Astronomy, Photography and Weather

General Category => Weather & Atmospherics => Topic started by: martinastro on August 26, 2008, 03:04:26 pm

Title: A Call To Dave Grennan (Supercell Related)
Post by: martinastro on August 26, 2008, 03:04:26 pm
Hi Dave

I was looking at the fantastic gallery on your website and found this image of a funnel cloud from a Supercell taken from Raheny, Dublin, 18 Aug 2005 during a thunderstorm...,com_zoom/Itemid,27/page,view/catid,1/PageNo,1/key,6/hit,1/

I am very much interested in this subject and was wondering if you had any other info or images from that event?. It has been on my mind to ask you about this for a long time but I kept forgetting, until now. Hope you don't mind the question.

I was lucky enough to see an LP Supercell from Maghera on Aug 1st this year...

Before this, Martin North from Ballymena caught a HP supercell near Belfast on July 30th 2006

I would be fascinated to learn any further info on the Raheny event.

Thanks  :)

Title: Re: A Call To Dave Grennan (Supercell Related)
Post by: davegrennan on August 26, 2008, 10:47:42 pm
Hi Martin,

Unfortunately, I don;t have any other photos.  How it happened is I came home from work one evening and remarked to my wife that it had gotten extremely dark very suddenly.  I looked outside and saw the blackest most evil cloud I had ever seen.  I was just about to run upstairs and grab my camera when I noticed the supercell.  The base of the clouds were 'lumpy' for want of a better word and I clearly saw the rotation beginning, then out popped a funnel with made its way toward the groud.  It never quite reached the ground.  I was stunned.  I watched until I realised that the funnel wasn't going to make it all the way down and then I ran for the Camera.  The resulting photo was the one you see.  By the time I took the shot, thats all that was left of it.  An amazing event to watch.

However it wasn't the closest I'd ever been to a tornado.

New years day 2005.  My mum died the previous week and this was my first time to visit her grave.  Because of the day that was in it, I was able to drive my car to within 30 metres of the grave.  I just got to the graveside looked up and saw an evil looking black wall rushing across the graveyard.  I knew this was not good!  I ran back to my car and just slammed the door when the back of the car was lifted a few inches and just dropped.  Lightning danced all around a visibility was about 5-7 feet.  I saw a man appear out of the darkness standing two feet behind my car and I blew my horn to attract his attention to get into the car.  Even so close he did not hear my horn and disappeared into the darkness. Then suddenly visibility seemed to improve.  I looked left and saw more lightning.  What I saw next stunned me.  I black rotating column about 3 metres wide.  I could clearly see debris rotating about it (outside of the main black column).  I knew instantly it was a tornado.  It was about 150 metres away from mea and at that time was also moving away from me (I didn't see it approach).  Almost as soon as it happened visibility went back to 5-7 feet.  I sat there really scared until about 5 minutes later I saw blue sky appear again.

My Dad lives 5 minutes up the road and when I arrived there I was literally shaking.  News reports later comfirmed a tornado had overturned a car in west Dublin.  I can only assume the one I saw was a second funnel as surely it couldn;t have travelled across the entire city.  It was certainly the scariest weather event I have ever (and probably ever will) witness.

Title: Re: A Call To Dave Grennan (Supercell Related)
Post by: martinastro on August 27, 2008, 01:45:55 pm
Dave, thanks very much for taking the time out to write that fantastic and detailed reply which I appreciate very much. Now I'm delighted I asked!.

That sounds like not only a great example of severe weather in Ireland, but quite a terrifying experience also. Not many people can say they have had a closer encounter with a tornado in this country, that makes two on this forum already, which shows just how often these events occur. Did you get any investigators ringing you after the New Year's day event , such as John Tyrrell from TORRO?. The account you wrote is amazing reading.

The sequence of events at the graveyard matches the classic severe weather structures on a storm cell. The dark wall moving toward you must have been the gust front with shelf cloud marking the leading edge of the storm cell. Behind that is the precip core where lightning would be most frequent, behind that was the rain free base where tornados can lurk. The improved visiblity after the encounter confirms that. (see image below - cell moving L to R)


I may have read on a few news websites about the car incident in Dublin so I must get back on the net and do some more research. The incredible experience you kindly shared with me has just got me even more interested in this subject than ever before!

Thanks also for the supercell and funnel info from the first account. I could imagine the adrenalin pumping as you ran for the camera!. Must have been quite a vortex whipped up by the rotation in the cell.

Thanks again Dave for the information, I will be returning to this thread again and again.  :)

Title: Re: A Call To Dave Grennan (Supercell Related)
Post by: Roman White on September 13, 2008, 11:46:54 am
Martin, what a nice picture! How simply it describes the structure of a storm cell!  :)