Ireland Regional Weather Discussion

[ronan]

Snowing the past 30 mins. Good to see a warning out

[mountain shadow]

1 minute ago, ronan said:

Snowing the past 30 mins. Good to see a warning out

Yes, that's a nice band there. Not making much progress East though, there's a shocker!

[ronan]

6 minutes ago, mountain shadow said:

Yes, that's a nice band there. Not making much progress East though, there's a shocker!

No chance of it lying where I am just now but the hills definitly getting a bit whiter. Looking forward to a bit of lamppost watching tonight. Hopefully they push further SE and everyone gets a bit of action 

[na52]

Lying on my grass and slush on the road but 10m less elevation at the bottom of street nothing..should improve later hopefully

[Sperrin]

That last band of showers has broken up significantly when it crossed Donegal...obviously not too keen on Tyrone

Next one moving in looks a bit more robust

[BIG LAD]

Temps up to 3c now so probably not cold enough for snow today.

[Sparky72]

At last a decent snow shower. Big fluffy flakes. Not settling but just to see it is good!

[Summer Snow]

4 hours ago, Summer Snow said:

Snowing away in South j Kilkenny 

Nice covering here in South Kilkenny... totally unforecast... very slight thaw now but should keep most of our  cover intact  today...lovely stuff....hopefully everyone gets in on the action this weekend.... 

[BIG LAD]

22 minutes ago, Summer Snow said:

Nice covering here in South Kilkenny... totally unforecast... very slight thaw now but should keep most of our  cover intact  today...lovely stuff....hopefully everyone gets in on the action this weekend.... 

Ninja snow is always the best!

[Summer Snow]

20 minutes ago, BIG LAD said:

Ninja snow is always the best!

Surely is Big Lad..... just goes to show ...get the cold air in place and surprises can happen....no model nor Met Eireann showed a band of heavy snow pushing accross Munster amd south Leinster this morning ...you guys up north should see some decent snow over weekend.....Colder upper air temps sinking South all the time now.....

[jello]

Snowed lightly for a minute here.   Literally lightest snow ever.  Grass has a few tiny bits of white.  Hoping for more.  

Edited January 22, 2021 by jello

[BIG LAD]

2 minutes ago, Donegal said:

Letterkenny

 

Alot of cars stuck? Looks quite high up.

[ronan]

That's Mountain Top road and is pretty high above a Letterkenny. Would be up the road above the hospital I think. 

[booferking]

Not a single flake here.

[Sperrin]

Can anybody explain the physics behind shower activity? Always fascinates me why some showers will push well inland and maintain their intensity, whilst other times (like today) they disintegrate 20-30 miles inland. Some really beefy showers completely fell apart this afternoon within 15 miles of travel.

[mountain shadow]

BBC weather looked absolutely crap snow wise there, even Sunday mornings offerings disappeared. 

Another disappointing Northerly.

[The Weather Watcher]

11 minutes ago, Sperrin said:

Can anybody explain the physics behind shower activity? Always fascinates me why some showers will push well inland and maintain their intensity, whilst other times (like today) they disintegrate 20-30 miles inland. Some really beefy showers completely fell apart this afternoon within 15 miles of travel.

There are multiple reasons why. Could be less moisture rich air inland, could be surface to troposphere temperature difference, slack air flow/divergence.

In this case the showers are developing due to sea to troposphere temperature difference (moist warmer air will try rising above the colder air aloft). This is larger than the land to troposphere temperature difference, and with less moisture over land, any air that rises is drier (meaning no shower development). With no development, the showers fade. 

There is also slack isobars, meaning wind divergence more probable. In summer/thunderstorm potential you will hear of convergence zones. Convergence helps aid convection (and organised storm development), but divergence is the opposite, and aids sinking air. 

[na52]

25 minutes ago, Sperrin said:

Can anybody explain the physics behind shower activity? Always fascinates me why some showers will push well inland and maintain their intensity, whilst other times (like today) they disintegrate 20-30 miles inland. Some really beefy showers completely fell apart this afternoon within 15 miles of travel.

It does feel like I get trolled by clouds sometimes ....hoping these improve the penetration situation later 

[Sperrin]

Many thanks @The Weather Watcher

[mountain shadow]

Angie's NI graphics looked crap too away from the NW. Nothing push South East.

No snow for Ulster on Sunday.

Crap.

[The Weather Watcher]

4 minutes ago, Sperrin said:

Many thanks @The Weather Watcher

No problem.

Apart from the cold air aloft, on this occasion all other forcings are not conducive to good shower activity, so we just have the wishbone kind of effect, with showers only really on windward coasts. What could aid us better is even colder uppers (more upward forcing), small patches of moist and milder air (for trough development) or converging winds.

 

[na52]

30 minutes ago, The Weather Watcher said:

No problem.

Apart from the cold air aloft, on this occasion all other forcings are not conducive to good shower activity, so we just have the wishbone kind of effect, with showers only really on windward coasts. What could aid us better is even colder uppers (more upward forcing), small patches of moist and milder air (for trough development) or converging winds.

 

Please feel free to ignore but can I also ask why I can see the smoke from nearby houses ( the surface air ) being blown in the exact opposite  direction of travel than the clouds, is the surface air cold enough to be drawn out to sea even against the prevalling wind ? 

Edited January 22, 2021 by na52

[The Weather Watcher]

16 minutes ago, na52 said:

Please feel free to ignore but can I also ask why I can see the smoke from nearby houses ( the surface air ) being blown in the exact opposite way direction of travel than the clouds, is the surface air cold enough to be drawn out to sea even against the prevalling wind ? 

Commonly known as a land breeze. Apart from possible surface winds changing direction due to buildings/land interference, it is most likely a land breeze. These do prefer to happen at night as the inland temperature gets colder, plus with the slack NW winds atm it'll not be hindered. The winds increase somewhat later tonight, enough to stop the land breeze from happening. 

I might add also that wind divergence can cause unusual surface wind directions, although it is more likely to cause sinking air, fog, etc.

Edited January 22, 2021 by The Weather Watcher

[na52]

1 minute ago, The Weather Watcher said:

Commonly known as a land breeze. Apart from possible surface winds changing direction due to buildings/land interference, it is most likely a land breeze. These do prefer to happen at night as the inland temperature gets colder, plus with the slack NW winds atm it'll not be hindered. The winds increase somewhat later tonight, enough to stop the land breeze from happening. 

Thanks

[na52]

10 minutes ago, The Weather Watcher said:

Commonly known as a land breeze. Apart from possible surface winds changing direction due to buildings/land interference, it is most likely a land breeze. These do prefer to happen at night as the inland temperature gets colder, plus with the slack NW winds atm it'll not be hindered. The winds increase somewhat later tonight, enough to stop the land breeze from happening. 

I might add also that wind divergence can cause unusual surface wind directions, although it is more likely to cause sinking air, fog, etc.

Funny you added that as I did see a fog forming earlier and thought that was a bit out of place as there was a light snow on at the time