you please post the uppers as I can't access them at work.

[Buriedundersnow]

What are the DP forecasted at?

heres dewpoints, uppers and thickness.

i am not sure what parameters we need in frontal snow for it to stay snow maybe LS can help me here

[FrenchScotPilot1]

heres dewpoints, uppers and thickness.

i am not sure what parameters we need in frontal snow for it to stay snow maybe LS can help me here

Fair question, I bow to LS's expertise here and await with great anticipation

[Buriedundersnow]

Well personally I don't think the front will make it to me in any meaningful way so no excitement here, and anyway, as I said earlier, I'm all snowed out. Assuming the front doesn't make it, then I'm still stuck under the cold pool and I'm all colded out too.

I'll be happy for others though if they get snow that they haven't had so far this winter.

I'd consider taking advantage and heading to Lecht/Glenshee at the weekend but I suspect the forecast winds will make that either impossible or unpleasant.

yeah it might be a push to get it up there the next run or two on the NAE will be crucial for u to give u an idea of how far northeast the front will get

[101_North]

NAE 12z 48h chart looks really good

That's a big shift north if it verifies!

[Guest]

heres the NAE 2m temp chart from the end of the 12z run so assuming this is right and the front does make it in with 2m temps that low it shouldnt have any problem settling

It's only going to settle on any vertical surfaces BUS:

[DR(S)NO]

matthew Hugo on Twitter:

Quote

Matthew Hugo â€@MattHugo81 11m

We are quite reserved in the UK but given data I continue to see, if this was the US or Canada Fri's low is an equivalent major winter storm

Hmm,interesting quote from Matt Hugo just posted over on the MT.Interesting Weekend ahead weather wise.

[FrenchScotPilot1]

It's only going to settle on any vertical surfaces BUS:

Especially the east coast based on this. Great time to go to the beach Friday lunchtime then

Edited March 20, 2013 by FrenchScotPilot1

[November13]

I can't wait to see the BBC forecast when i get home. I think we should have a good idea by this evening if the Day After Tomorrow is going to happen!

Our footballers might not stop Bale but the weather might.