Thunderstorms and Convective Potential (Dublin Floods 9/8/08)

Snowbie

An MCS (mesoscale convective system) is occuring over there yet again. Have been watching the Brighton cams on Meridian and saw lots of IC. There well use to them over there now in the SE. The last one in Ireland was August 2000 (Bay of Biscay storms)

Kippure

There was some good action through the midlands from about 5pm this evening, then it died down, More coming up from the south irish sea at the moment

TheGreenGiant

deadly! some nice intra and cloud to cloud lightning there.thanks for the upload:D

TheGreenGiant

Man i remember that storm Snowbie!! best storm i have witnessed in my lifetime so far.it hit here late afternoon and didn't end until the early part of the morning.the lightning show was spectacular!

Damomanye

darkman2 wrote: »

An emergency flood warning has been issued for Newcastle West apparently. The river is swelling fast (again).

Yea, all roads are closed now into the town acording to AA and NewsTalk

Mr Benevolent

B*stards! Getting all that lightning in one place. I'm off to Oz next year, hopefully should get a few good storms there.

darkman2

Snowbie wrote: »

An MCS (mesoscale convective system) is occuring over there yet again. Have been watching the Brighton cams on Meridian and saw lots of IC. There well use to them over there now in the SE. The last one in Ireland was August 2000 (Bay of Biscay storms)

I thought that was 1998 or 7 Maybe I was out of the country or something but the last storms like those in England here I saw were indeed from Biscay but it was before 2000. Seen nothing like it since. Also IIRC those storms brought ver little rain funny enough and whilst the flashes were brilliant fast and bright there was not much thunder. Started around 10 or 11pm here.

Snowbie

Deep Easterly wrote:

Although I am sure I read somewhere there was an exceptional total from a thunderstorm at Phoenix Park sometime in the past. Do you have any information about this off hand Mothman? I'd nearly swear in was in the 70mm range.

Is this what you recall Paddy?

Dub Meteorologist wrote:

5.3.2: The Mount Merrion Thunderstorm of 11 June 1963 (a 'home-brew' thunderstorm in a south-easterly continental air mass): Reading an old copy of the Irish Times for 11 June 1963 is quite interesting. The main headline refers to the forthcoming visit of President J.F. Kennedy to Ireland, and the possibility that phone lines may be jammed during his visit (due to the FBI taking over the GPO, I presume). This is also some comment on the recent 'Profumo' affair in London. In a small corner on the front page is the day's weather forecast, reading "Another warm and sunny day, but isolated thunderstorms will break out in Munster later" or words to that effect. Not too bad a forecast for 1963....

Of course, later that day many Dubliners experienced their worst storm in living memory, when a violent thunderstorm over the Mount Merrion district deposited 184mm (7.5 inches) of rain in just a few hours, with 3.5 inches of this falling in one hour. It is quite possible that well over 200mm fell in an area where there were no rain gauges, indeed estimates of up to 235mm (9 inches) have been quoted. There was also violent thunder and lightning

TheGreenGiant

why o why have we not had any mcs' in ireland since 2000:(

Danno

1997 it was indeed.

TheGreenGiant

it was definitely 2000 because i remember my cousin passed away the day after it.my dad couldn't even make it home from dublin that night the storm was so bad!

darkman2

Snowbie wrote: »

Is this what you recall Paddy?

Charts from 11th June 1963

Snowbie

darkman2 wrote: »

I thought that was 1998 or 7 Maybe I was out of the country or something but the last storms like those in England here I saw were indeed from Biscay but it was before 2000. Seen nothing like it since. Also IIRC those storms brought ver little rain funny enough and whilst the flashes were brilliant fast and bright there was not much thunder. Started around 10 or 11pm here.

In 2000 it began at noon and lasted untill 2am in the eastern seaboard.
Yep high based which depicts MCS which can be dry and electrical( rain falling into lower dry air evaporates is called Virga) but this was not entirely dry.
Some cloudbursts led to flooding.

darkman2

Lads that storm over South East England. Watch what will happen it as soon as it hits the North Sea. Its gonna explode. MSC's tend to do that when they hit water.

darkman2

Snowbie wrote: »

In 2000 it began at noon and lasted untill 2am in the eastern seasboard.
Yep high based which depicts MCS which can be dry and electrical( rain falling into lower dry air evaporates is called Virga) but this was not entirely dry.
Some cloudbursts led to flooding.

Must have missed that. We got some bursts of heavy rain but not persistant in the storm I was referring to and it was dry more often then not. Having said that im not complaining - that was the most spectacular storm ive ever seen in Ireland. You must remember it surely? It was in August 98 or 7. Your not all that far from me.

Snowbie

Usually the London area is the max of my detector but inaccurate due to the distance but as the lightning is high based its getting not all but some lightning. This must be IC from the anvil.

Weather BOFH

Here' a time lapse I recorded today, most of the action was well west of here, but you can see the convection building out towards Kildare/Meath earlier this evening.

TheGreenGiant

i do remember a good storm in 1998 but the 2000 one will never leave my memory lol

TheGreenGiant

thats a really cool time lapse:D loved the convection near the end of the video

Snowbie

darkman2 wrote: »

Must have missed that. We got some bursts of heavy rain but not persistant in the storm I was referring to and it was dry more often then not. Having said that im not complaining - that was the most spectacular storm ive ever seen in Ireland. You must remember it surely? It was in August 98 or 7. Your not all that far from me.

I have a journal DM on these noted down before my PC days, will look up to be exact. Though 1998 i spent most of the Summer in Holland,(seen a few there).
Just refering to the last MCS which was 2000 which was memorable in recent times. 1990(world cup year) we had one too but was not a long lasting affair, kinda ran out of steam iirc.

Snowbie

nemonoid wrote: »

Here' a time lapse I recorded today, most of the action was well west of here, but you can see the convection building out towards Kildare/Meath earlier this evening.

You also captured a rotating updraft at time 1:45-1:55 in the clip. Excellent again.

TheGreenGiant

darkman2 wrote: »

Lads that storm over South East England. Watch what will happen it as soon as it hits the North Sea. Its gonna explode. MSC's tend to do that when they hit water.

you were definitely right about the storms intensifying as they reached water. peak rate is 31 strikes/min!!

Danno

Is there thunder over shannon?

Snowbie

TheGreenGiant wrote: »

you were definitely right about the storms intensifying as they reached water. peak rate is 31 strikes/min!!

MCS don't usually interact with water. It's all to do with mid to upper levels. In the mid levels you have the ingredients, the moisture, the warm plume and the ML Cape to name a few, it's why there elevated. Surface both land or water don't develop these systems kill or build these.

Nocturnal cooling of the cloud tops keeps the temp well below -50C and with deep level shear which keeps the longevity of MCS ongoing.

The WASP(wide area storm probe) which is a triangulation of detectors and not single point detection is coming out at a peak rate of 16 p/min with 389 strikes in the last hour.

TheGreenGiant

thanks Snowbie, good info there i was getting the info from www.isleofwightweather.co.uk

Sierra Oscar

Err . . . Met Éireann duty manager had this to say about todays weather:

"But once you go away from the Dublin area, in the west and north it's just traces [of rainfall]. Kilkenny's the closest with 8mm and Mullingar 5mm. The worst of it was certainly along that part of the east coast,"

It is funny, considering a record for most rain to fall in an hour was broken in Shannon.

Source: Irish Times

TheGreenGiant

indeed lol maybe he didn't hear about it haha

Snowbie

TheGreenGiant wrote: »

thanks Snowbie, good info there i was getting the info from www.isleofwightweather.co.uk

I know this site and the trouble he has had with it with a reflection problem but he is infairness capturing all sferics his detector catches.

For instance an IC strikes you may get a return signal from several points of the lightnig branch IC, this tends to happen even with mine. Not unusual it is just a very sensitive piece of equipment.
Also will push the strikes rates up at his point of detection and no wrong with that. If a 2nd detector has also captured the same branch it will do the same and plot in on the triangulated map as the total from that sferic.

This is why the strike rates are lower on triangulated even though i have counted 23 detectors including mine all capturing strikes and they are correctly plotted direction to map and where software will then determine the accuracy for strikes will be as accurate for that strike from the triangulation point of view.

Snowbie

darkman2 wrote: »

Yep thats some serious action over there


vid http://s18.photobucket.com/albums/b145/jshaw46/?action=view&current=6thAugustElevatedCells.flv just uploaded.

Thanks for sharing, ill bet a few more be available tomorrow,

TheGreenGiant

ah right yeah, i see what you mean, wish those storms were in our direction though:(