Scotland/Alba weather discussion - Jan 2021 onwards

[Bullseye]

STV weather just now didn't even bother to look at any later than Saturday morning

[Sceptical]

7 minutes ago, Swave Snow said:

Great them Aviemore will too lol

Sean Batty was banging on about Beast from the East. Royal Deeside seeing the heaviest falls,  2 meter drifts on the higher routes. Sounded pretty apocalyptic

[LomondSnowstorm]

ECMWF looks pretty good at least up to Wednesday (probably a bit far out then to be too worried about the exact placement of that low, but it does seem that that's where the next potential breakdown or at least easing of the flow comes in), this for Tuesday to Wednesday:

I'm having trouble with my usual ECMWF precip data but the site itself shows at least some precipitation right down the east coast from Sunday morning right through, and on most of them it gets at least some way inland:

On a global model that's really as much as you can ask for - it's not going to really show much beyond that well but convective snow developing and moving inland somewhat for 3 days straight is a good sign certainly.

[Hairy Celt]

8 minutes ago, Sceptical said:

Sean Batty was banging on about Beast from the East. Royal Deeside seeing the heaviest falls,  2 meter drifts on the higher routes. Sounded pretty apocalyptic

Living up to his name as usual then.

[Ravelin]

12 minutes ago, Sceptical said:

Sean Batty was banging on about Beast from the East. Royal Deeside seeing the heaviest falls,  2 meter drifts on the higher routes. Sounded pretty apocalyptic

The worse thing was, he made it sound like a bad thing. 

Temp sitting around 0C here, still snowing but difficult to see how much due to a general lack of streetlights.

Edit: This would be interesting if it happened....

Edited February 4, 2021 by Ravelin

[Hairy Celt]

27 minutes ago, Blitzen said:

Em bealachs?... Nope, I'm NOT going to ask!!

Bealach... old Norse word for any part of the anatomy that needs regular scratching.

(You ever listened to that Radio 4 programme called 'the unbelievable truth'? It varies from uproariously funny to pretty tedious and back a few times in 30 mins...

[Hairy Celt]

Slizzardy out now. Not nice.

[Sceptical]

11 minutes ago, Ravelin said:

The worse thing was, he made it sound like a bad thing. 

Temp sitting around 0C here, still snowing but difficult to see how much due to a general lack of streetlights.

Snows finally resumed up here, slight covering on the car. Haven't checked the temperature as there's no street lighting up here either - no wonder i grudge paying the council tax.

According to the met office, constant heavy snow for Alford over the next 3 days.

Game on! 

Edited February 4, 2021 by Sceptical
Usual atrocious spelling.

[asjmcguire]

17 minutes ago, Sceptical said:

Sean Batty was banging on about Beast from the East. Royal Deeside seeing the heaviest falls,  2 meter drifts on the higher routes. Sounded pretty apocalyptic

I would say Imagine the Daily Express headlines! But then I thought - oh wait, they don't need actual facts to backup the (weather) headlines they write.....

[LomondSnowstorm]

The ECMWF even delivers the rarest of things - easterly snow for both Ayrshire and the Black Isle, in the one timeframe!:

 

It does try to break it down but even at this range struggles to erode the cold pool and instead delivers a pretty nice frontal snowfall (for those of us who aren't permanently scarred by this week):

Southerly and fairly slack winds with embedded cold does normally give you a better chance but that is really just for fun at this stage and to illustrate how difficult it could be to dislodge the cold once it's established.

[Hairy Celt]

5 minutes ago, LomondSnowstorm said:

The ECMWF even delivers the rarest of things - easterly snow for both Ayrshire and the Black Isle, in the one timeframe!:

 

It does try to break it down but even at this range struggles to erode the cold pool and instead delivers a pretty nice frontal snowfall (for those of us who aren't permanently scarred by this week):

Southerly and fairly slack winds with embedded cold does normally give you a better chance but that is really just for fun at this stage and to illustrate how difficult it could be to dislodge the cold once it's established.

So where's the black isle on that top chart? Cos the one I know doesn't have any snow over it!

Edited February 4, 2021 by Hairy Celt

[Mair Snaw]

Raining still... met office has me in a weather warning for snaw until Wednesday but the forecast is rain and a bit of sleet...

[doctormog]

Just now, Mair Snaw said:

Raining still... met office has me in a weather warning for snaw until Wednesday but the forecast is rain and a bit of sleet...

It should get better by the weekend for us.

[mardatha]

1 hour ago, Glaswegianblizzard said:

I don’t think it’s stopped raining in Glasgow all day. Not even briefly.

Same here near Jedburgh. Utter Pits.

[Hairy Celt]

2 minutes ago, doctormog said:

It should get better by the weekend for us.

[asjmcguire]

Whilst the temperature is apparently dropping in other parts of Scotland....

The Borders continues to climb. 4C now....

Will be able to wear shorts before long (if you don't mind your legs being soaking wet)

[LomondSnowstorm]

5 minutes ago, Hairy Celt said:

So where's the black isle on that top chart? Cos the one I know doesn't have any snow over it!

Fair point - it gets close but it doesn't quite reach the Black Isle until early Tuesday:

Edited February 4, 2021 by LomondSnowstorm

[GoldenJackel]

Indeed it is heavy precipitation but a little less white...

2.1C / 1.4C DP. I’m guessing it must be because the DP is too high.

Edited February 4, 2021 by GoldenJackel

[Kayemill]

4.2 deg here. Looking out the Bermuda shorts soon. My normal shorts policy is May till Oct but may have to re-assess. 

Edited February 4, 2021 by Kayemill

[Mair Snaw]

20 minutes ago, doctormog said:

It should get better by the weekend for us.

Sleet oh i cant wait for that..

[Wee County Exile]

7 minutes ago, GoldenJackel said:

Indeed it is heavy precipitation but a little less white...

2.1C / 1.4C DP. I’m guessing it must be because the DP is too high.

Same here along the road in Culter. Hopefully things will improve as the weekend progresses

[Mr Frost]

BEGONE marginal sh**e!!! 

This is all more like it. 

Sunday 15:00

 

Monday 15:00

 

Tuesday 12:00

 

Let’s see what becomes of it all! 

[shuggee]

36 minutes ago, asjmcguire said:

I would say Imagine the Daily Express headlines! But then I thought - oh wait, they don't need actual facts to backup the (weather) headlines they write.....

Has the Daily Express headlined the BFTE - actually getting it right for the first time amongst three years of garbage? I bet @Jo Farrowhas been keeping score?

[doctormog]

6 minutes ago, Mair Snaw said:

Sleet oh i cant wait for that..

Well you’re going to have to, so be patient. 

[Scottish-Irish Skier]

20 hours ago, Hairy Celt said:

Ablation? Where's SS when you need him? @Scottish-Irish Skier that is.

Sublimation is truly sublime.

That is evaporative cooling. 

Air so dry that it actually causes snaw to evaporate. Air in contact with ice should have a certain concentration of water vapour in it. If it is below that, the ice will directly evaporate to vapour. Just like e.g. CO2 dry ice on top of the pops.

As it does so, there is a latent heat of sublimation / vaporisation (solid ice to vapour transition) which cools the snowpack to the ice-vapour equilibrium temperature at the pressure concerned until it's all gone.

In the continental rockies, this is common, and snow doesn't melt, but simply evaporates. Also gives rise to 'champagne powder' which is superdry powder snow which lasts as it crystals don't surface melt (they evaporate) so there is no freeze-thaw cycle which tends to cement so hardening the snawpack. 

The sun helps the evaporation process by providing heat and you can see steam rising off the snaw....

Not something you really get in pishing wet Scotland. Does happen in the alps under dry higher pressure conditions.